? semiconductor components industries, llc, 2002 may, 2002 rev. 4 1 publication order number: max811/d max811, max812 4-pin m p reset monitors the max811 and max812 are costeffective system supervisor circuits designed to monitor v cc in digital systems and provide a reset signal to the host processor when necessary. a manual reset input is provided to override the reset monitor, and is suitable for use as a pushbutton reset. no external components are required. the reset output is driven active within 20 m sec (4 m sec for f version) of v cc falling through the reset voltage threshold. reset is maintained active for a minimum of 140 msec after v cc rises above the reset threshold. the max812 has an activehigh reset output while the max811 has an activelow reset output. the output of the max811 is guaranteed valid down to v cc = 1 v. both devices are available in a 4pin sot143 package. the max811/12 are optimized to reject fast transient glitches on the v cc line. low supply current of 7 m a (v cc = 3.3 v) makes these devices suitable for battery powered applications. features ? precision v cc monitor for 1.8 v, 2.7 v, 3.0 v, 3.3 v, 5.0 v nominal supplies ? manual reset input ? 140 msec guaranteed minimum reset , reset output duration ? reset output guaranteed to v cc = 1.0 v (max811) ? low 7 m a supply current ? v cc transient immunity ? small sot1434 package ? no external components typical applications ? computers ? embedded systems ? battery powered equipment ? critical m p power supply monitoring typical operating circuit gnd max811 push v cc reset mr button v cc reset input (active low) gnd processor v cc pin connections 1 gnd 4 v cc 2 max811 (reset ) 3 mr max812 (reset) sot143 case 318a 1 2 3 4 see detailed ordering and shipping information in the package dimensions section on page 6 of this data sheet. ordering information see general marking information in the device marking section on page 6 of this data sheet. device marking information http://onsemi.com
max811, max812 http://onsemi.com 2 maximum ratings* rating symbol value unit supply voltage (v cc to gnd) +6.0 v reset , reset 0.3 to (v cc +0.3) v input current, v cc 20 ma output current, reset , reset 20 ma operating temperature range t a 40 to +85 c storage temperature range t stg 65 to +150 c lead temperature (soldering, 10 sec) +260 c *this is a stress rating only and functional operation of the device at these or any other conditions above those indicated in the operational sections of the specifications is not implied. exposure to absolute maximum rating conditions for extended periods may affect device reliab ility. electrical characteristics (v cc = 5 v for l/m versions, v cc = 3.3 v for t/s versions, v cc = 3 v for r version, v cc = 2.0 v for f version. t a = 40 c to +85 c unless otherwise noted. typical values are at t a = +25 c.) (note 1) characteristics test conditions symbol min typ max unit v cc range v cc 1.2 5.5 v supply current v cc v th , for l, m, r, s, t, f v cc v th , for l, m, r, s, t v cc v th , for f i cc 7.0 10 6.0 15 15 12 m a reset threshold max81_l: t a = +25 c t a = 40 c to +85 c max81_m: t a = +25 c t a = 40 c to +85 c max81_t: t a = +25 c t a = 40 c to +85 c max81_s: t a = +25 c t a = 40 c to +85 c max81_r: t a = +25 c t a = 40 c to +85 c max81_f: t a = +25 c t a = 40 c to +85 c v th 4.54 4.50 4.30 4.25 3.03 3.00 2.88 2.85 2.58 2.55 1.71 1.70 4.63 4.38 3.08 2.93 2.63 1.75 4.72 4.75 4.46 4.50 3.14 3.15 2.98 3.00 2.68 2.70 1.79 1.80 v reset threshold tempco 30 ppm/ c v cc to reset delay v cc = v th to v th 125 mv; l, m, r, s, t, f 20 5.0 m sec reset active timeout period v cc = v th(max) t rp 140 280 560 msec mr minimum pulse width tmr 10 m sec mr glitch immunity 0.1 m sec mr to reset propagation delay t md 0.5 m sec mr input threshold v cc v th(max) , max81_l/m v ih v il 2.3 0.8 v v cc v th(max) , max81_r/s/t/f v ih v il 0.7 v cc 0.15 v cc v mr pullup resistance 10 20 40 k w reset output voltage high (max812) i source = 150 m a; v cc v th(min) v oh 0.8 v cc v 1. production testing done at t a = +25 c, over temperature limits guaranteed by design.
max811, max812 http://onsemi.com 3 electrical characteristics (continued) (v cc = 5 v for l/m versions, v cc = 3.3 v for t/s versions, v cc = 3 v for r version, v cc = 2.0 v for f version. t a = 40 c to +85 c unless otherwise noted. typical values are at t a = +25 c.) (note 1) characteristics symbol test conditions min typ max unit reset output voltage low (max812) v ol max812f only, i sink = 500 m a, v cc = v th(max) max812r/s/t only, i sink = 1.2 ma, v cc = v th(max) max812l/m only, i sink = 3.2 ma, v cc = v th(max) 0.2 0.3 0.4 v reset output voltage low (max811) v ol max811r/s/t only, i sink = 1.2 ma, v cc = v th(min) max811f only, i sink = 500 m a, v cc = v th(min) max811l/m only, i sink = 3.2 ma, v cc = v th(min) i sink = 50 m a, v cc 1.0 v 0.3 0.4 tbd v reset output voltage high (max811) v oh max811l/m only, i source = 800 m a, v cc v th(max) max811r/s/t/f only, i source = 500 m a, v cc v th(max) v cc 1.5 0.8 v cc v 1. production testing done at t a = +25 c, over temperature limits guaranteed by design. 2. reset output for max811, reset output for max812. pin description pin number symbol description 1 gnd ground 2 reset (max811) reset output remains low while v cc is below the reset voltage threshold, and for at least 140 msec min. after v cc rises above reset threshold. 2 reset (max812) reset output remains high while v cc is below the reset voltage threshold, and for at least 140 msec min. after v cc rises above reset threshold. 3 mr manual reset input generates a reset when mr is below v il . 4 v cc supply voltage
max811, max812 http://onsemi.com 4 applications information v cc transient rejection the max811/12 provides accurate v cc monitoring and reset timing during powerup, powerdown, and brownout/sag conditions, and rejects negativegoing transients (glitches) on the power supply line. figure 1 shows the maximum transient duration vs. maximum negative excursion (overdrive) for glitch rejection. any combination of duration and overdrive that lays under the curve will not generate a reset signal. combinations above the curve are detected as a brownout or powerdown. transient immunity can be improved by adding a capacitor in close proximity to the v cc pin of the max811/12. figure 1. maximum transient duration vs. overdrive for glitch rejection at 25 c maximum transient duration ( sec) reset comparator overdrive, [v cctp v cc ](mv) 400 320 240 160 80 0 t a = +25 c 1 5 100 1000 max811/12 duration v cc v th overdrive reset signal integrity during powerdown the max811 reset output is valid to v cc = 1.0 v. below this voltage the output becomes an aopen circuit'' and does not sink current. this means cmos logic inputs to the m p will be floating at an undetermined voltage. most digital systems are completely shutdown well above this voltage. however, in situations where reset must be maintained valid to v cc = 0 v, a pulldown resistor must be connected from reset to ground to discharge stray capacitances and hold the output low (figure 2). this resistor value, though not critical, should be chosen such that it does not appreciably load reset under normal operation (100 k w will be suitable for most applications). similarly, a pullup resistor to v cc is required for the max812 to ensure a valid high reset for v cc below 1.1 v. figure 2. ensuring reset valid to v cc = 0 v v cc gnd v cc max811 reset r1 100 k processors with bidirectional i/o pins some m p's (such as motorola's 68hc11) have bidirectional reset pins. depending on the current drive capability of the processor pin, an indeterminate logic level may result if there is a logic conflict. this can be avoided by adding a 4.7 k w resistor in series with the output of the max811/12 (figure 3). if there are other components in the system which require a reset signal, they should be buf fered so as not to load the reset line. if the other components are required to follow the reset i/o of the m p, the buffer should be connected as shown with the solid line. figure 3. interfacing to bidirectional reset i/o gnd max811 v cc reset v cc reset gnd v cc buffer 4.7 k p buffered reset to other system components
max811, max812 http://onsemi.com 5 typical characteristics powerdown reset delay ( ) 14 12 10 8 6 4 2 0 40 20 0 20 40 60 85 8 6 4 2 0 40 20 0 20 40 60 85 40 20 0 20 40 60 85 40 20 0 20 40 60 85 40 20 0 20 40 60 85 40 15 10 35 60 65 50 40 30 20 10 0 50 40 30 20 10 0 245 240 235 230 225 250 temperature ( c) temperature ( c) temperature ( c) temperature ( c) temperature ( c) temperature ( c) supply current ( powerup reset timeout (msec) normalized threshold (v) a) supply current ( a) 1.003 1.002 1.001 1.000 0.999 0.998 0.997 0.996 0.994 0.995 max81xl/m max81xr/s/t/f v od = 20 mv v od = 100 mv v od = 200 mv v od = 200 mv v od = 100 mv v od = 20 mv v od = 200 mv v od = 100 mv v od = 20 mv l/m r/s/t v cc = 3 v v cc = 5 v v cc = 1 v v cc = 5 v v cc = 3 v v cc = 1 v sec powerdown reset delay ( ) sec figure 4. supply current vs. temperature (no load, max81xr/s/t/f) figure 5. supply current vs. temperature (no load, max81xl/m) figure 6. powerdown reset delay vs. temperature (max81xf) figure 7. powerdown reset delay vs. temperature (max81xl/m/r/s/t) figure 8. powerup reset timeout vs. temperature figure 9. normalized reset threshold vs. temperature
max811, max812 http://onsemi.com 6 and = part number code and temperature range (twodigit code) = year and quarter code = lot id number marking diagram 12 3 4 12 3 4 ordering information device threshold voltage marking and 12 package (qty/reel) max811leust* 4.63 s1 max811meust* 4.38 s2 max811teust 3.08 s3 max811seust* 2.93 s4 max811reust* 2.63 s5 max811feust 1.75 s7 3000 units tape and reel max812leust* 4.63 t1 3000 units tape and reel max812meust* 4.38 t2 max812teust 3.08 t3 max812seust* 2.93 t4 max812reust* 2.63 t5 max812feust 1.75 t7 *default: contact your on semiconductor sales representative for other threshold voltage options.
max811, max812 http://onsemi.com 7 package dimensions sot143 case 318a05 issue r dim a min max min max inches 2.80 3.04 0.110 0.120 millimeters b 1.20 1.39 0.047 0.055 c 0.84 1.14 0.033 0.045 d 0.39 0.50 0.015 0.020 f 0.79 0.93 0.031 0.037 g 1.78 2.03 0.070 0.080 h 0.013 0.10 0.0005 0.004 j 0.08 0.15 0.003 0.006 k 0.46 0.60 0.018 0.024 l 0.445 0.60 0.0175 0.024 r 0.72 0.83 0.028 0.033 s 2.11 2.48 0.083 0.098 notes: 1. dimensioning and tolerancing per ansi y14.5m, 1982. 2. controlling dimension: millimeter. g s r c j a l f d b 1 34 2 h k
max811, max812 http://onsemi.com 8 on semiconductor and are registered trademarks of semiconductor components industries, llc (scillc). scillc reserves the right to mak e changes without further notice to any products herein. scillc makes no warranty, representation or guarantee regarding the suitability of its products for any particular purpose, nor does scillc assume any liability arising out of the application or use of any product or circuit, and s pecifically disclaims any and all liability, including without limitation special, consequential or incidental damages. atypicalo parameters which may be provided in scillc data sheets and/or specifications can and do vary in different applications and actual performance may vary over time. all operating parameters, including atypicalso must be validated for each customer application by customer's technical experts. scillc does not convey any license under its patent rights nor the rights of others. scillc products are not designed, intended, or authorized for use as components in systems intended for surgical implant into the body , or other applications intended to support or sustain life, or for any other application in which the failure of the scillc product could create a sit uation where personal injury or death may occur. should buyer purchase or use scillc products for any such unintended or unauthorized application, buyer shall indem nify and hold scillc and its of ficers, employees, subsidiaries, affiliates, and distributors harmless against all claims, costs, damages, and expenses, and re asonable attorney fees arising out of, directly or indirectly, any claim of personal injury or death associated with such unintended or unauthorized u se, even if such claim alleges that scillc was negligent regarding the design or manufacture of the part. scillc is an equal opportunity/affirmative action employ er. publication ordering information japan : on semiconductor, japan customer focus center 4321 nishigotanda, shinagawaku, tokyo, japan 1410031 phone : 81357402700 email : r14525@onsemi.com on semiconductor website : http://onsemi.com for additional information, please contact your local sales representative. max811/d literature fulfillment : literature distribution center for on semiconductor p.o. box 5163, denver, colorado 80217 usa phone : 3036752175 or 8003443860 toll free usa/canada fax : 3036752176 or 8003443867 toll free usa/canada email : onlit@hibbertco.com n. american technical support : 8002829855 toll free usa/canada
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