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general description the max6678 monitors its own temperature and the temperatures of two external diode-connected transis- tors, which typically reside on the die of a cpu or otherintegrated circuit. the device reports temperature values in digital form using a 2-wire serial interface. the max6678 provides a programmable alarm output to gen- erate interrupts, throttle signals, or overtemperature shut- down signals. the 2-wire serial interface accepts standard system management bus (smbus) write byte, read byte, send byte, and receive byte commands to read the tempera-ture data and program the alarm thresholds. the tem- perature data controls a pwm output signal to adjust the speed of a cooling fan, thereby minimizing noise when the system is running cool, but providing maxi- mum cooling when power dissipation increases. five gpio pins provide additional flexibility. the gpio power-up states are set by connecting the gpio preset inputs to ground or v cc . the max6678 is available in a 20-pin qsop packageand a 5mm x 5mm thin qfn package. it operates from 3.0v to 5.5v and consumes just 500? of supply current. applications desktop computersnotebook computers workstations servers networking equipment features ? two thermal-diode inputs ? local temperature sensor ? five gpio input/outputs ? two pwm outputs for fan drive (open drain; maybe pulled up to +5v) ? programmable fan-control characteristics ? automatic fan spin-up ensures fan start ? controlled rate of change ensures unobtrusivefan-speed adjustments ? 1 c remote temperature accuracy (+60 c to +145 c) ? temperature monitoring begins at por for fail-safe system protection ? ot output for throttling or shutdown ? four versions available, each with a differentaddress ? 5mm x 5mm tqfn package max6678 2-channel temperature monitor with dual automatic pwm fan-speed controller and five gpios ________________________________________________________________ maxim integrated products 1 20 19 18 17 preset3pwmout2 v cc pwmout1 16 gpio0 1312 11 14 15 gpio3 gpio2 gpio1 ot preset0 4 3 2 1 preset4 gpio4 smbclk smbdata 5 dxp1 6789 dxn dxp2 gnd preset2 10 preset1 max6678 *connect exposed paddle to gnd top view 5mm x 5mm thin qfn pin configurations ordering information 19-3306; rev 0; 5/04 for pricing, delivery, and ordering information, please contact maxim/dallas direct! at 1-888-629-4642, or visit maxim? website at www.maxim-ic.com. * ep = exposed paddle. part temp range pin-package smbus address MAX6678AEP90 -40? to +125? 20 qsop 1001000 max6678aep92 -40? to +125? 20 qsop 1001001 max6678aep94 -40? to +125? 20 qsop 1001010 max6678aep96 -40? to +125? 20 qsop 1001011 max6678atp90 -40? to +125? 20 thinqfn-ep* 1001000 max6678atp92 -40? to +125? 20 thinqfn-ep* 1001001 max6678atp94 -40? to +125? 20 thinqfn-ep* 1001010 max6678atp96 -40? to +125? 20 thinqfn-ep* 1001011 smbus is a trademark of intel corp. pin configurations continued at end of data sheet. typical operating circuit appears at end of data sheet. downloaded from: http:///
max6678 2-channel temperature monitor with dual automatic pwm fan-speed controller and five gpios 2 _______________________________________________________________________________________ absolute maximum ratings electrical characteristics(v cc = +3.0v to +5.5v, t a = -40? to +125?, unless otherwise noted. typical values are at v cc = +3.3v, t a = +25?.) stresses beyond those listed under ?bsolute maximum ratings?may cause permanent damage to the device. these are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. exposure to absolute maximum rating conditions for extended periods may affect device reliability. v cc to gnd ..............................................................-0.3v to +6v ot , smbdata, smbclk, pwmout_, gpio_ to gnd ......................................................-0.3v to +6v dxp_ to gnd ..........................................-0.3v to + (v cc + 0.3v) dxn to gnd ..........................................................-0.3v to +0.8v preset_ to gnd ....................................-0.3v to + (v cc + 0.3v) smbdata, ot , pwmout_ current....................-1ma to +50ma dxn current .......................................................................?ma esd protection (all pins, human body model) ..................2000v continuous power dissipation (t a = +70?) 20-pin qsop (derate 9.1mw/? above +70?).......... 727mw 20-pin tqfn (derate 34.5mw/? above +70?) .......2759mw operating temperature range .........................-40? to +125? junction temperature ......................................................+150? storage temperature range ............................-65? to +150? lead temperature (soldering, 10s) .................................+300? parameter symbol conditions min typ max units operating supply voltage range v cc +3.0 +5.5 v operating current i s interface inactive, adc active 0.5 1 ma +25? t r +125?, t a = 60? ? v cc = 3.3v 0? t r +145?, +25? t a +100? ? external temperature error,v cc = 3.3v 0? t r +145?, 0? t a +125? ? ? +25? t r +100? ?.5 internal temperature error v cc = +3.3v 0? t a +125? 4 ? 1 c temperature resolution 8 bits conversion time 200 250 300 ms pwm frequency tolerance (note 1) -20 +20 % high level 80 100 120 remote-diode sourcing current low level 8 10 12 ? dxn source voltage 0.7 v digital inputs and outputs output low voltage (sink current)( ot , gpio_, smbdata, pwmout_) v ol i out = 6ma 0.4 v output high leakage current( ot , gpio_, smbdata, pwmout_) i oh 1 a v cc = 3v to 3.6v 0.8 logic-low input voltage (smbdata,smbclk, preset_, gpio_) v il v cc = 3.6v to 5.5v 0.8 v v cc = 3v to 3.6v 2.1 logic-high input voltage (smbdata,smbclk, preset_, gpio_) v ih v cc = 3.6v to 5.5v 2.1 v input leakage current 1 a input capacitance c in 5p f smbus timing serial clock frequency f sclk 100 khz downloaded from: http:///
max6678 2-channel temperature monitor with dual automatic pwm fan-speed controller and five gpios _______________________________________________________________________________________ 3 electrical characteristics (continued)(v cc = +3.0v to +5.5v, t a = -40? to +125?, unless otherwise noted. typical values are at v cc = +3.3v, t a = +25?.) parameter symbol conditions min typ max units clock low period t low 10% to 10% 4 s clock high period t high 90% to 90% 4.7 ? bus free time between stop andstart conditions t buf 4.7 ? smbus start condition setup time t su:sta 90% of smbclk to 90% of smbdata 4.7 ? start condition hold time t hd:sto 10% of smbdata to 10% of smbclk 4 s stop condition setup time t su:sto 90% of smbclk to 10% of smbdata 4 s data setup time t su:dat 10% of smbdata to 10% of smbclk 250 ns data hold time t hd:dat 10% of smbclk to 10% of smbdata 300 ns smbus fall time t f 300 ns smbus rise time t r 1000 ns smbus timeout t timeout 29 37 55 ms startup time after por t por 500 ms note 1: deviation from programmed value in table 6. t ypical operating characteristics (t a = +25?, unless otherwise noted.) 400 440 520480 560 600 3.0 4.0 3.5 4.5 5.0 5.5 operating supply current vs. supply voltage max6678 toc02 supply voltage (v) supply current ( a) -4 -2-3 0 -1 1 2 05 0 75 25 100 125 150 remote temperature error vs. remote-diode temperature max6678 toc03 temperature ( c) temperature error ( c) fa irchild 2n3906 downloaded from: http:///
max6678 2-channel temperature monitor with dual automatic pwm fan-speed controller and five gpios 4 _______________________________________________________________________________________ t ypical operating characteristics (continued) (t a = +25?, unless otherwise noted.) -3 -1-2 10 2 3 05 0 25 75 100 125 local temperature error vs. die temperature max6678 toc04 temperature ( c) temperature error ( c) -1.5 0 -0.5-1.0 1.00.5 1.5 2.0 0.01 1 0.1 10 100 1000 remote temperature error vs. power-supply noise frequency max6678 toc05 frequency (khz) temperature error ( c) v in = 250mv p-p square wave applied to v cc with no bypass capacitor -2.5 -1.0-1.5 -2.0 0 -0.5 0.5 1.0 0.01 1 0.1 10 100 1000 local temperature error vs. power-supply noise frequency max6678 toc06 frequency (khz) temperature error ( c) v in = 250mv p-p square wave applied to v cc with no bypass capacitor 0 1.41.2 1.0 0.8 0.6 0.4 0.2 1.81.6 2.0 0.01 1 0.1 10 100 1000 remote temperature error vs. common-mode noise frequency max6678 toc07 frequency (khz) temperature error ( c) v in = ac-coupled to dxp and dxn v in = 100mv p-p square wave 0 0.70.6 0.5 0.4 0.3 0.2 0.1 0.90.8 1.0 0.01 1 0.1 10 100 1000 remote temperature error vs. differential noise frequency max6678 toc08 frequency (khz) temperature error ( c) v in = ac-coupled to dxp v in = 100mv p-p square wave -6 -3-5 -4 -1-2 10 2 0.1 1 10 100 temperature error vs. dxp-dxn capacitance max6678 toc09 dxp-dxn capacitance (nf) temperature error ( c) t a = +25 c 30 31 3332 34 35 -40 10 35 -15 60 110 85 pwmout frequency vs. die temperature max6678 toc10 temperature ( c) pwmout frequency (hz) 30 31 3332 34 35 3.0 4.0 3.5 4.5 5.0 5.5 pwmout frequency vs. supply voltage max6678 toc11 supply voltage (v) pwmout frequency (hz) 0 100 300200 400 500 01 0 1 5 52 0 2 5303540 gpio output voltage vs. gpio sink current max6678 toc12 gpio sink current (ma) gpio output voltage (mv) downloaded from: http:///
detailed description the max6678 temperature sensor and fan controlleraccurately measures the temperature of either two remote pn junctions or one remote pn junction and its own die. the device reports temperature values in digi- tal form using a 2-wire serial interface. the remote pn junction is typically the emitter-base junction of a com- mon-collector pnp on a cpu, fpga, or asic. the max6678 operates from supply voltages of 3.0v to 5.5v and consumes 500? (typ) of supply current. the temperature data controls a pwm output signal to adjust the speed of a cooling fan. the device also fea- tures an overtemperature alarm output to generate interrupts, throttle signals, or shutdown signals. five gpio input/outputs provide additional flexibility. the gpio power-up states are set by connecting the gpio preset inputs to ground or v cc . max6678 2-channel temperature monitor with dual automatic pwm fan-speed controller and five gpios _______________________________________________________________________________________ 5 pin description pin thin qfn qsop name description 13 smbdata smbus serial-data input/output, open drain. can be pulled up to 5.5v,regardless of v cc . open circuit when v cc = 0. 24 smbclk smbus serial-clock input. can be pulled up to 5.5v, regardless of v cc . open circuit when v cc = 0. 3, 12, 13, 14, 16 5, 14, 15, 16, 18 gpio0?pio4 active-low, open-drain gpio pins. can be pulled up to 5.5v, regardless ofv cc . open circuit when v cc = 0. 4, 9, 10, 11, 20 2, 6, 11, 12, 13 preset0?reset4 gpio preset inputs. connect to gnd or v cc to set por value of gpio0?pio4. 5, 7 7, 9 dxp1, dxp2 combined current source and a/d positive input for remote diode. connect toanode of remote-diode-connected temperature-sensing transistor. do not leave floating; connect to dxn if no remote diode is used. place a 2200pf capacitor between dxp_ and dxn for noise filtering. 68 d x n combined remote-diode cathode input. connect cathode of the remote-diode-connected transistor to dxn. 81 0 gnd ground. connect to a clean ground reference. 15 17 ot active-low, open-drain over-temperature output. typically used for systemshutdown or clock throttling. can be pulled up to 5.5v regardless of v cc . open circuit when v cc = 0. 17, 19 1, 19 pwmout1, pwmout2 open-drain output to power transistor driving fan. connect to the gate of a mosfet or base of a transistor. pwmout_ requires a pullup resistor. the pullup resistor can be connected to a supply voltage as high as 5.5v, regardless of the max6678? supply voltage. 18 20 v cc power-supply input. 3.3v nominal. bypass v cc to gnd with 0.1? capacitor. temperature processing block pwm generator block smbus interface and registers logic max6678 gnd v cc smbclk smbdata dxn dxp1 dxp2 pwmout1pwmout2 ot gpio0 gpio4 preset0 preset4 block diagram downloaded from: http:///
max6678 smbus digital interface from a software perspective, the max6678 appears as aset of byte-wide registers. this device uses a standard smbus 2-wire/i 2 c-compatible serial interface to access the internal registers. the max6678 has four differentslave addresses available; therefore, a maximum of four max6678 devices can share the same bus. the max6678 employs four standard smbus protocols: write byte, read byte, send byte, and receive byte (figures 1, 2, and 3). the shorter receive byte protocol allows quicker transfers, provided that the correct data register was previously selected by a read byte instruc- tion. use caution with the shorter protocols in multimaster systems, since a second master could overwrite the command byte without informing the first master. temperature data can be read from registers 00h and 01h. the temperature data format for these registers is 8 bits, with the lsb representing 1? (table 1) and the msb representing +128?. the msb is transmitted first. all values below 0? clip to 00h. table 2 details the register address and function, whetherthey can be read or written to, and the power-on reset (por) state. see tables 2? for all other register functions and the register descriptions section. temperature reading the max6678 contains two external temperature mea-surement inputs to measure the die temperature of cpus or other ics having on-chip temperature-sensing diodes, or discrete diode-connected transistors as shown in the typical operating circuits . for best accuracy, the dis- crete diode-connected transistor should be a small-signaldevice with its collector and base connected together. the on-chip adc converts the sensed temperature and outputs the temperature data in the format shown in table 1. temperature channel 2 can be used to measure either a remote thermal diode or the internal temperature of the max6678. bit d1 of register 02h (table 2) selects local or remote sensing for temperature channel 2 (1 = local). the temperature measurement resolution is 1? for both local and remote temperatures. the temperature accuracy is within ?? for remote temperature measurements from +60? to +100?. 2-channel temperature monitor with dual automatic pwm fan-speed controller and five gpios 6 _______________________________________________________________________________________ write byte format read byte format send byte format receive byte format slave address: equiva-lent to chip-select line of a 3-wire interface command byte: selects whichregister you are writing to data byte: data goes into the registerset by the command byte (to set thresholds, configuration masks, and sampling rate) slave address: equivalentto chip-select line command byte: selectswhich register you are reading from slave address: repeateddue to change in data- flow direction data byte: reads fromthe register set by the command byte command byte: sends com-mand with no data, usually used for one-shot command data byte: reads data fromthe register commanded by the last read byte or write byte transmission; also used for smbus alert response return address s = start condition shaded = slave transmission p = stop condition /// = not acknowledged figure 1. smbus protocols s address rd ack data /// p 7 bits 8 bits wr s ack command ack p 8 bits address 7 bits p 1 ack data 8 bits ack command 8 bits ack wr address 7 bits s s address wr ack command ack s address 7 bits 8 bits 7 bits rd ack data 8 bits /// p downloaded from: http:///
the dxn input is biased at 0.60v above ground by aninternal diode to set up the analog-to-digital inputs for a differential measurement. the worst case dxp-dxn dif- ferential input voltage range is from 0.25v to 0.95v. excess resistance in series with the remote diode causes about +0.5? error per ohm. likewise, a 200? offset voltage forced on dxp-dxn causes about 1? error. high-frequency emi is best filtered at dxp and dxn with an external 2200pf capacitor. this value can be increased to about 3300pf (max), including cable capac- itance. capacitance higher than 3300pf introduces errors due to the rise time of the switched current source. max6678 2-channel temperature monitor with dual automatic pwm fan-speed controller and five gpios _______________________________________________________________________________________ 7 smbclk a = start conditionb = msb of address clocked into slave c = lsb of address clocked into slave d = r/w bit clocked into slave ab cd e fg hi j smbdata t su:sta t hd:sta t low t high t su:dat t su:sto t buf lm k e = slave pulls smbdata line lowf = acknowledge bit clocked into master g = msb of data clocked into slave h = lsb of data clocked into slave i = master pulls data line lowj = acknowledge clocked into slave k = acknowledge clock pulse l = stop condition m = new start condition figure 2. smbus write timing diagram smbclk ab cd e fg h i j k smbdata t su:sta t hd:sta t low t high t su:dat t hd:dat t su:sto t buf a = start conditionb = msb of address clocked into slave c = lsb of address clocked into slave d = r/w bit clocked into slave e = slave pulls smbdata line low l m f = acknowledge bit clocked into masterg = msb of data clocked into master h = lsb of data clocked into master i = master pulls data line low j = acknowledge clocked into slavek = acknowledge clock pulse l = stop condition m = new start condition figure 3. smbus read timing diagram table 1. temperature data byte format temp (?) rounded temp (?) digital output 241 +241 1111 0001 240 +240 1111 0000 126 +126 0111 1110 25 +25 0001 1001 0.50 +1 0000 0001 0.00 0 0000 0000 diode fault (open) 1110 1111 diode fault (short) 1111 1111 downloaded from: http:///
max6678 pwm output 1) the pwmout_ signals are normally used in one of three ways to control the fan? speed: pwmout_ dri-ves the gate of a mosfet or the base of a bipolar transistor in series with the fan? power supply. the typical application circuit shows the pwmout_ dri- ving an n-channel mosfet. in this case, the pwminvert bit (d4 in register 02h) is set to 1. figure 4 shows pwmout_ driving a p-channel mosfet andthe pwm invert bit must be set to zero. 2) pwmout_ is converted (using an external circuit)into a dc voltage that is proportional to duty cycle. this duty-cycle-controlled voltage becomes the power supply for the fan. this approach is less effi- cient than 1), but can result in quieter fan operation. figure 5 shows an example of a circuit that converts the pwm signal to a dc voltage. because this circuit produces a full-scale output voltage when pwmout = 0v, bit d4 in register 02h should be set to zero. 3) pwmout_ directly drives the logic-level pwmspeed-control input on a fan that has this type of input. this approach requires fewer external compo- nents and combines the efficiency of 1) with the low noise of 2). an example of pwmout_ driving a fan with a speed-control input is shown in figure 6. bit d4 in register 02h should be set to 1 when this con- figuration is used. whenever the fan has to start turning from a motionlessstate, pwmout_ is forced high for 2s. after this spin-up period, the pwmout_ duty cycle settles to the prede- termined value. whenever spin-up is disabled (bit 2 in the configuration byte = 1) and the fan is off, the duty cycle changes immediately from zero to the nominal value, ignoring the duty-cycle rate-of-change setting. the frequency-select register controls the frequency of the pwm signal. when the pwm signal modulates the power supply of the fan, a low pwm frequency (usually 33hz) should be used to ensure the circuitry of the brushless dc motor has enough time to operate. when driving a fan with a pwm-to-dc circuit as in figure 5, the highest available frequency (35khz) should be used to minimize the size of the filter capacitors. when using a fan with a pwm control input, the frequency normally should be high as well, although some fans have pwm inputs that accept low-frequency drive. 2-channel temperature monitor with dual automatic pwm fan-speed controller and five gpios 8 _______________________________________________________________________________________ v cc pwmout 10k ? 5v p figure 4. driving a p-channel mosfet for top-side pwm fandrive +3.3v pwmout 18k ? 27k ? 10k ? 120k ? +3.3v +12v 500k ? v out to fan 1 f 1 f 0.01 f 0.1 f figure 5. driving a fan with a pwm-to-dc circuit v cc pwmout 4.7k ? 5v figure 6. controlling a pwm input fan with the max6678?pwm output (typically, the 35khz pwm frequency is used) downloaded from: http:///
the duty cycle of the pwm can be controlled in two ways: 1) manual pwm control by setting the duty cycle of the fan directly through the fan target duty-cycle regis-ters (0bh and 0ch). 2) automatic pwm control by setting the duty cyclebased on temperature. manual pwm duty-cycle control clearing the bits that select the temperature channels forfan control (d5 and d4 for pwmout1 and d3 and d2 for pwmout2) in the fan-configuration register (11h) enables manual fan control. in this mode, the duty cycle written to the fan target duty-cycle register directly con- trols the corresponding fan. the value is clipped to a maximum of 240. any value entered above that is changed to 240 automatically. in this control mode, the value in the maximum duty-cycle register is ignored and does not affect the duty cycle used to control the fan. automatic pwm duty-cycle control in the automatic control mode, the duty cycle is con-trolled by the local or remote temperature according to the settings in the control registers. below the fan-start temperature, the duty cycle is either 0% or is equal to the fan-start duty cycle, depending on the value of bit d3 in the configuration byte register. above the fan- start temperature, the duty cycle increases by one duty cycle step each time the temperature increases by one temperature step. the target duty cycle is calculated based on the following formula; for temperature > fanstarttemperature: where: dc = dutycycle fsdc = fanstartdutycycle t = temperature fst = fanstarttemperature dcss = dutycyclestepsize ts = tempstep duty cycle is recalculated after each temperature con- version if temperature is increasing. if the temperature begins to decrease, the duty cycle is not recalculated until the temperature drops by 5? from the last peak temperature. the duty cycle remains the same until the temperature drops 5? from the last peak temperature or the temperature rises above the last peak temperature. for example, if the temperature goes up to +85? and starts decreasing, duty cycle is not recalculated until thetemperature reaches +80? or the temperature rises above +85?. if the temperature decreases further, the duty cycle is not updated until it reaches +75?. for temperature < fanstarttemperature and d2 of configuration register = 0: dutycycle = 0 for temperature < fanstarttemperature and d2 of configuration register = 1: dutycycle = fanstartdutycycle once the temperature crosses the fan-start tempera-ture threshold, the temperature has to drop below the fan-start temperature threshold minus the hysteresis before the duty cycle returns to either 0% or the fan- start duty cycle. the value of the hysteresis is set by d7 of the fan-configuration register. the duty cycle is limited to the value in the fan maximum duty-cycle register. if the duty-cycle value is larger than the maximum fan duty cycle, it is set to the maximum fan-duty cycle as in the fan maximum duty-cycle register. the temperature step is bit d6 of the fan-configuration register (0dh). notice if temperature crosses fanstarttemperature going up with an initial dutycycle of zero, a spin-up of 2s applies before the duty-cycle calculation controls the value of the fan? duty cycle. fanstarttemperature for a particular channel follows the channel, not the fan. when a fan switches channels, the start temperature also changes to that of the new channel. if dutycycle is an odd number, it is automatically rounded down to the closest even number. dc fsdc t fst dcss ts =+ ( ) - max6678 2-channel temperature monitor with dual automatic pwm fan-speed controller and five gpios _______________________________________________________________________________________ 9 f an-start duty cycle temperature duty cycle register 02h, bit d3 = 1 duty-cycle step size f an-start temperature temp step register 02h,bit d3 = 0 figure 7. automatic pwm duty control downloaded from: http:///
max6678 duty-cycle rate-of-change control to reduce the audibility of changes in fan speed, therate of change of the duty cycle is limited by the values set in the duty-cycle rate-of-change register. whenever the target duty cycle is different from the instantaneous duty cycle, the duty cycle increases or decreases at the rate determined by the duty-cycle rate-of-change byte until it reaches the target duty cycle. by setting the rate of change to the appropriate value, the thermal requirements of the system can be balanced against good acoustic performance. slower rates of change are less noticeable to the user, while faster rates of change can help minimize temperature variations. remember that the fan controller is part of a complex control sys- tem. because several of the parameters are generally not known, some experimentation may be necessary to arrive at the best settings. power-up defaults at power-up, or when the por bit in the configurationbyte register is set, the max6678 has the default set- tings indicated in table 2. some of these settings are summarized below: temperature conversions are active. channel 1 and channel 2 are set to report the remotetemperature channel measurements. channel 1 ot limit = +110 c. channel 2 ot limit = +80 c. manual fan mode. fan duty cycle = 0. pwm invert bit = 0. pwmout_ are high. when using an nmos or npn transistor, the fan startsat full speed on power-up. ot output when temperature exceeds the ot temperature thresh- old and ot is not masked, the ot status register indi- cates a fault and ot output becomes active. if ot for the respective channel is masked off, the ot status register continues to be set, but the ot output does not become active.the fault flag and the output can be cleared only by reading the ot status register and the temperature reg- ister of that channel. if the ot status bit is cleared, ot reasserts on the next conversion if the temperature stillexceeds the ot temperature threshold. gpio inputs/outputs and presets the max6678 contains five gpio pins (gpio0 throughgpio4). when set as an output, the gpio pin connects to the drains of internal n-channel mosfets. when the n-channel mosfet is off, the pullup resistor (see the typical operating circuit ) provides a logic-level high output. when a gpio pin is configured as an input, readthe state of gpio_ from the gpio value register (15h). the max6678 powers up with gpio0, gpio1, and gpio2 high impedance and gpio3 and gpio4 pulled low. after 2ms, the gpios go to their assigned preset values. the preset values are set by connecting the associated preset inputs to either gnd or v cc . with preset??connected to gnd, gpio??pulls low; withpreset??connected to v cc , gpio??pulls high through the pullup resistor. after power-up, the functionsand states of the gpios can be read and controlled using registers 15h and 16h. register descriptions the max6678 contains 26 internal registers. these reg-isters store temperature, allow control of the pwm out- puts, determine if the max6678 is measuring from the internal or remote temperature sensors, and set the gpio as inputs or outputs. temperature registers (00h and 01h) these registers contain the results of temperature mea-surements. the value of the msb is +128?, and the value of the lsb is +1?. temperature data for remote diode 1 is in the temperature channel 1 register. temperature data for remote diode 2 or the local sen- sor (selectable by bit d1 in the configuration byte) is stored in the temperature channel 2 register. configuration byte (02h) the configuration byte register controls timeout condi-tions and various pwmout signals. the por state of the configuration byte register is 00h. see table 3 for configuration byte definitions. channel 1 and channel 2 ot limits (03h and 04h) set channel 1 (03h) and channel 2 (04h) temperaturethresholds with these two registers. once the tempera- ture is above the threshold, the ot output is asserted low (for the temperature channels that are not masked). thepor state of the channel 1 ot limit register is 6eh, and the por state of the channel 2 ot limit register is 50h. 2-channel temperature monitor with dual automatic pwm fan-speed controller and five gpios 10 ______________________________________________________________________________________ downloaded from: http:///
max6678 2-channel temperature monitor with dual automatic pwm fan-speed controller and five gpios ______________________________________________________________________________________ 11 table 2. register map read/ write register no. /address por state function d7 d6 d5 d4 d3 d2 d1 d0 r 00h 0000 0000 temperature channel 1 msb (+128 c) lsb (+1?) r 01h 0000 0000 temperature channel 2 msb (+128 c) lsb (+1?) r/w 02h 0001 1000 configuration byte reserved; set to 0 res er ved ; s et t o 0 timeout: 0 = enabled, 1 = disabled pwmout 1 pwm invert pwmout 2 pwm invert min duty cycle: 0 = 0%, 1 = fan - start duty cycle temp channel 2 source: 1= local, 0 = remote 2 spin-up disable r/w 03h 0110 1110 temperature channel 1 ot limit msb lsb (+1?) r/w 04h 0101 0000 temperature channel 2 ot limit msb lsb (+1?) r 05h 00xx xxxx ot status channel 1: 1 = fault channel 2: 1 = fault r/w 06h 00xx xxxx ot mask channel 1: 1 = masked channel 2: 1 = masked r/w 07h 0110 000x (96 = 40%) pwmout1 start duty cycle msb (128/240) lsb (2/240) r/w 08h 0110 000x (96 = 40%) pwmout2 start duty cycle msb (128/240) lsb (2/240) r/w 09h 1111 000x (240 = 100%) pwmout1 max duty cycle msb (128/240) lsb (2/240) r/w 0ah 1111 000x (240 = 100%) pwmout2 max duty cycle msb (128/240) lsb (2/240) r/w 0bh 0000 000x pwmout1 target duty cycle msb (128/240) lsb (2/240) r/w 0ch 0000 000x pwmout2 target duty cycle msb (128/240) lsb (2/240) r 0dh 0000 000x pwmout1 instantaneous duty cycle msb (128/240) lsb (2/240) *** gpio0 through gpio4 por values set by preset0 through preset4. downloaded from: http:///
max6678 o o t t status (05h) read the ot status register to determine which channel recorded an overtemperature condition. bit d7 is high ifthe fault reading occurred from channel 1. bit d6 is high if the fault reading occurred in channel 2. the ot status register is cleared only by reading its contents.after reading the ot status register, a temperature reg- ister read must be done. reading the contents of theregister also makes the ot output high impedance. if the fault is still present on the next temperature mea- surement cycle, the corresponding bits and the ot out- put are set again. the por state of the ot status regis- ter is 00h. o o t t mask (06h) set bit d7 to 1 in the ot mask register to prevent the ot output from asserting on faults in channel 1. set bit d6 to 1 to prevent the ot output from asserting on faults in channel 2. the por state of the ot mask reg- ister is 00h. 2-channel temperature monitor with dual automatic pwm fan-speed controller and five gpios 12 ______________________________________________________________________________________ table 2. register map (continued) read/ write register no. /address por state function d7 d6 d5 d4 d3 d2 d1 d0 r 0eh 0000 000x pwmout2 instantaneous duty cycle msb (128/240) lsb (2/240) r/w 0fh 0000 0000 temperature channel 1 fan- start temperature msb l s b r/w 10h 0000 0000 temperature channel 2 fan- start temperature msb l s b r/w 11h 0000 000x fan configuration hys ter esi s: 0 = 5c, 1 = 10c temp step: 0 = 1?, 1 = 2? pwmout 1 control: 1 = channel1 pwmout 1 control: 1 = channel 2 pwmout 2 control: 1 = channel 1 pwmout 2 control: 1 = channel 2 r/w 12h 1011 01xx duty-cycle rate of change pwmout 1 msb pwmout 1 lsb pwmout 2 msb pwmout 2 lsb r/w 13h 0101 0101 duty-cycle step size pwmout 1 msb pwmout 1 lsb pwmout 2 msb pwmout 2 lsb r/w 14h 010x xxxx pwm frequency select select a select b select c r/w 15h xxx0 0000 gpio function gpio4: 0 = output, 1 = input gpio3: 0 = output,1 = input gpio2: 0 = output, 1 = input gpio1: 0 = output,1 = input gpio0: 0 = output,1 = input r/w 16h xxx*** gpio value gpio4 gpio3 gpio2 gpio1 gpio0 r fdh 0000 0001 read device revision 0000 0001 r feh 1000 0110 read device id 1 0 0 0 0 1 1 0 r ffh 0100 1101 read manufacturer id 0100 1101 *** gpio0 through gpio4 por values set by preset0 through preset4. downloaded from: http:///
pwmout start duty cycle (07h and 08h) the pwmout start duty-cycle register determines thepwm duty cycle where the fan starts spinning. bit d2 in the configuration byte register (min duty cycle) determines the starting duty cycle. if the min duty cycle bit is 1, the duty cycle is the value written to the fan-start duty-cycle register at all temperatures below the fan-start temperature. if the min duty cycle bit is zero, the duty cycle is zero below the fan-start tempera- ture and has this value when the fan-start temperature is reached. a value of 240 represents 100% duty cycle. writing any value greater than 240 causes the fan speed to be set to 100%. the por state of the fan-start duty-cycle register is 96h, 40%. pwmout max duty cycle (09h and 0ah) the pwmout maximum duty-cycle register sets themaximum allowable pwmout duty cycle between 2/240 (0.83% duty cycle) and 240/240 (100% duty cycle). any values greater than 240 are recognized as 100% maximum duty cycle. the por state of the pwmout maximum duty-cycle register is f0h, 100%. in manual control mode, this register is ignored. pwmout target duty cycle (0bh and 0ch) in automatic fan-control mode, this register contains thepresent value of the target pwm duty cycle, as deter- mined by the measured temperature and the duty- cycle step size. the actual duty cycle requires time before it equals the target duty cycle if the duty-cycle rate-of-change register is set to a value other than zero. in manual fan-control mode, write the desired value of the pwm duty cycle directly into this register. the por state of the fan-target duty-cycle register is 00h. pwmout1 instantaneous duty cycle, pwmout2 instantaneous duty cycle (0dh, 0eh) these registers always contain the duty cycle of thepwm signals presented at the pwm output. the por state of the pwmout instantaneous duty- cycle register is 00h. channel 1 and channel 2 fan-start temperature (0fh and 10h) these registers contain the temperatures at which fancontrol begins (in automatic mode). see the automatic pwm duty-cycle control section for details on setting the fan-start thresholds. the por state of the channel 1and channel 2 fan-start temperature registers is 00h. max6678 2-channel temperature monitor with dual automatic pwm fan-speed controller and five gpios ______________________________________________________________________________________ 13 table 3. configuration byte definition (02h) bit name por state function 7 reserved; set to 0 6 reserved; set to 0 5 timeout 0 set timeout to zero to enable smbus timeout for prevention of bus lockup. setto 1 to disable this function. 4 fan1 pwm invert 0 set fan pwm invert to zero to force pwmout1 low when the duty cycle is100%. set to 1 to force pwmout1 high when the duty cycle is 100%. 3 fan2 pwm invert 0 set fan pwm invert to zero to force pwmout2 low when the duty cycle is100%. set to 1 to force pwmout2 high when the duty cycle is 100%. 2 min duty cycle 0 set min duty cycle to zero for a 0% duty cycle when the measuredtemperature is below the fan-temperature threshold in automatic mode. when the temperature equals the fan-temperature threshold, the duty cycle is the value in the fan-start duty-cycle register, and it increases with increasing temperature. set min duty cycle to 1 to force the pwm duty cycle to the value in the fan- start duty-cycle register when the measured temperature is below the fan- temperature threshold. as the temperature increases above the temperature threshold, the duty cycle increases as programmed. 1 temperature source select 0 selects either local or remote 2 as the source for temperature channel 2 registerdata. when d1 = 0, the max6678 measures remote 2 and when d1 = 1, the max6678 measures the internal die temperature. 0 spin-up disable 0 set spin-up disable to 1 to disable spin-up. set to zero for normal fan spin-up. downloaded from: http:///
max6678 fan configuration (11h) the fan-configuration register controls the hysteresislevel, temperature step size, and whether the remote or local diode controls the pwmout2 signal (see table 2). set bit d7 of the fan-configuration register to zero toset the hysteresis value to 5?. set bit d7 to 1 to set the hysteresis value to 10?. set bit d6 to zero to set the fan-control temperature step size to 1?. set bit d6 to 1 to set the fan-control temperature step size to +2?. bits d5 to d2 select which pwmout_ channel 1 or channel 2 controls (see table 2). if both are selected for a given pwmout_, the highest pwm value is used. if neither is selected, the fan is controlled by the value written to the fan-target duty-cycle register. also in this mode, the value written to the target duty-cycle register is not limited by the value in the maximum duty-cycle register. it is, however, clipped to 240 if a value above 240 is written. the por state of the fan-configuration register is 00h. duty-cycle rate of change (12h) bits d7, d6, and d5 (channel 1) and d4, d3, and d2(channel 2) of the duty-cycle rate-of-change register set the time between increments of the duty cycle. each increment is 2/240 of the duty cycle (see table 4). this allows the time from 33% to 100% duty cycle to be adjust- ed from 5s to 320s. the rate-of-change control is always active in manual mode. to make instant changes, set bits d7, d6, and d5 (channel 1) or d4, d3, and d2 (channel 2) = 000. the por state of the duty-cycle rate-of-change register is b4h (1s between increments). duty-cycle step size (13h) bits d7?4 (channel 1) and bits d3?0 (channel 2) of theduty-cycle step-size register change the size of the duty- cycle change for each temperature step. the por state of the duty-cycle step size register is 55h (see table 5). pwm frequency select (14h) set bits d7, d6, and d5 (select a, b, and c) in the pwmfrequency-select register to control the pwmout frequen- cy (see table 6). the por state of the pwm frequency- select register is 40h, 33hz. the lower frequencies are usually used when driving the fan? power-supply pin as in the typical application circuit , with 33hz being the most common choice. the 35khz frequency setting isused for controlling fans that have logic-level pwm input pins for speed control. the minimum duty-cycle resolution is decreased from 2/240 to 4/240 at the 35khz frequen- cy setting. for example, a result that would return a value of 6/240 is truncated to 4/240. 2-channel temperature monitor with dual automatic pwm fan-speed controller and five gpios 14 ______________________________________________________________________________________ table 4. setting the time between duty-cycle increments d7:d5, d4:d2 time between increments (s) time from 33% to 100% (s) 000 0 0 001 0.0625 5 010 0.125 10 011 0.25 20 100 0.5 40 101 1 80 110 2 160 111 4 320 table 5. setting the duty-cycle change d7:d4, d3:d0 change in duty cycle per temperature step temperature range for fan control (1 c step, 33% to 100%) 0000 0 0 0001 2/240 80 0010 4/240 40 0011 6/240 27 0100 8/240 20 0101 10/240 16 ... 1000 16 10 ... ... ... 1111 31 5 table 6. pwm frequency select pwm frequency (hz) select a select b select c 20 000 33 010 50 100 100 1 1 0 35k x x 1 note: at 35khz, duty-cycle resolution is decreased from a res- olution of 2/240 to 4/240. downloaded from: http:///
gpio function register (15h) the gpio function register (15h) sets the gpio_ states.write a zero to set a gpio as an output. write a one to set a gpio as an input. gpio value register (16h) the gpio value register (16h) contains the state ofeach gpio input when a gpio is configured as an input. when configured as an output, write a one or zero to set the value of the gpio output. applications information remote-diode considerations temperature accuracy depends upon having a good-quality, diode-connected, small-signal transistor. accuracy has been experimentally verified for all the devices listed in table 7. the max6678 can also direct- ly measure the die temperature of cpus and other icswith on-board temperature-sensing diodes. the transistor must be a small-signal type with a rela- tively high forward voltage. this ensures that the input voltage is within the a/d input voltage range. the for- ward voltage must be greater than 0.25v at 10? at the highest expected temperature. the forward voltage must be less than 0.95v at 100? at the lowest expect- ed temperature. the base resistance has to be less than 100 ? . tight specification of forward-current gain (+50 to +150, for example) indicates that the manufac-turer has good process control and that the devices have consistent characteristics. effect of ideality factor the accuracy of the remote-temperature measurementsdepends on the ideality factor (n) of the remote ?iode (actually a transistor). the max6678 is optimized for n = 1.008, which is the typical value for the intel pentium?iii and the amd athlon mp model 6. if a sense transistor with a different ideality factor is used, the output data is different. fortunately, the difference is predictable. assume a remote-diode sensor designed for a nominal ideality factor n nominal is used to measure the tem- perature of a diode with a different ideality factor, n 1 . the measured temperature t m can be corrected using: where temperature is measured in kelvin.as mentioned above, the nominal ideality factor of the max6678 is 1.008. as an example, assume the max6678 is configuredwith a cpu that has an ideality factor of 1.002. if the diode has no series resistance, the measured data is related to the real temperature as follows: for a real temperature of +85? (358.15k), the mea- sured temperature is +82.87? (356.02k), which is an error of -2.13?. effect of series resistance series resistance in a sense diode contributes addition-al errors. for nominal diode currents of 10? and 100?, change in the measured voltage is: since 1? corresponds to 198.6?, series resistance contributes a temperature offset of: assume that the diode being measured has a series resistance of 3 ? . the series resistance contributes an offset of:the effects of the ideality factor and series resistance are additive. if the diode has an ideality factor of 1.002 and series resistance of 3 ? , the total offset can be cal- culated by adding error due to series resistance witherror due to ideality factor: 1.36? - 2.13? = -0.77? for a diode temperature of +85?.in this example, the effect of the series resistance and the ideality factor partially cancel each other. for best accuracy, the discrete transistor should be a small-signal device with its collector connected to gnd and base connected to dxn. table 7 lists examples of discrete transistors that are appropriate for use with the max6678. 30 453 1 36 ? ? = .. c c 90 198 6 0 453 = v v c c ? ? . . ? vr a a ar ms s =? = ? () 100 10 90 tt n n tt actual m nominal mm = ? ? ? ? ? ? = ? ? ? ? ? ? = .. (. ) 1 1 008 1 002 1 00599 tt n n m actual nominal = ? ? ? ? ? ? 1 max6678 2-channel temperature monitor with dual automatic pwm fan-speed controller and five gpios ______________________________________________________________________________________ 15 pentium is a registered trademark of intel corp.athlon is a trademark of amd. downloaded from: http:///
max6678 adc noise filtering the integrating adc has inherently good noise rejec-tion, especially of low-frequency signals such as 60hz/120hz power-supply hum. micropower operation places constraints on high-frequency noise rejection. lay out the pc board carefully with proper external noise filtering for high-accuracy remote measurements in electrically noisy environments. filter high-frequency electromagnetic interference (emi) at dxp and dxn with an external 2200pf capaci- tor connected between the two inputs. this capacitor can be increased to about 3300pf (max), including cable capacitance. a capacitance higher than 3300pf introduces errors due to the rise time of the switched- current source. twisted pairs and shielded cables for remote-sensor distances longer than 8in, or in partic-ularly noisy environments, a twisted pair is recommend- ed. its practical length is 6ft to 12ft (typ) before noise becomes a problem, as tested in a noisy electronics labo- ratory. for longer distances, the best solution is a shield- ed twisted pair like that used for audio microphones. for example, belden 8451 works well for distances up to 100ft in a noisy environment. connect the twisted pair to dxp and dxn and the shield to ground, and leave the shield? remote end unterminated. excess capacitance at dxn or dxp limits practical remote-sensor distances (see the typical operating characteristics ). for very long cable runs, the cable? parasitic capaci-tance often provides noise filtering, so the recommend- ed 2200pf capacitor can often be removed or reduced in value. cable resistance also affects remote-sensor accuracy. a 1 ? series resistance introduces about +1/2? error. pc board layout checklist 1) place the max6678 as close as practical to theremote diode. in a noisy environment, such as a computer motherboard, this distance can be 4in to 8in, or more, as long as the worst noise sources (such as crts, clock generators, memory buses, and isa/pci buses) are avoided. 2) do not route the dxp/dxn lines next to the deflection coils of a crt. also, do not route the traces across afast memory bus, which can easily introduce +30? error, even with good filtering. otherwise, most noise sources are fairly benign. 3) route the dxp and dxn traces parallel and close to each other, away from any high-voltage traces suchas +12vdc. avoid leakage currents from pc board contamination. a 20m ? leakage path from dxp ground causes approximately +1? error. 4) connect guard traces to gnd on either side of the dxp/dxn traces. with guard traces, placing routingnear high-voltage traces is no longer an issue. 5) route as few vias and crossunders as possible tominimize copper/solder thermocouple effects. 6) when introducing a thermocouple, make sure thatboth the dxp and the dxn paths have matching thermocouples. in general, pc board-induced ther- mocouples are not a serious problem. a copper sol- der thermocouple exhibits 3?/?, and it takes approximately 200? of voltage error at dxp/dxn to cause a +1? measurement error, so most parasitic thermocouple errors are swamped out. 7) use wide traces. narrow traces are more inductive and tend to pick up radiated noise. the 10-mil widthsand spacings recommended are not absolutely nec- essary (as they offer only a minor improvement in leakage and noise), but use them where practical. 8) placing an electrically clean copper ground planebetween the dxp/dxn traces and traces carrying high-frequency noise signals helps reduce emi. 2-channel temperature monitor with dual automatic pwm fan-speed controller and five gpios 16 ______________________________________________________________________________________ table 7. remote-sensor transistormanufacturers manufacturer model no. central semiconductor (usa) cmpt3906 rohm semiconductor (usa) sst3906 samsung (korea) kst3906-tf siemens (germany) smbt3906 downloaded from: http:///
max6678 2-channel temperature monitor with dual automatic pwm fan-speed controller and five gpios ______________________________________________________________________________________ 17 2019 18 17 16 15 14 13 12 3 4 5 6 7 8 v cc pwmout1 gpio0ot smbclk smbdata preset3 pwmout2 top view gpio1gpio2 gpio3 preset0 dxn dxp1 preset4 gpio4 1211 9 10 preset1preset2 gnd dxp2 max6678 qsop pin configurations (continued) chip information transistor count: 23,618process: bicmos remote 1 cpu gpu remote 2 to smbus master 3.0v to 5.5v 3.0v to 5.5v 3.0v to 5.5v 3.0v to 5.5v 3.0v to 5.5v 3.0v to 5.5v 5.0v v f an (5v or 12v) 5v v fan (5v or 12v) 3.0v to 5.5v max6678 dxp1dxn dxp2 smbdata smbclk gpio3 gpio4 gpio2 gpio1 gpio0 ot pwmout2 pwmout1 v cc 5 gnd preset_ to clock throttle orsystem shutdown t ypical application circuit downloaded from: http:///
max6678 2-channel temperature monitor with dual automatic pwm fan-speed controller and five gpios 18 ______________________________________________________________________________________ package information (the package drawing(s) in this data sheet may not reflect the most current specifications. for the latest package outline information, go to www.maxim-ic.com/packages .) qsop.eps e 1 1 21-0055 package outline, qsop .150", .025" lead pitch downloaded from: http:///
max6678 2-channel temperature monitor with dual automatic pwm fan-speed controller and five gpios maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a maxim product. no circuit patent licenses are implied. maxim reserves the right to change the circuitry and specifications without notice at any time. maxim integrated products, 120 san gabriel drive, sunnyvale, ca 94086 408-737-7600 ____________________ 19 2004 maxim integrated products printed usa is a registered trademark of maxim integrated products. package information (continued) (the package drawing(s) in this data sheet may not reflect the most current specifications. for the latest package outline information, go to www.maxim-ic.com/packages .) qfn thin.eps d2 (nd-1) x e e d c pin # 1 i.d. (ne-1) x e e/2 e 0.08 c 0.10 c a a1 a3 detail a 0.15 c b 0.15 c a e2/2 e2 0.10 m c a b pin # 1 i.d. b 0.35x45 l d/2 d2/2 l c l c e e l c c l k k l l e 1 2 21-0140 package outline16, 20, 28, 32, 40l, thin qfn, 5x5x0.8mm detail b l l1 e common dimensions 3.35 3.15 t2855-1 3.25 3.35 3.15 3.25 max. 3.20 exposed pad variations 3.00 t2055-2 3.10 d2 nom. min. 3.20 3.00 3.10 min. e2 nom. max. ne nd pkg. codes 1. dimensioning & tolerancing conform to asme y14.5m-1994.2. all dimensions are in millimeters. angles are in degrees. 3. n is the total number of terminals. 4. the terminal #1 identifier and terminal numbering convention shall conform to jesd 95-1 spp-012. details of terminal #1 identifier are optional, but must be located within the zone indicated. the terminal #1 identifier may be either a mold or marked feature. 5. dimension b applies to metallized terminal and is measured between 0.25 mm and 0.30 mm from terminal tip. 6. nd and ne refer to the number of terminals on each d and e side respectively.7. depopulation is possible in a symmetrical fashion. 8. coplanarity applies to the exposed heat sink slug as well as the terminals. 9. drawing conforms to jedec mo220, except exposed pad dimension for t2855-1, t2855-3 and t2855-6. notes: symbol pkg. n l1 e e d b a3 a a1 k 10. warpage shall not exceed 0.10 mm. jedec t1655-1 3.20 3.00 3.10 3.00 3.10 3.20 0.70 0.80 0.75 4.904.90 0.250.25 0 -- 4 whhb 4 16 0.35 0.30 5.105.10 5.00 0.80 bsc. 5.00 0.05 0.20 ref. 0.02 min. max. nom. 16l 5x5 3.10 t3255-2 3.00 3.20 3.00 3.10 3.20 2.70 t2855-2 2.60 2.60 2.80 2.70 2.80 e 2 2 21-0140 package outline16, 20, 28, 32, 40l, thin qfn, 5x5x0.8mm l 0.30 0.50 0.40 -- - -- - whhc 20 5 5 5.00 5.00 0.300.55 0.65 bsc. 0.45 0.25 4.904.90 0.25 0.65 -- 5.105.10 0.35 20l 5x5 0.20 ref. 0.750.02 nom. 0 0.70 min. 0.05 0.80 max. -- - whhd-1 28 7 7 5.00 5.00 0.250.55 0.50 bsc. 0.45 0.25 4.904.90 0.20 0.65 -- 5.105.10 0.30 28l 5x5 0.20 ref. 0.750.02 nom. 0 0.70 min. 0.05 0.80 max. -- - whhd-2 32 8 8 5.00 5.000.40 0.50 bsc. 0.30 0.25 4.904.90 0.50 -- 5.105.10 32l 5x5 0.20 ref. 0.750.02 nom. 0 0.70 min. 0.05 0.80 max. - 4010 10 5.00 5.00 0.200.50 0.40 bsc. 0.40 0.25 4.904.90 0.15 0.60 5.105.10 0.25 40l 5x5 0.20 ref. 0.75 nom. 0 0.70 min. 0.05 0.80 max. 0.20 0.25 0.30 - 0.35 0.45 0.30 0.40 0.50 down bonds allowed no yes 3.10 3.00 3.20 3.10 3.00 3.20 t2055-3 3.10 3.00 3.20 3.10 3.00 3.20 t2055-4 t2855-3 3.15 3.25 3.35 3.15 3.25 3.35 t2855-6 3.15 3.25 3.35 3.15 3.25 3.35 t2855-4 2.60 2.70 2.80 2.60 2.70 2.80 t2855-5 2.60 2.70 2.80 2.60 2.70 2.80 t2855-7 2.60 2.70 2.80 2.60 2.70 2.80 3.20 3.00 3.10 t3255-3 3.20 3.00 3.10 3.20 3.00 3.10 t3255-4 3.20 3.00 3.10 3.40 3.20 3.30 t4055-1 3.20 3.30 3.40 nono no no nono no no yesyes yes yes yes 3.20 3.00 t1655-2 3.10 3.00 3.10 3.20 yes downloaded from: http:///

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