computers controllers intelligent instruments critical p and c power monitoring portable/battery- powered equipment bar-code scanners general description the max6806/max6807/max6808 precision voltage detectors are ideal for accurate monitoring of power supplies in digital systems. they provide circuit reliability and reduce total cost by eliminating external components and adjustments. the max6806/max6807/max6808 assert a reset signal whenever the supply voltage (v cc ) falls below the factory- preset, 2% accurate threshold. internal hysteresis ensures stable switching. the max6806/max6807/ max6808 are available in 4.6v and 2.6v thresholds (2.3v is also available for the max6806 only). the max6806 features an active-low, push-pull reset output; the max6807 features an active-high, push-pull reset output; and the max6808 features an active-low, open- drain reset output. reset is valid for v cc down to 1v (max6806/max6808), and reset (max6807) is guar - anteed for v cc down to 1.2v. the max6806/max6807/max6808 are available in 3-pin sc70, 3-pin sot23, 8-pin max, 8-pin so, and 4-pin sot143 packages. the sot143 package includes a manual-reset input. applications features preset reset thresholds: 4.6v and 2.6v (2.3v also available for max6806 only) 2% accurate reset thresholds reset output available in active-low (max6806), active-high (max6807), and open-drain (max6808) versions immune to power-supply transients reset valid to v cc = 1.0v (max6806/max6808) 35a supply current no external components manual reset available with 4-pin sot143 package miniature 3-pin sc70, 3-pin sot23, and 4-pin sot143 packages 8-pin max and 8-pin so packages are pin compatible with the mc33064/mc33164/ mc34064/mc34164 * sot23, sot143, and sc70s are available in tape-and-reel only, 2500 piece minimum order quantity. note: insert the desired number from the selector guide into the blank to complete the part number. also see selector guide for top mark for sot23 part temp. range pin-package max6806 xr_ _ -t -40c to +85c 3 sc70 max6806ur_ _ -t -40c to +85c 3 sot23 max6806us_ _ -t -40c to +85c 4 sot143 max6806ua_ _ -40c to +85c 8 max max6806sa_ _ -40c to +85c 8 so max6807 xr_ _ -t -40c to +85c 3 sc70 max6807ur_ _ -t -40c to +85c 3 sot23 max6807us_ _ -t -40c to +85c 4 sot143 max6807ua_ _ -40c to +85c 8 max max6807sa_ _ -40c to +85c 8 so max6808 xr_ _ -t -40c to +85c 3 sc70 max6808ur_ _ -t -40c to +85c 3 sot23 max6808us_ _ -t -40c to +85c 4 sot143 max6808ua_ _ -40c to +85c 8 max max6808sa_ _ -40c to +85c 8 so max6806 max6807 max6808 v cc v cc v cc gnd gnd p (reset)/ reset reset input ( ) are for max6807 19-1421; rev 3; 7/14 ordering information typical operating circuit selector guide and pin configurations appear at end of data sheet. max6806/max6807/ max6808 voltage detectors
v cc to gnd ........................................................ -0.3v to +6.0v reset, reset to gnd (max6806/max6807) ............................. -0.3v to (v cc + 0.3v) reset to gnd (max6808) ................................ -0.3v to + 6.0v mr to gnd (sot143 package only) .................. -0.3v to + 6.0v input current, v cc .......................................................... 20ma output current, reset, reset ..................................... 20ma rate of rise, v cc ......................................................... 100v/s continuous power dissipation (t a = +70c) sot23, sot143 (derate 4mw/c above +70c) ...... 320mw sc70 (derate 2.17mw/c above +70vc) ................... 174mw max (derate 4.5mw/c above +70c) .................... 362mw so (derate 5.9mw/c above +70c) ......................... 471mw operating temperature range .......................... -40c to +85c storage temperature range ............................ -65c to +160c lead temperature (soldering, 10s) ................................. +300c note1: all devices are 100% production tested at t a = +25c, and are guaranteed by design for t a = t min to t max , as specified. note 2: reset output for max6806/max6808, reset output for max6807. (v cc = +5v, t a = -40c to +85c, unless otherwise noted. typical values are at t a = +25c.) (note 1) parameter symbol conditions min typ max units supply voltage range v cc t a = 0c to +70c 1.0 5.5 v t a = -40c to +85c 1.2 5.5 supply current i cc v cc = +3.6v, no load 35 60 a v cc = +5.5v, no load 50 80 reset threshold v th- t a = +25c v cc falling max680 _ _ _ 46 4.508 4.60 4.692 v max680 _ _ _ 32 3.136 3.20 3.264 max680_ _ _26 2.548 2.60 2.652 max680_ _ _23 2.254 2.30 2.346 reset threshold hysteresis v hyst t a = +25c, figure 2 0.02 v th- 0.03 v th- v reset output voltage (max6806/max6808) v ol i sink = 20a, v cc = 1.0v 0.3 v i sink = 1.0ma, v cc = 2.0v 0.4 v oh i source = 2.0ma, v cc = 5.0v (max6806 only) 0.8 v cc reset output leakage current i oh v cc = 5.5v, reset deasserted (max6808 only) 1 a reset output voltage (max6807) v oh i source = 20a, v cc = 1.2v 0.8 v cc v i source = 400a, v cc = 2.0v 0.8 v cc v ol i sink = 3.2ma, v cc = 5.0v 0.4 v cc to reset delay (note 2) v cc falling at 1mv/s 30 s reset threshold tempco 30 ppm/c mr pulldown resistance r mr 40 80 120 k w mr input threshold v il v cc > v th+ 0.6 v v ih 0.7 v cc maxim integrated 2 electrical characteristics stresses beyond those listed under absolute 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 ab solute maximum rating conditions for extended periods may affect device reliability. absolute maximum ratings www.maximintegrated.com max6806/max6807/ max6808 voltage detectors
(t a = +25c, unless otherwise noted.) pin name function sot23/sc70 sot143 max /so 1 1 1 reset active-low reset output (max6806/max6808). reset remains low while v cc is below the reset-threshold voltage or while mr is held high. reset active-high reset output (max6807). reset remains high while v cc is below the reset-threshold voltage or while mr is held high. 2 4 4 gnd ground 3 3 2 v cc supply voltage input 2 mr active-high manual reset input. internal 80k w resistor to gnd. 3,5C8 n.c. not internally connected 0.9900 0.9940 0.9920 0.9980 0.9960 1.0020 1.0000 1.0040 1.0080 1.0060 1.0100 -40 -15 0 -30 15 30 60 45 85 75 normalized reset threshold vs. temperature max6806/7/8-04 temperature (c) normalized reset threshold v cc rising (v th+ ) v cc falling (v th- ) 4 6 5 7 9 8 11 10 12 -60 -30 0 30 60 120 90 power-up reset delay vs. temperature max6806/7/8-03 temperature (c) delay time ( s) v od = v cc - v th + v od = 50mv v od = 200mv v od = 100mv 25 29 27 33 31 35 37 43 41 39 45 -60 -30 -15 0 -45 15 30 45 75 60 90 105 120 135 power-down reset delay vs. temperature max6806/7/8toc02 temperature (c) reset delay ( s) v od = v th- - v cc = 100mv v cc falling at 1mv/s 0 10 5 20 15 30 25 35 45 40 50 -60 -30 0 30 60 120 90 supply current vs. temperature max6806/7/8-01 temperature (c) supply current ( a) v cc = 5.0v v cc = 3.3v v cc = 1.8v v cc = 1.0v maxim integrated g 3 pin description typical operating characteristics www.maximintegrated.com max6806/max6807/ max6808 voltage detectors
detailed description reset output the max6806 voltage detector features an active-low, push-pull reset output, while the max6807 features an active-high, push-pull reset output. unlike micropro - cessor (p) supervisory circuits that offer a reset timeout period, the max6806 and max6807 reset goes high and reset goes low virtually immediately once v cc exceeds the reset threshold. if a brownout occurs (v cc falls below the reset threshold), reset goes low and reset goes high. reset is guaranteed to be a logic low for v cc 1v and reset is guaranteed to be a logic high for v cc 1.2v. the max6808 features an active-low, open-drain reset output. the output sinks current when v cc falls below the reset threshold. connect a pullup resistor from reset to any supply voltage up to 6v (figure 1). select a resistor value large enough to provide a logic low and small enough to provide a logic high while supplying all input and leakage currents connected to the reset line. a 100k w resistor is sufficient in applications driving high-impedance loads. the manual reset input (mr, 4-pin sot143 package) can also initiate a reset (see manual reset input section). manual-reset input many applications require manual-reset capabilities, allowing an operator, a test technician, or external logic circuitry to initiate a reset. a logic high on mr asserts a reset and remains asserted while mr is high. this input has an 80k w pulldown resistor, so the input can be left unconnected if not used. connect a normally open momentary switch from mr to v cc to create a manu - al-reset function. if mr is driven from long cables or if the device is used in a noisy environment, connecting a 0.1f capacitor from mr to ground provides noise immunity. hysteresis the max6806/max6807/max6808 feature internal hysteresis that creates two trip points: one for the rising supply voltage and one for the falling supply voltage (figure 2). the hysteresis prevents the output from oscillating (chattering) when v cc is near the reset threshold. reset threshold accuracy the max6806/max6807/max6808 are ideal for sys-tems using a 5v 5%, 3v 5%, or 2.5v 5% power supply with ics specified for 5v 10%, 3v 10%, or 2.5v 10%, respectively. the reset is guaranteed to assert after the power supply falls out of regulation, but before power drops below the minimum specified oper-ating voltage range for the system ics. figure 2. input and output waveforms with v cc varied figure 1. the max6808 open-drain reset output allows use with multiple supplies v th+ hyst reset (max6806/max6808) reset (max6807) v hyst = v th+ - v th- v oh v ol v oh v ol v th- max6808 v cc v cc gnd +3.3v gnd +5.0v 100k? 5v system reset maxim integrated 4 www.maximintegrated.com max6806/max6807/ max6808 voltage detectors
applications information negative-going v cc transients in addition to asserting a reset signal during power-up, power-down, and brown-out conditions, the max6806/ max6807/max6808 are immune to short-duration, neg- ative-going v cc transients. figure 3 displays typical transient durations vs. reset-com - parator overdrive for which the max6806/max6807/ max6808 do not generate a reset pulse. the graph was generated using a negative-going pulse applied to v cc , starting 0.5v above the actual reset threshold and ending below it by the magnitude indicated (reset-comparator overdrive). the graph indicates the maximum pulse width a negative-going v cc transient can have without causing a reset pulse. as the magnitude of the transient increases (goes further below the reset threshold), the maximum allowable pulse width decreases. a 0.1f capacitor mounted as close as possible to v cc provides additional transient immunity. ensuring a valid reset output down to v cc = ground when v cc falls below 1v, the max6806/max6808 reset output no longer sinks currentit becomes an open circuit. therefore, high-impedance cmos logic inputs connected to r eset can drift to undetermined voltages. this presents no problem in most applications, since most circuitry is inoperative when v cc is below 1v. in applications where reset must be valid down to ground, add a pulldown resistor to reset so any stray leakage currents flow to ground, holding reset low (figure 4). select r1 to be large enough not to load reset and small enough to pull reset to ground. for most applications, 100k w will not load reset and will pull reset to ground. similarly, if reset (max6807) must be valid below 1.2v, add a pullup resistor to reset. figure 4. reset / reset valid to v cc = ground circuit figure 3. maximum transient duration without causing a reset pulse vs. reset comparator overdrive max6806 max6807 v cc v cc gnd gnd reset reset r1 100k? r1 100k? 80 70 20 10 100 1000 40 30 50 60 reset comparator overdrive, v th- - v cc (mv) maximum transient duration (s) t a = +25c max680 46 maxim integrated 5 www.maximintegrated.com max6806/max6807/ max6808 voltage detectors
interfacing to ps with bidirectional reset pins ps with bidirectional reset pins (such as the motorola 68hc11 series) can contend with push-pull reset outputs, resulting in indeterminate logic levels. use the max6808 with the open-drain reset when interfacing to this type of controller. figure 5. interfacing to ps with bidirectional reset i/o part reset output top mark nominal v th- (v)? max6806sa46 active-low, push-pull 4.6 max6806sa26 2.6 max6806sa23 2.3 max6806ua46 4.6 max6806ua26 2.6 max6806ua23 2.3 max6806ur46-t fzdp 4.6 max6806ur26-t fzdq 2.6 max6806ur23-t fzdr 2.3 max6806us46-t kabt 4.6 max6806us26-t kabu 2.6 max6806us23-t kabv 2.3 max6806xr46-t aaa 4.6 max6806xr26-t aab 2.6 max6806xr23-t aac 2.3 max6808 v cc v cc v cc gnd gnd 4.7k? p reset reset maxim integrated 6 selector guide www.maximintegrated.com max6806/max6807/ max6808 voltage detectors
other voltage thresholds may be available. contact factory for availability. part reset output top mark nominal v th- (v) ? max6807sa46 active-high, push-pull 4.6 max6807sa26 2.6 max6807ua46 4.6 max6807ua26 2.6 max6807ur46-t fzds 4.6 max6807ur26-t fzdt 2.6 max6807us46-t kabw 4.6 MAX6807US26-T kabx 2.6 max6807xr46-t aad 4.6 max6807xr26-t aae 2.6 max6808sa46 active-low, open-drain 4.6 max6808sa32 3.2 max6808sa26 2.6 max6808ua46 4.6 max6808ua32 3.2 max6808ua26 2.6 max6808ur46-t fzdu 4.6 max6808ur32-t fzfl 3.2 max6808ur26-t fzdv 2.6 max6808us46-t kaby 4.6 max6808us32-t kacc 3.2 max6808us26-t kabz 2.6 max6808xr46-t aaf 4.6 max6808xr32-t acd 3.2 max6808xr26-t aag 2.6 maxim integrated 7 selector guide (continued) www.maximintegrated.com max6806/max6807/ max6808 voltage detectors
package type package code outline no. land pattern no. 3 sc70 x3-2 21-0075 90-0208 3 sot23 u3-1 21-0051 90-0179 4 sot143 u4-1 21-0052 90-0183 8 so 21-0041 8 max 21-0036 top view gnd 1 3 v cc (reset)/ reset max6806 max6807 max6808 sot23/sc70 2 ( ) are for max6807 1 2 4 3 gnd v cc mr (reset)/ reset max6806 max6807 max6808 sot143 max6806 max6807 max6808 max/so 8 n.c. 5 n.c. 4 gnd 1 (reset)/ reset 2 v cc 3 n.c. 6 n.c. 7 n.c. maxim integrated 8 chip information transistor count: 72 pin confgurations package information for the latest package outline information and land patterns (footprints), go to www.maximintegrated.com/packages . note that a +, #, or - in the package code indicates rohs status only. package drawings may show a different suffix character, but the drawing pertains to the package regardless of rohs status. www.maximintegrated.com max6806/max6807/ max6808 voltage detectors
revision number revision date description pages changed 3 7/14 no /v opns; removed automotive reference from applications section; updated package information 1, 9C13 ? 2014 maxim integrated products, inc. 9 revision history maxim integrated cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a maxim integrated product. no circuit patent licenses are implied. maxim integrated reserves the right to change the circuitry and specifcations without notice at any time. the parametric values (min and max limits) shown in the electrical characteristics table are guaranteed. other parametric values quoted in this data sheet are provided for guidance. maxim integrated and the maxim integrated logo are trademarks of maxim integrated products, inc. max6806/max6807/ max6808 voltage detectors for pricing, delivery, and ordering information, please contact maxim direct at 1-888-629-4642, or visit maxim integrateds website at www.maximintegrated.com.
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