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_______________general description the max6301?ax6304* low-power microprocessor (?) supervisory circuits provide maximum adjustability for reset and watchdog functions. the reset threshold can be adjusted to any voltage above 1.22v, using external resistors. in addition, the reset and watchdog timeout periods are adjustable using external capaci- tors. a watchdog select pin extends the watchdog time- out period to 500x. the reset function features immunity to power-supply transients. these four devices differ only in the structure of their reset outputs (see the selector guide ). the max6301?ax6304 are available in the space-saving 8-pin ?ax package, as well as 8-pin pdip and so packages. applications medical equipment embedded controllers intelligent instruments critical ? monitoring portable equipment set-top boxes battery-powered computers computers/controllers ____________________________features adjustable reset threshold adjustable reset timeout adjustable watchdog timeout 500x watchdog timeout multiplier 4? supply current reset or reset output options push-pull or open-drain output options guaranteed reset asserted at or above v cc = 1v (max6301/max6303) power-supply transient immunity watchdog function can be disabled pdip/so/?ax packages available max6301?ax6304 +5v, low-power ? supervisory circuits with adjustable reset/watchdog ________________________________________________________________ maxim integrated products 1 0.1 f max6301 max6302 max6303 max6304 v cc reset in v in c swt c srt srt gnd swt wdi wds reset p i/o reset (reset) r2 r1 r l r l max6301 only max6302 only 8 7 6 5 1 2 3 4 wds = 0 for normal mode wds = 1 for extended mode ( ) are for max6302/max6304. pin configuration 1 2 8 7 v cc reset (reset) wdi wds reset in gnd srt swt max6301 max6302 max6303 max6304 dip/so/ max top view 3 4 6 5 ( ) are for max6302/max6304. typical operating circuit 19-1078; rev 4; 9/10 ordering information ordering information continued at end of data sheet. for pricing, delivery, and ordering information, please contact maxim direct at 1-888-629-4642, or visit maxim? website at www.maxim-ic.com. selector guide feature max6301 max6302 max6303 max6304 acti ve-low reset acti ve-h i g h reset op en- d rai n reset outp ut ? p ush- p ul l reset outp ut ? p i n- p ackag e 8- pd ip /s o/ ? ax 8- pd ip /s o/ ? ax 8- pd ip /s o/ ? ax 8- pd ip /s o/ ? ax ?ax is a registered trademark of maxim integrated products, inc. part temp range pin-package max6301 cpa 0? to +70? 8 pdip max6301csa 0? to +70? 8 so max6301cua 0? to +70? 8 ?ax max6301epa -40? to +85? 8 pdip max6301esa -40? to +85? 8 so devices are available in both leaded and lead(pb)-free/rohs- compliant packaging. specify lead-free by adding the ? symbol at the end of the part number when ordering.
max6301?ax6304 +5v, low-power ? supervisory circuits with adjustable reset/watchdog 2 _______________________________________________________________________________________ absolute maximum ratings electrical characteristics (v cc = +2v to +5.5v, t a = t min to t max , unless otherwise noted. typical values are at v cc = +5v and t a = +25?.) 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 .................................................................................... -0.3v to +7.0v reset in, swt, srt ..................................-0.3v to (v cc + 0.3v) wdi, wds..............................................................-0.3v to +7.0v reset, reset max6301 .......................................................-0.3v to +7.0v max6302/max6303/max6304...............-0.3v to (v cc + 0.3v) input current v cc ...............................................................................?0ma gnd..............................................................................?0ma output current reset, reset ..............................................................?0ma continuous power dissipation (t a = +70?) pdip (derate 9.09mw/? above +70?) ......................727mw so (derate 5.88mw/? above +70?) .........................471mw ?ax (derate 4.10mw/? above +70?) ....................330mw operating temperature range max630_c_a ......................................................0? to +70? max630_e_a ...................................................-40? to +85? storage temperature range .............................-65? to +160? lead temperature (soldering, 10s) .................................+300? soldering temperature (reflow) lead(pb)-free...............................................................+260? containing lead (pb)...................................................+240? parameter symbol conditions min typ max units max6301c/max6303c 1.00 5.50 max6301e/max6303e 1.20 5.50 operating voltage range (note 1) v cc max6302/max6304 1.31 5.50 v supply current (note 2) i cc no load 4.0 7.0 ? reset timer v reset in falling, v cc = 5.0v 1.195 1.220 1.245 reset input threshold voltage v th v reset in rising, v cc = 5.0v 1.240 1.265 v reset input hysteresis v hyst 20 mv reset input leakage current i reset in ?.01 ? na v cc 4.5v, i source = 0.8ma v cc - 0.4 v cc = 2v, i source = 0.4ma v cc - 0.4 reset output-voltage high (max6302/max6303/max6304) v oh max6302/max6304, v cc = 1.31v, r l = 10k ? v cc - 0.3 v v cc 4.5v, i sink = 3.2ma 0.4 v cc = 2v, i sink = 1.6ma 0.4 v cc = 1v, i sink = 50?, t a = 0? to +70? 0.3 reset output-voltage low (max6301/max6303/max6304 v ol max6301/ max6303 v cc = 1.2v, i sink = 100?, t a = -40? to +85? 0.3 v v cc to reset delay t rd v cc = falling at 1mv/? 63 ? reset input pulse width t ri comparator overdrive = 50mv 26 ? reset timeout period (note 3) t rp c srt = 1500pf 2.8 4.0 5.2 ms max6301, v reset = v cc ? reset output leakage current max6302, v reset = v gnd ? ?
max6301?ax6304 +5v, low-power ? supervisory circuits with adjustable reset/watchdog _______________________________________________________________________________________ 3 10,000 0 0.001 0.01 0.1 1 10 100 1000 reset timeout period vs. c srt 1 max6301-4 toc01 c srt (nf) reset timeout period (ms) 10 100 1000 v cc = 5v 10,000 0 0.001 0.01 0.1 1 10 100 1000 extended-mode watchdog timeout period vs. c swt (wds = v cc ) 1 max6301-4 toc02 c swt (nf) watchdog timeout period (s) 10 100 1000 v cc = 5v 10,000 0.1 0.001 0.01 0.1 1 10 100 1000 normal-mode watchdog timeout period vs. c swt (wds = gnd) 1 max6301-4 toc03 c swt (nf) watchdog timeout period (ms) 10 100 1000 v cc = 5v electrical characteristics (continued) (v cc = +2v to +5.5v, t a = t min to t max , unless otherwise noted. typical values are at v cc = +5v and t a = +25?.) note 1: reset is guaranteed valid from the selected reset threshold voltage down to the minimum v cc . note 2: wds = v cc , wdi unconnected. note 3: precision timing currents of 500na are present at both the srt and swt pins. timing capacitors connected to these nodes must have low leakage consistent with these currents to prevent timing errors. note 4: the sink/source is supplied through a resistor, and is proportional to v cc (figure 8). at v cc = 2v, it is typically ?4?. __________________________________________typical operating characteristics (c swt = c srt = 1500pf, t a = +25?, unless otherwise noted.) parameter symbol conditions min typ max units watchdog timer v ih 0.7 x v cc wdi, wds input threshold v il 0.3 x v cc v v cc = 4.5v to 5.5v 30 wdi pulse width t wp v cc = 2v to 4.5v 60 ns wdi, wds leakage current extended mode disabled ? ? wdi sink/source current (note 4) extended mode enabled ?0 ? wds = gnd, c swt = 1500pf 2.8 4.0 5.2 ms watchdog timeout period (note 3) t wd wds = v cc , c swt = 1500pf 1.4 2.0 2.6 s
max6301?ax6304 +5v, low-power ? supervisory circuits with adjustable reset/watchdog 4 _______________________________________________________________________________________ ____________________________typical operating characteristics (continued) (c swt = c srt = 1500pf, t a = +25?, unless otherwise noted.) 4.25 2.50 -40 40 supply current vs. temperature 3.25 3.00 2.75 4.00 max6301-4 toc07 temperature ( c) supply current ( a) 080 -60 -20 60 20 100 3.75 3.50 4.50 5.00 4.75 v cc = 5.0v v cc = 2.0v reset deasserted no load 1.220 -40 40 reset in threshold voltage vs. temperature 1.218 max6301-4 toc08 temperature ( c) reset reference voltage (v) 080 -60 -20 60 20 100 1.216 1.214 1.222 1.226 1.224 -40 40 v cc to reset delay vs. temperature (v cc falling) 68 max6301-4 toc09 temperature ( c) propagation delay ( s) 080 -60 -20 60 20 100 64 60 56 52 72 76 v cc falling at 1mv/ s reset and watchdog timeout vs. supply voltage 4.12 max6301-4 toc10 v cc (v) t rp /t wp (ms) 23 5 46 4.08 4.04 4.00 3.96 4.16 3.6 2.6 6.0 2.0 4.0 supply current vs. supply voltage 2.8 3.4 max6301-4 toc04 supply voltage (v) supply current ( a) 3.0 5.0 1.5 2.5 4.5 3.5 5.5 3.2 3.0 3.8 4.2 4.0 reset deasserted no load 4.05 3.80 -40 40 reset and normal-mode watchdog timeout period vs. temperature 3.85 4.00 max6301-4 toc05 temperature ( c) t rp /t wd (ms) 080 -60 -20 60 20 100 3.95 3.90 4.10 4.20 4.15 v cc = 5.0v 0 0 200 400 600 1000 800 40 max6301-4 toc06 reset threshold overdrive (mv) transient duration ( s) 80 120 30 70 110 20 60 100 10 50 90 reset occurs above the curve see the negative-going v cc transients section v rst = 4.60v maximum transient duration vs. reset threshold overdrive (v rst )
max6301?ax6304 +5v, low-power ? supervisory circuits with adjustable reset/watchdog _______________________________________________________________________________________ 5 pin description pin name function 1 reset in reset input. high-impedance input to the reset comparator. connect this pin to the center point of an external resistor voltage-divider network to set the reset threshold voltage. the reset threshold voltage is calculated as follows: v rst = 1.22 x (r1 + r2)/r2 (see the typical operating circuit ). 2 gnd ground 3 srt set reset-timeout input. connect a capacitor between this input and ground to select the reset timeout period (t rp ). determine the period as follows: t rp = 2.67 x c srt , with c srt in pf and t rp in ? (see the typical operating circuit ). 4swt set watchdog-timeout input. connect a capacitor between this input and ground to select the basic watchdog timeout period (t wd ). determine the period as follows: t wd = 2.67 x c swt , with c swt in pf and t wd in ?. the watchdog function can be disabled by connecting this pin to ground. 5 wds watchdog-select input. this input selects the watchdog mode. connect to ground to select normal mode and the basic watchdog timeout period. connect to v cc to select extended mode, multiplying the basic timeout period by a factor of 500. a change in the state of this pin resets the watchdog timer to zero. 6 wdi watchdog input. a rising or falling transition must occur on this input within the selected watchdog timeout period, or a reset pulse will occur. the capacitor value selected for swt and the state of wds determine the watchdog timeout period. the watchdog timer clears and restarts when a transition occurs on wdi or wds. the watchdog timer is cleared when reset is asserted and restarted after reset deasserts. in the extended watchdog mode (wds = v cc ), the watchdog function can be disabled by driving wdi with a three-stated driver or by leaving wdi unconnected. open-drain, active-low reset output (max6301) reset (max6301/ max6303) push-pull, active-low reset output (max6303) reset changes from high to low whenever the monitored voltage (v in ) drops below the selected reset threshold (v rst ). reset remains low as long as v in is below v rst . once v in exceeds v rst , reset remains low for the reset timeout period and then goes high. the watchdog timer triggers a reset pulse (t rp ) whenever the watchdog timeout period (t wd ) is exceeded. open-drain, active-high reset output (max6302) 7 reset (max6302/ max6304 push-pull, active-high reset output (max6304) reset changes from low to high whenever the monitored voltage (v in ) drops below the selected reset threshold (v rst ). reset remains high as long as v in is below v rst . once v in exceeds v rst , reset remains high for the reset timeout period and then goes low. the watchdog timer triggers a reset pulse (t rp ) whenever the watchdog timeout period (t wd ) is exceeded. 8v cc supply voltage. bypass to ground with a 0.1? capacitor placed as close as possible to the pin.
detailed description reset function/output the reset output is typically connected to the reset input of a ?. a ?? reset input starts or restarts the ? in a known state. the max6301?ax6304 ? supervisory circuits provide the reset logic to prevent code-execution errors during power-up, power-down, and brownout conditions (see the typical operating circuit ). for the max6301/max6303, reset changes from high to low whenever the monitored voltage (v in ) drops below the reset threshold voltage (v rst ). reset remains low as long as v in is below v rst . once v in exceeds v rst , reset remains low for the reset timeout period, then goes high. when a reset is asserted due to a watchdog timeout condition, reset stays low for the reset timeout period. any time reset asserts, the watch- dog timer clears. at the end of the reset timeout period, reset goes high and the watchdog timer is restarted from zero. if the watchdog timeout period is exceeded again, then reset goes low again. this cycle contin- ues unless wdi receives a transition. on power-up, once v cc reaches 1v, reset is guaran- teed to be a logic-low. for information about applica- tions where v cc is less than 1v, see the ensuring a valid reset /reset output down to v cc = 0v (max6303/ max6304) section. as v cc rises, reset remains low. when v in rises above v rst , the reset timer starts and reset remains low. when the reset timeout period ends, reset goes high. on power-down, once v in goes below v rst , reset goes low and is guaranteed to be low until v cc drops below 1v. for information about applications where v cc is less than 1v, see the ensuring a valid reset /reset output down to v cc = 0v (max6303/ max6304) section. the max6302/max6304 active-high reset output is the inverse of the max6301/max6303 active-low reset output, and is guaranteed valid for v cc > 1.31v. reset threshold these supervisors monitor the voltage on reset in. the max6301?ax6304 have an adjustable reset threshold voltage (v rst ) set with an external resistor voltage-divider (figure 1). use the following formula to calculate v rst (the point at which the monitored voltage triggers a reset): where v rst is the desired reset threshold voltage and v th is the reset input threshold (1.22v). resistors r1 and r2 can have very high values to minimize current consumption. set r2 to some conveniently high value (1m ? , for example) and calculate r1 based on the desired reset threshold voltage, using the following formula: watchdog timer the watchdog circuit monitors the ?? activity. if the ? does not toggle the watchdog input (wdi) within t wd (user selected), reset asserts. the internal watchdog timer is cleared by reset, by a transition at wdi (which can detect pulses as short as 30ns), or by a transition at wds. the watchdog timer remains cleared while reset is asserted; as soon as reset is released, the timer starts counting (figure 2). the max6301?ax6304 feature two modes of watchdog timer operation: normal mode and extended mode. in normal mode (wds = gnd), the watchdog timeout period is determined by the value of the capacitor con- nected between swt and ground (see the selecting the reset and watchdog timeout capacitor section). in extended mode (wds = v cc ), the watchdog timeout period is multiplied by 500. for example, in the extended mode, a 1? capacitor gives a watchdog timeout period of 22 minutes (see the extended-mode watchdog timeout period vs. c swt graph in the typical operating characteristics ). in extended mode, the watchdog function can be disabled by leaving wdi unconnected or by three-stating the driver connected to wdi. in this mode, the watchdog input is internally driven low during the watchdog timeout period, then momentarily pulses high, resetting the r1 r2 v v 1 rst th = ? ? ? ? ? ? ? () ? v vr1r2 r2 v rst th = + () () 0.1f max6301 max6302 max6303 max6304 v cc reset in r2 r1 v in v rst = 1.22 ( r1 + r2 ) r2 max6301?ax6304 +5v, low-power ? supervisory circuits with adjustable reset/watchdog 6 _______________________________________________________________________________________ figure 1. calculating the reset threshold voltage (v rst )
watchdog counter. when wdi is left unconnected, the watchdog timer is cleared by this internal driver just before the timeout period is reached (the internal driver pulls wdi high at about 94% of t wd ). when wdi is three-stated, the maximum allowable leakage current of the device driving wdi is 10?. in normal mode (wds = gnd), the watchdog timer cannot be disabled by three-stating wdi. wdi is a high-impedance input in this mode. do not leave wdi unconnected in normal mode. applications information selecting the reset and watchdog timeout capacitor the reset timeout period is adjustable to accommodate a variety of ? applications. adjust the reset timeout period (t rp ) by connecting a specific value capacitor (c srt ) between srt and ground (figure 3). calculate the reset timeout capacitor as follows: c srt = t rp /2.67 max6301?ax6304 +5v, low-power ? supervisory circuits with adjustable reset/watchdog _______________________________________________________________________________________ 7 v cc v cc 0v 0v wdi reset normal mode (wds = gnd) t wd t rp v cc v cc 0v 0v wdi reset extended mode (wds = v cc ) t wd x 500 t rp figure 2a. watchdog timing diagram, wds = gnd figure 2b. watchdog timing diagram, wds = v cc 0.1 f max6301 max6302 max6303 max6304 v cc gnd c srt = t rp 2.67 v cc c swt c srt c srt in pf t rp in s c swt = t wd 2.67 c swt in pf t wd in s srt swt figure 3. calculating the reset (c srt ) and watchdog (c swt ) timeout capacitor values
max6301?ax6304 with c srt in pf and t rp in ?. c srt must be a low-leak- age (< 10na) type capacitor. ceramic is recommended. the watchdog timeout period is adjustable to accom- modate a variety of ? applications. with this feature, the watchdog timeout can be optimized for software execution. the programmer can determine how often the watchdog timer should be serviced. adjust the watchdog timeout period (t wd ) by connecting a specif- ic value capacitor (c swt ) between swt and ground (figure 3). for normal-mode operation, calculate the watchdog timeout capacitor as follows: c swt = t wd /2.67 where c swt is in pf and t wd is in ?. c swt must be a low-leakage (< 10na) type capacitor. ceramic is recommended. monitoring voltages other than v cc the typical operating circuit monitors v cc . voltages other than v cc can easily be monitored, as shown in figure 4. calculate v rst as shown in the reset threshold section. wake-up timer in some applications, it is advantageous to put a ? into sleep mode, periodically wake it up to perform checks and/or tasks, then put it back into sleep mode. the max6301 family of supervisors can easily accom- modate this technique. figure 5 illustrates an example using the max6302 and an 80c51. in figure 5, just before the ? puts itself into sleep mode, it pulls wds high. the ?? i/o pins maintain their logic levels while in sleep mode and wds remains high. this places the max6302 in extended mode, increasing the watchdog timeout 500 times. when the watchdog timeout period ends, a reset is applied on the 80c51, waking it up to perform tasks. while the ? is performing tasks, the 80c51 pulls wds low (select- ing normal mode), and the max6302 monitors the ? for hang-ups. when the ? finishes its tasks, it puts itself back into sleep mode, drives wds high, and starts the cycle over again. this is a power-saving tech- nique, since the ? is operating only part of the time and the max6302 has very low quiescent current. adding a manual reset function a manual reset option can easily be implemented by con- necting a normally open momentary switch in parallel with r2 (figure 6). when the switch is closed, the voltage on reset in goes to zero, initiating a reset. when the switch is released, the reset remains asserted for the reset timeout period and then is cleared. the pushbut- ton switch is effectively debounced by the reset timer. +5v, low-power ? supervisory circuits with adjustable reset/watchdog 8 _______________________________________________________________________________________ 0.1f max6301 max6302 max6303 max6304 v cc reset in r2 r1 v in v rst = 1.22 ( r1 + r2 ) r2 v cc figure 4. monitoring votlages other than v cc max6302 v cc reset wdi wds v cc i/o i/o i/o gnd 80c51 v cc v cc gnd rst *three-state leakage must be < 10 a. * figure 5. wake-up timer 0.1f max6301 max6302 max6303 max6304 v cc reset in r2 r1 v cc figure 6. adding a manual reset function
interfacing to ?s with bidirectional reset pins since reset is open-drain, the max6301 interfaces easily with ?s that have bidirectional reset pins, such as the motorola 68hc11 (figure 7). connecting reset directly to the ?? reset pin with a single pullup allows either device to assert reset. negative-going v cc transients in addition to issuing a reset to the ? during power-up, power-down, and brownout conditions, these supervisors are relatively immune to short-duration negative-going transients (glitches). the maximum transient duration vs. reset threshold overdrive graph in the typical operating characteristics shows this relationship. the area below the curves of the graph is the region in which these devices typically do not generate a reset pulse. this graph was generated using a negative- going pulse applied to v in , starting above the actual reset threshold (v rst ) and ending below it by the mag- nitude indicated (reset-threshold overdrive). as the magnitude of the transient increases (farther below the reset threshold), the maximum allowable pulse width decreases. typically, a v cc transient that goes 100mv below the reset threshold and lasts 50? or less will not cause a reset pulse to be issued. watchdog input current extended mode in extended mode (wds = v cc ), the wdi input is inter- nally driven through a buffer and series resistor from the watchdog counter (figure 8). when wdi is left unconnected, the watchdog timer is serviced within the watchdog timeout period by a very brief low-high-low pulse from the counter chain. for minimum watchdog input current (minimum overall power consumption), leave wdi low for the majority of the watchdog timeout period, pulsing it low-high-low (> 30ns) once within the period to reset the watchdog timer. if instead wdi is externally driven high for the majority of the timeout period, typically 70? can flow into wdi. normal mode in normal mode (wds = gnd), the internal buffer that drives wdi is disabled. in this mode, wdi is a standard cmos input and leakage current is typically 100pa, regardless of whether wdi is high or low. ensuring a valid reset /reset output down to v cc = 0v (max6303/max6304) when v cc falls below 1v, reset /reset current sinking (sourcing) capabilities decline drastically. in the case of the max6303, high-impedance cmos-logic inputs connected to reset can drift to undetermined voltages. this presents no problem in most applica- tions, since most ?s and other circuitry do not operate with v cc below 1v. max6301?ax6304 +5v, low-power ? supervisory circuits with adjustable reset/watchdog _______________________________________________________________________________________ 9 max6301 v cc reset v cc v cc reset gnd p reset to other system components 0.1 f 4.7k ? figure 7. interfacing to ?s with bidirectional reset i/o pins max6301 max6302 max6303 max6304 watchdog timer to reset generator to mode control wdi wds figure 8. watchdog input structure
max6301?ax6304 in those applications where reset must be valid down to 0v, adding a pulldown resistor between reset and ground sinks any stray leakage currents, holding reset low (figure 9). the value of the pulldown resistor is not critical; 100k ? is large enough not to load reset and small enough to pull reset to ground. for applica- tions using the max6304, a 100k ? pullup resistor between reset and v cc will hold reset high when v cc falls below 1v (figure 10). watchdog-software considerations to help the watchdog timer monitor software execution more closely, set and reset the watchdog input at differ- ent points in the program, rather than pulsing the watchdog input high-low-high or low-high-low. this technique avoids a stuck loop in which the watchdog timer would continue to be reset within the loop, keeping the watchdog from timing out. figure 11 shows an example of a flow diagram where the i/o driving the watchdog input is set high at the beginning of the program, set low at the beginning of every subroutine or loop, then set high again when the program returns to the beginning. if the program should hang in any subroutine the problem would quickly be corrected, since the i/o is continually set low and the watchdog timer is allowed to time out, causing a reset or interrupt to be issued. when using extended mode, as described in the watchdog input current section, this scheme does result in higher average wdi input current than does the method of leaving wdi low for the majority of the timeout period and periodically pulsing it low-high-low. layout considerations srt and swt are precision current sources. when developing the layout for the application, be careful to minimize board capacitance and leakage currents around these pins. traces connected to these pins should be kept as short as possible. traces carrying high-speed digital signals and traces with large voltage potentials should be routed as far from these pins as possible. leakage currents and stray capacitance (e.g., a scope probe) at these pins could cause errors in the reset and/or watchdog timeout period. when evaluating these parts, use clean prototype boards to ensure accurate reset and watchdog timeout periods. reset in is a high-impedance input that is typically driven by a high-impedance resistor-divider network (e.g., 1m ? to 10m ? ). minimize coupling to transient sig- nals by keeping the connections to this input short. any dc leakage current at reset in (e.g., a scope probe) causes errors in the programmed reset threshold. note that sensitive pins are located on the gnd side of the device, away from the digital i/o, to simplify board layout. +5v, low-power ? supervisory circuits with adjustable reset/watchdog 10 ______________________________________________________________________________________ max6303 v cc reset v cc gnd 0.1 f 100k ? figure 9. ensuring reset valid to v cc = 0v max6304 v cc reset gnd v cc 100k ? 0.1 f figure 10. ensuring reset valid to v cc = 0v start set wdi low subroutine or program loop set wdi high return end figure 11. watchdog flow diagram
max6301?ax6304 +5v, low-power ? supervisory circuits with adjustable reset/watchdog ______________________________________________________________________________________ 11 ordering information (continued) chip information process: cmos part temp range pin-package max6302 cpa 0? to +70? 8 pdip max6302csa 0? to +70? 8 so max6302cua 0? to +70? 8 ?ax max6302epa -40? to +85? 8 pdip max6302esa -40? to +85? 8 so max6303 cpa 0? to +70? 8 pdip max6303csa 0? to +70? 8 so max6303cua 0? to +70? 8 ?ax max6303epa -40? to +85? 8 pdip max6303esa -40? to +85? 8 so max6304 cpa 0? to +70? 8 pdip MAX6304CSA 0? to +70? 8 so max6304cua 0? to +70? 8 ?ax max6304epa -40? to +85? 8 pdip max6304esa -40? to +85? 8 so devices are available in both leaded and lead(pb)-free/rohs- compliant packaging. specify lead-free by adding the ? symbol at the end of the part number when ordering. package information for the latest package outline information and land patterns, go to www.maxim-ic.com/packages . note that a "+", "#", or "-" in the package code indicates rohs status only. package draw- ings may show a different suffix character, but the drawing per- tains to the package regardless of rohs status. package type package code outline no. land pattern no. 8 pdip p8-1 21-0043 8 so s8-2 21-0041 90-0096 8 ?ax u8-1 21-0036 90-0092
max6301?ax6304 +5v, low-power ? supervisory circuits with adjustable reset/watchdog 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. 12 ____________________maxim integrated products, 120 san gabriel drive, sunnyvale, ca 94086 408-737-7600 2010 maxim integrated products maxim is a registered trademark of maxim integrated products, inc. +5v, low-power ? supervisory circuits with adjustable reset/watchdog revision history revision number revision date description pages changed 0 7/96 initial release 1 12/05 added lead-free notation. 1, 11 2 3/07 updated typical operating circuit .1 3 3/09 updated pin description , applications information , figure 3, and package information . 5, 7, 11 4 9/10 updated absolute maximum ratings , correct part number. 2, 9, 11, 12

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