general description the max6803/max6804/max6805 microprocessor (?) supervisory circuits monitor the power supplies in 2.85v to 5.0v ? and digital systems. they increase circuit reliability and reduce cost by eliminating external com- ponents and adjustments. they also feature a debounced manual reset input. these devices perform a single function: they assert a reset signal whenever the v cc supply voltage declines below a preset threshold or whenever manual reset is asserted. reset remains asserted for a preset timeout period after v cc has risen above the reset threshold or after manual reset is deasserted. the only difference among the three devices is their output. the max6804 (push/pull) and max6805 (open-drain) have an active- low reset output, while the max6803 (push/pull) has an active-high reset output. the max6803/max6804 are guaranteed to be in the correct state for v cc down to 0.7v. the max6805 is guaranteed to be in the cor- rect state for v cc down to 1.0v. the reset comparator in these ics is designed to ignore fast transients on v cc . reset thresholds are factory- trimmable between 2.63v and 4.80v, in approximately 100mv increments. these devices are available with a 1ms min, 20ms min, or 100ms min reset timeout period. ideal for space-critical applications, the max6803/ max6804/max6805 come packaged in a 4-pin sot143. for a lower threshold voltage version, see the max6335/max6336/max6337. applications computers controllers intelligent instruments critical ?/? power monitoring portable/battery-powered equipment automotive features ? ultra-low 0.7v operating supply voltage ? low 4.0a supply current ? precision monitoring of 2.85v to 5.0v power- supply voltages ? reset thresholds available from 2.63v to 4.80v, in approximately 100mv increments ? debounced manual reset input ? fully specified over temperature ? three power-on reset timeout periods available (1ms min, 20ms min, 100ms min) ? low cost ? three available output structures: push/pull reset , push/pull reset, open-drain reset ? guaranteed reset/ reset valid to v cc = 0.7v (max6803/max6804) ? power-supply transient immunity ? no external components required ? 4-pin sot143 package ? pin compatible with max811/max812 and max6314/max6315 max6803/max6804/max6805 4-pin, low-power p reset circuits with manual reset ________________________________________________________________ maxim integrated products 1 19-1946; rev 2; 12/05 part* max6803 us_ _d_-t max6804 us_ _d_-t max6805 us_ _d_-t -40? to +125? -40? to +125? -40? to +125? temp range pin-package 4 sot143 4 sot143 4 sot143 ordering information * these devices are available in factory-set v cc reset thresh- olds from 2.63v to 4.80v, in approximately 0.1v increments. choose the desired reset threshold suffix from table 1 and insert it in the blanks following ?s?in the part number. factory-programmed reset timeout periods are also available. insert the number corresponding to the desired nominal reset timeout period (1 = 1ms min, 2 = 20ms min, 3 = 100ms min) in the blank following ??in the part number. there are 15 stan- dard versions with a required order increment of 2500 pieces. sample stock is generally held on the standard versions only (see selector guide). contact the factory for availability of non- standard versions (required order increment is 10,000 pieces). all devices available in tape-and-reel only. devices are available in both leaded and lead-free packaging. specify lead-free by replacing ?t?with ?t?when ordering. typical operating circuit and pin configuration appear at end of data sheet. selector guide appears at end of data sheet. 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.
max6803/max6804/max6805 4-pin, low-power p reset circuits with manual reset 2 _______________________________________________________________________________________ absolute maximum ratings electrical characteristics ( v cc = full range, t a = -40? to +125?, unless otherwise noted. typical values are at v cc = +5.0v and t a = +25?, reset not asserted.) (note 1) 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. terminal voltage (with respect to gnd) v cc ......................................................................-0.3v to +6v push/pull reset or reset , mr ............-0.3v to (v cc + 0.3v) open-drain reset ..............................................-0.3v to +6v input current (v cc ) .............................................................20ma output current (reset, reset ) .........................................20ma continuous power dissipation (t a = +70?) 4-pin sot143 (derate 4mw/? above +70?) ............320mw 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 max6803/max6804 0.7 5.5 t a = 0? to +125? max6805 1.0 5.5 max6803/max6804 0.78 5.5 supply voltage range (note 1) v cc t a = -40? to +125? max6805 1.2 5.5 v v cc = +3.0v 4 10 supply current i cc no load v cc = +5.0v 5 12 ? t a = +25? v th - 1.8% v th v th + 1.8% reset threshold v th max680_us_ _d_-t, table 1 t a = - 40 c to + 1 25 c v th - 3% v th v th + 3% v v cc falling reset delay v cc falling at 10v/ms 30 ? max680_us_ _d1-t 1 1.5 2 max680_us_ _d2-t 20 30 40 reset active timeout period t rp max680_us_ _d3-t 100 150 200 ms mr minimum pulse width 1 s mr glitch immunity 50 ns mr reset delay 0.1 ? v il 0.3 ? v cc mr input voltage v ih 0.7 ? v cc v mr pullup resistance 12 20 30 k ? i sink = 50?, v cc 1.0v 0.4 i sink = 1.2ma, v cc 2.5v 0.3 reset output low voltage (max6804/max6805) v ol reset asserted i sink = 3.2ma, v cc 4.25v 0.4 v i sourc e = 500 a, v cc 3. 0v 0.8 ? v cc reset output high voltage (max6804) v oh reset not asserted i sourc e = 800 a, v cc 5. 0v 0.8 ? v cc v
4-pin, low-power p reset circuits with manual reset _______________________________________________________________________________________ 3 3.0 4.0 3.5 5.0 4.5 6.0 5.5 6.5 -50 0 25 -25 50 75 100 125 supply current vs. temperature max6803/04/05 toc01 temperature ( c) i cc ( a) v cc = +5.0v v cc = +3.3v 0.950 0.980 0.970 0.960 1.000 0.990 1.040 1.030 1.020 1.010 1.050 -50 -25 0 25 50 75 100 125 normalized reset timeout period vs. temperature max6803/04/05 toc02 temperature ( c) normalized reset timeout period 80 60 40 20 0 1.0 1.5 2.5 3.0 output-voltage low vs. supply voltage max6803/04/05 toc03 v cc (v) output-voltage low (mv) +25 c -40 c +125 c +85 c v th = 2.93v i sink = 500 a reset 2.0 100 75 50 25 0 1.0 2.0 1.5 2.5 output-voltage high vs. supply voltage max6803/04/05 toc04 v cc (v) output-voltage high (v cc - v oh ) (mv) +25 c -40 c +125 c +85 c v th = 2.93v i sink = 100 a reset asserted (max6803) 3.0 100 1000 0 100 200 400 300 500 600 0.1 1 10 maximum transient duration vs. reset comparator overdrive max6803/04/05 toc05 reset comparator overdrive (mv) maximum transient duration ( s) reset occurs reset does not occur 0 30 20 10 50 40 90 80 70 60 100 -50 -25 0 25 50 75 100 125 v cc falling propagation delay vs. temperature max6803/04/05 toc06 temperature ( c) poropagation delay ( s) v cc = falling at 1v/ms v cc = falling at 10v/ms __________________________________________typical operating characteristics (reset not asserted, t a = +25?, unless otherwise noted.) max6803/max6804/max6805 electrical characteristics (continued) ( v cc = full range, t a = -40? to +125?, unless otherwise noted. typical values are at v cc = +5.0v and t a = +25?, reset not asserted.) (note 1) parameter symbol conditions min typ max units i sourc e = 1 a, v cc 1. 0v 0.8 ? v cc i sourc e = 200 a, v cc 1. 8v 0.8 ? v cc v oh reset asserted i sourc e = 800 a, v cc 4.25v 0.8 ? v cc v i sink = 1.2ma, v cc 3.0v 0.3 reset output voltage (max6803) v ol reset not asserted i sink = 3.2ma, v cc 5.0v 0.4 v reset output leakage current (max6805) v cc > v th , reset not asserted 0.5 ? note 1: all parts are production tested at t a = +25?. over temperature limits are guaranteed by design and not production tested. note 2: i source for the max6803 is 100na; i sink for the max6804 is 100na; i sink for the max6805 is 50?.
max6803/max6804/max6805 4-pin, low-power p reset circuits with manual reset 4 _______________________________________________________________________________________ pin description applications information manual reset input many ?-based products require manual reset capabil- ity, allowing the operator, a test technician, or external logic circuitry to initiate a reset. a logic low on mr asserts reset. reset remains asserted while mr is low, and for the reset active timeout period after mr returns high. mr has an internal 20k ? pullup resistor, so it can be left unconnected if not used. connect a normally open momentary switch from mr to gnd to create a manual reset function; external debounce circuitry is not required. interfacing to ps with bidirectional reset pins since the reset output on the max6805 is open-drain, this device interfaces easily with ?s that have bidirec- tional reset pins, such as the motorola 68hc11. connecting the ? supervisor? reset output directly to the microcontroller? (??) reset pin with a single pullup resistor allows either device to assert reset (figure 1). negative-going v cc transients in addition to issuing a reset to the ? during power-up, power-down, and brownout conditions, these devices are relatively immune to short-duration, negative-going v cc transients (glitches). the typical operating characteristics show the maximum transient duration vs. reset comparator overdrive graph. the graph shows the maximum pulse width that a negative-going v cc transient may typically have without issuing a reset signal. as the amplitude of the transient increases, the maximum allowable pulse width decreases. ensuring a valid reset output down to v cc = 0 when v cc falls below 1v and approaches the minimum operating voltage of 0.7v, push/pull-structured reset sinking (or sourcing) capabilities decrease drastically. high-impedance cmos-logic inputs connected to the reset pin can drift to indeterminate voltages. this does not present a problem in most cases, since most v cc v cc gnd max6805 reset mr v cc gnd reset motorola 68hcxx p 100k ? figure 1. interfacing to ?s with bidirectional reset pins pin max6803 max6804 max6805 name function 1 1 gnd ground 2 reset active-low reset output. reset is asserted while v cc is below the reset threshold, or while mr is asserted. reset remains asserted for a reset timeout period (t rp ) after v cc rises above the reset threshold or mr is deasserted. reset on the max6804 is push/pull. reset on the max6805 is open-drain. active-high reset output. reset is asserted high while v cc is below the reset threshold or while mr is asserted, and reset remains asserted for a reset timeout period (t rp ) after v cc rises above the reset threshold or mr is deasserted. reset on the max6803 is push/pull. reset 2 3 3 mr manual reset input. a logic low on mr asserts reset. reset remains asserted as long as mr is low, and for the reset timeout period (t rp ) after mr goes high. leave unconnected or connect to v cc if not used. supply voltage input v cc 4 4
4-pin, low-power p reset circuits with manual reset _______________________________________________________________________________________ 5 max6803/max6804/max6805 v cc gnd max6804 reset mr 100k ? (a) v cc gnd max6803 reset 100k ? * (b) *assumes high-z reset input to the p mr figure 2. ensuring reset valid down to v cc = 0 ?s and circuitry do not operate when v cc drops below 1v. for the max6804 application where reset must be valid down to 0, adding a pulldown resistor between reset and gnd removes stray leakage currents, hold- ing reset low (figure 2a). the pulldown resistor value is not critical; 100k ? is large enough not to load reset , and small enough to pull it low. for the max6803, where reset must be valid to v cc = 0, a 100k ? pullup resistor between reset and v cc will hold reset high when v cc falls below 0.7v (figure 2b). since the max6805 has an open-drain, active-low out- put, it typically uses a pullup resistor. with this device, reset will most likely not maintain an active condition, but will drift to a non-active level due to the pullup resistor and the reduced sinking capability of the open- drain device. therefore, this device is not recommend- ed for applications where the reset pin is required to be valid down to v cc = 0. 1 2 4 3 v cc mr (reset) gnd max6803 max6804 max6805 sot143 top view reset ( ) are for max6803 max6804 v cc v cc reset mr reset gnd pushbutton switch v cc gnd p pin configuration t ypical operating circuit
max6803/max6804/max6805 4-pin, low-power p reset circuits with manual reset 6 _______________________________________________________________________________________ t a = +25 ct a = -40 c to +125 c reset threshold suffix min typ (v th )max mi nmax 48 4.714 4.80 4.886 4.656 4.944 47 4.615 4.70 4.785 4.559 4.841 46 4.547 4.63 4.713 4.491 4.769 45 4.419 4.50 4.581 4.365 4.635 44 4.301 4.38 4.459 4.249 4.511 43 4.223 4.30 4.377 4.171 4.429 42 4.124 4.20 4.276 4.074 4.326 41 4.026 4.10 4.174 3.977 4.223 40 3.928 4.00 4.072 3.880 4.120 39 4.830 3.90 3.970 3.783 4.017 38 3.732 3.80 3.868 3.686 3.914 37 3.633 3.70 3.767 3.589 3.811 36 3.535 3.60 3.665 3.492 3.708 35 3.437 3.50 3.563 3.395 3.605 34 3.339 3.40 3.461 3.298 3.502 33 3.241 3.30 3.359 3.201 3.399 32 3.142 3.20 3.258 3.104 3.296 31 3.025 3.08 3.135 2.988 3.172 30 2.946 3.00 3.054 2.910 3.090 29 2.877 2.93 2.983 2.842 3.018 28 2.750 2.80 2.850 2.716 2.884 27 2.651 2.70 2.749 2.619 2.781 26 2.583 2.63 2.677 2.551 2.709 table 1. factory-trimmed reset thresholds
max6803/max6804/max6805 4-pin, low-power p reset circuits with manual reset _______________________________________________________________________________________ 7 * sample stock is generally held on all standard versions. part output stage nominal v th (v) min reset timeout (ms) sot top mark max6803us26d3-t push/pull reset 2.63 100 kach max6803us29d3-t push/pull reset 2.93 100 kaci max6803us31d3-t push/pull reset 3.08 100 kacj max6803us44d3-t push/pull reset 4.38 100 kack max6803us46d3-t push/pull reset 4.63 100 kacl max6804us26d3-t push/pull reset 2.63 100 kacn max6804us29d3-t push/pull reset 2.93 100 kacp max6804us31d3-t push/pull reset 3.08 100 kacq max6804us44d3-t push/pull reset 4.38 100 kacr max6804us46d3-t push/pull reset 4.63 100 kacs max6805us26d3-t open-drain reset 2.63 100 kaco max6805us29d3-t open-drain reset 2.93 100 kacu max6805us31d3-t open-drain reset 3.08 100 kacv max6805us44d3-t open-drain reset 4.38 100 kacw max6805us46d3-t open-drain reset 4.63 100 kacx selector guide (standard versions * ) transistor count: 505 process: bicmos chip information
max6803/max6804/max6805 4-pin, low-power p reset circuits with manual reset 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. 8 _____________________maxim integrated products, 120 san gabriel drive, sunnyvale, ca 94086 408-737-7600 2005 maxim integrated products printed usa is a registered trademark of maxim integrated products, inc. sot-143 4l.eps e 1 1 21-0052 package outline, sot-143, 4l 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 .)
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