general description the max7384 dual-speed silicon oscillator replaces ceramic resonators, crystals, and crystal-oscillator modules as the primary and secondary clock source for microcontrollers in 3v, 3.3v, and 5v applications. the max7384 features a factory-programmed high-speed oscillator, a 32.768khz oscillator, a clock-selector input, and a ? power-on-reset (por) supervisor. the clock output can be switched at any time between the high- speed clock and the 32.768khz clock for low-power operation. switchover is synchronized internally to pro- vide glitch-free clock switching. unlike typical crystal and ceramic-resonator oscillator circuits, the max7384 is resistant to vibration and emi. the high-output-drive current and absence of high- impedance nodes makes the oscillator less susceptible to dirty or humid operating conditions. with a wide oper- ating temperature range as standard, the max7384 is a good choice for demanding home appliance, industrial, and automotive environments. the max7384 is available with factory-programmed fre- quencies ranging from 10mhz to 16mhz. see table 1 for standard frequencies and contact the factory for custom frequencies. refer to the max7378 data sheet for frequencies less than 10mhz. the max7384 is available in an 8-pin ?ax package. the max7384 standard operating temperature range is -40? to +125?. see the applications information sec- tion for extended operating temperature range. applications white goods automotive consumer products appliances and controls handheld products portable equipment microcontroller systems features ? 2.7v to 5.5v operation ? high-speed oscillator from 10mhz to 16mhz low-speed 32khz oscillator glitch-free clock-speed switching ? integrated por ? ?0ma clock-output drive capability ? 2.5% initial accuracy ? ?0ppm/? frequency drift ? 50% duty cycle ? 5ns output rise and fall time ? low jitter: 80ps p-p at 16mhz ? 4ma operating current at 16mhz ? 13?, 32khz operating current ? -40? to +125? temperature range max7384 silicon oscillator with low-power frequency switching and reset output ________________________________________________________________ maxim integrated products 1 ordering information osc1 osc2 rst c gnd rst/rst clock e.c. v cc 0.1 f v cc 2.7v to 5.5v max7384 v l 0.1 f i/o port speed t ypical application circuit 19-3493; rev 0; 11/04 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. part* temp range pin- package reset output max7384a_ _ _ -40 c to +125 c8 ?ax active high push-pull MAX7384B_ _ _ -40 c to +125 c8 ?ax active low push-pull max7384c_ _ _ -40 c to +125 c8 ?ax open drain * standard version is shown in bold. the first letter after the part number designates the reset output option. insert the letter corresponding to the desired reset threshold level from table 1 in the next position. insert the two-letter code from table 2 in the remaining two positions for the desired frequency range. table 1 and table 2 are located at the end of the data sheet. pin configuration appears at end of data sheet. ?ax is a registered trademark of maxim integrated products, inc.
max7384 silicon oscillator with low-power frequency switching and reset output 2 _______________________________________________________________________________________ absolute maximum ratings stresses beyond those listed under ?bsolute maximum ratings?may cause permanent damage to the device. these are stress rating s only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specificatio ns is not implied. exposure to absolute maximum rating conditions for extended periods may affect device reliability. v cc to gnd ...........................................................-0.3v to +6.0v all other pins to gnd.................................-0.3v to (v cc + 0.3v) clock, rst current .......................................................?0ma input current (speed)......................................................?0ma continuous power dissipation (t a = +70?) 8-pin ?ax (derate 4.5mw/? above +70?) ... 362mw (u8-1) operating temperature range .........................-55? to +135? junction temperature ......................................................+150? storage temperature range .............................-65? to +150? lead temperature (soldering, 10s) .................................+300? electrical characteristics ( typical operating circuit , v cc = 2.7v to 5.5v, v l = v cc , t a = -40? to +125?. typical values are at v cc = 5.0v, t a = +25?, unless otherwise noted.) (note 1) parameter symbol conditions min typ max units operating supply voltage v cc 2.7 5.5 v f clock = 16mhz, t a = -40? to +125?, no load 8.7 f clock = 14.7456mhz, t a = -40? to +125?, no load 8.0 f clock = 12mhz, t a = -40? to +125?, no load 6.5 f clock = 11.0592mhz, t a = -40? to +125?, no load 6.0 f clock = 10mhz, t a = -40? to +125?, no load 5.4 ma operating supply current i cc f clock = 32.768khz, t a = -40? to +125?, no load 13 25 ? logic inputs (speed) input high voltage v ih 0.7 x v cc input low voltage v il 0.3 x v cc v input current i in v cc = speed = 5.5v 2 ? clock output v l = 4.5v, i source = 7.0ma output high voltage v oh v l = 2.7v, i source = 2.0ma v l - 0.4 v v l = 4.5v, i sink = 20ma output low voltage v ol v l = 2.7v, i sink = 10ma 0.4 v v cc = 5v, t a = +25?, deviation from selected frequency -2.5 +2.5 initial fast clock frequency accuracy f clock v cc = 2.7v to 5.5v, t a = +25?, deviation from selected frequency -5 +3.5 % fast clock temperature coefficient t a = -40? to +125? 50 350 ppm/?
max7384 silicon oscillator with low-power frequency switching and reset output _______________________________________________________________________________________ 3 electrical characteristics (continued) ( typical operating circuit , v cc = 2.7v to 5.5v, v l = v cc , t a = -40? to +125?. typical values are at v cc = 5.0v, t a = +25?, unless otherwise noted.) (note 1) parameter symbol conditions min typ max units v cc = 5v, t a = +25? 32.268 32.768 33.268 slow clock frequency f clock v cc = 2.7v to 5.5v, t a = +25? 31.768 32.768 33.768 khz slow clock temperature coefficient t a = -40? to +125? 50 325 ppm/? duty cycle (note 2) 40 50 60 % output jitter observation of 16mhz for 20s using a 12ghz oscilloscope 80 ps p-p output rise time t r 10% to 90% 5 ns output fall time t f 90% to 10% 5 ns t a = +25? -2 +2 power-on-reset threshold v th v cc rising, deviation from nominal threshold t a = -40? to +125? -5 +5 % power-on-reset hysteresis v hyst difference between rising and falling thresholds 1% power-on-reset delay pordly v cc rising from 0 to 5v in 1? at +25 c 122 ? reset output v l = 4.5v, i source = 7.0ma v cc - 0.4 output high voltage (note 3) v oh v l = 2.7v, i source = 2.0ma v cc - 0.4 v v l = 4.5v, i sink = 20ma 0.4 output low voltage v ol v l = 2.7v, i source = 10ma 0.4 v note 1: all parameters tested at t a = +25?. specifications over temperature are guaranteed by design. note 2: guaranteed by design. not production tested. note 3: for push-pull output only.
max7384 silicon oscillator with low-power frequency switching and reset output 4 _______________________________________________________________________________________ t ypical operating characteristics (v cc = v l = 5v, t a = +25?, frequency = 10mhz, unless otherwise noted.) 48.0 48.5 49.5 49.0 50.0 50.5 -55 21 -17 59 97 135 duty cycle vs. temperature max7384 toc01 temperature ( c) duty cycle (%) frequency = 10mhz 45 47 46 49 48 50 51 2.7 3.9 4.3 3.1 3.5 4.7 5.1 5.5 duty cycle vs. supply voltage max7384 toc02 supply voltage (v) duty cycle (%) frequency = 11.0592mhz 2.90 3.00 2.95 3.10 3.05 3.20 3.15 3.25 -55 21 59 -17 97 135 supply current vs. temperature max7384 toc03 temperature ( c) supply current (ma) frequency = 10mhz 1.5 2.0 3.0 2.5 3.5 4.0 2.7 3.5 3.1 3.9 4.3 4.7 5.1 5.5 supply current vs. supply voltage max7384 toc04 supply voltage (v) supply current (ma) frequency = 11.0592mhz -2.0 -1.0 -1.5 0 -0.5 1.5 1.0 0.5 2.0 2.7 3.5 3.1 3.9 4.3 4.7 5.1 5.5 frequency deviation vs. supply voltage max7384 toc05 supply voltage (v) percent (%) frequency = 11.0592mhz -4 -3 -2 -1 0 1 2 3 4 -55 -17 21 59 97 135 frequency deviation vs. temperature max7384 toc06 temperature ( c) percent (%) frequency = 10mhz channel 1 = clock, channel 2 = v cc 10 s/div settling time from start max7384 toc07 ch1 freq 9.992mhz low resolution clock output waveform (c l = 10pf) max7384 toc08 20ns/div clock output waveform (c l = 50pf) max7384 toc09 20ns/div
max7384 silicon oscillator with low-power frequency switching and reset output _______________________________________________________________________________________ 5 clock output waveform (c l = 100pf) max7384 toc10 20ns/div maximum transient duration vs. reset threshold overdrive max7384 toc11 reset threshold overdrive (v) maximum transient duration (s) 0.19 0.14 0.09 100m 10m 1m 0.01 0.1 1 1 0.04 0.24 v reset = 4.32v channel 1 = clock, channel 2 = speed 10 s/div high-speed to low-speed transition max7384 toc12 channel 1 = clock, channel 2 = speed 40ns/div high-speed to low-speed transition max7384 toc13 channel 1 = clock, channel 2 = speed 10 s/div low-speed to high-speed transition max7384 toc14 channel 1 = clock, channel 2 = speed 100ns/div low-speed to high-speed transition max7384 toc15 5 4 3 2 1 10 13 11 12 14 15 16 supply current vs. frequency max7384 toc16 frequency (mhz) supply current (ma) t ypical operating characteristics (continued) (v cc = v l = 5v, t a = +25?, frequency = 10mhz, unless otherwise noted.)
max7384 detailed description the max7384 is a dual-speed clock generator with inte- grated reset for microcontrollers (?s) and uarts in 3v, 3.3v, and 5v applications. the max7384 is a replace- ment for crystal-oscillator modules, crystals, or ceramic resonators and a system reset ic. the high-speed clock frequency and reset threshold voltage are factory trimmed to specific values (see table 1). a variety of popular standard frequencies are available. the low- speed clock frequency is fixed at 32.768khz; see table 2. no external components are required for setting or adjusting the frequency. oscillator the push-pull clock output drives a load to within 400mv of either supply rail. the clock output remains stable over the full operating voltage range and does not generate short output cycles during either power-on or changing of the frequency. a typical oscillating start- up is shown in the typical operating characteristics . clock-speed selection drive speed low to select slow clock speed (nominally 32.768khz) or high to select full clock speed. speed can be connected to v cc or to gnd to select fast or slow clock speed, or connected to a logic output (such as a ? gpio port) used to change clock speed on the fly. if speed is connected to a ? gpio port, connect a pullup or pulldown resistor to set the clock to the preferred speed on power-up. speed input bias current is 2? (max), so a resistor value as high as 500k ? can be used. applications information interfacing to a microcontroller clock input the max7384 clock output is a push-pull, cmos, logic output that directly drives a ? or ? clock input. there are no impedance-matching issues when using the max7384. refer to the microcontroller data sheet for clock input compatibility with external clock signals. the max7384 requires no biasing components or load capacitance. when using the max7384 to retrofit a crystal oscillator, remove all biasing components from the oscillator input. reset output the max7384 is available with three reset output stage options: push-pull active low, push-pull active high, and open-drain active low. rst is asserted when the moni- tored input (v cc ) drops below the internal v th- threshold and remains asserted for 120? after the monitored input exceeds the internal v th+ threshold. the open-drain rst output requires an external pullup resistor. output jitter the max7384? jitter performance is given in the electrical characteristics table as a peak-to-peak value obtained by observing the output of the max7384 for silicon oscillator with low-power frequency switching and reset output 6 _______________________________________________________________________________________ max7384 rst clock 10mhz to 16mhz (hf oscillator) por v cc 2.7v to 5.5v gnd 32khz (lf oscillator) v l mux logic speed figure 1. functional diagram pin description pin name function 1v cc positive supply voltage. bypass v cc to gnd with a 0.1? capacitor. 2v l output supply voltage. bypass v l to gnd with a 0.1? capacitor. v l must be connected to v cc . 3 speed clock-speed select input. drive speed low to select the 32khz fixed frequency. drive speed high to select factory-trimmed frequency. 4 rst reset output. open-drain or push-pull output. see the ordering information. 5 clock push-pull clock output 6 gnd ground 7 e.c. externally connected. connect to vcc. 8 n.c. no connection. not internally connected.
20s with a 12ghz oscilloscope. jitter measurements are approximately proportional to the output period of the device. thus, a 10mhz device has approximately twice the jitter value of a 20mhz device. the jitter per- formance of all clock sources degrades in the pres- ence of mechanical and electrical interference. the max7384 is relatively immune to vibration, shock, and emi influences and thus provides a considerably more robust clock source than crystal or ceramic resonator- based oscillator circuits. initial power-up and operation an internal power-up reset asserts rst until the supply voltage has risen above the power-on-reset threshold (v th+ ). rst holds the microcontroller in a reset condition until 120? after v cc has risen above v th+ . this reset delay ensures that the clock output and the microcontroller? internal clock circuits have stabilized before the system is allowed to start. typical microcontroller reset delay ranges from 1ms to 250ms to allow a slow crystal oscil- lator circuit to start up. the max7384 has a fast startup, eliminating the need for such a long reset delay. extended temperature operation the max7384 was tested to +135 c during product char- acterization and shown to function normally at this tem- perature (see the typical operating characteristics ). however, production test and qualification is only per- formed from -40 c to +125 c at this time. contact the fac- tory if operation outside this range is required. power-supply considerations the max7384 operates with a 2.7v and 5.5v power- supply voltage. v cc provides power to the the internal circuitry and v l supplies power to the clock and reset outputs. good power-supply decoupling is needed to maintain the power-supply rejection performance of the max7384. bypass both v cc and v l to gnd with a 0.1? surface-mount ceramic capacitor. mount the bypassing capacitors as close to the device as possi- ble. use a larger value bypass capacitor if the max7384 is to operate with a large capacitive load. use a bypass capacitor value of at least 1000 times that of the output load capacitance. max7384 silicon oscillator with low-power frequency switching and reset output _______________________________________________________________________________________ 7 part reset output type reset threshold (v) frequency (mhz) max7384cruk open drain 2.89 10 max7384crut open drain 2.89 11.0592 max7384crvb open drain 2.89 12 max7384crvt open drain 2.89 14.7456 max7384crwb open drain 2.89 16 max7384cmuk open drain 4.38 10 max7384cmut open drain 4.38 11.0592 max7384cmvb open drain 4.38 12 max7384cmvt open drain 4.38 14.7456 max7384cmwb open drain 4.38 16 table 3. standard part numbers suffix reset threshold (v) x 2.50 v 2.71 r 2.89 standard value q 3.13 p 3.34 n 3.44 j 3.96 m 4.38 standard value table 1. standard reset threshold levels suffix standard frequency (mhz) uk 10 ut 11.0592 vb 12 vt 14.7456 wb 16 table 2. standard frequencies contact factory for nonstandard reset threshold options. for all other frequency options, contact factory.
max7384 silicon oscillator with low-power frequency switching and reset output 8 _______________________________________________________________________________________ top view gnd clock rst 1 2 8 7 n.c. e.c. v l speed v cc max 3 4 6 5 max7384 pin configuration chip information transistor count: 2937 process: bicmos
max7384 silicon oscillator with low-power frequency switching and reset output maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a maxim product. no circu it 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 _____________________ 9 2004 maxim integrated products printed usa is a registered trademark of maxim integrated products. package information (the package drawing(s) in this data sheet may not reflect the most current specifications. for the latest package outline info rmation, go to www.maxim-ic.com/packages .) 8lumaxd.eps package ? outline, ? 8l ? umax/usop 1 1 21-0036 j rev. document ? control ? no. approval proprietary ? information title: max 0.043 0.006 0.014 0.120 0.120 0.198 0.026 0.007 0.037 0.0207 ? bsc 0.0256 ? bsc a2 a1 c e b a l front ? view side ? view e h 0.60.1 0.60.1 ? 0.500.1 1 top ? view d 8 a2 0.030 bottom ? view 1 6 s b l h e d e c 0 0.010 0.116 0.116 0.188 0.016 0.005 8 4x ? s inches - a1 a min 0.002 0.95 0.75 0.5250 ? bsc 0.25 0.36 2.95 3.05 2.95 3.05 4.78 0.41 0.65 ? bsc 5.03 0.66 6 0 0.13 0.18 max min millimeters - 1.10 0.05 0.15 dim
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