general description the max6710 precision quad-voltage monitor with micro- processor (?) supervisory reset timing monitors up to four system-supply voltages and asserts a single reset if any supply voltage drops below its preset threshold. the device significantly reduces system size and component count while improving reliability compared to separate ics or discrete components. a variety of factory-trimmed threshold voltages are avail- able to accommodate different supply voltages and toler- ances with minimal external component requirements. the selection includes internally fixed options for monitor- ing 5.0v, 3.3v, 3.0v, 2.5v, and 1.8v supplies with -5% or -10% tolerances. the device is also available with one to three adjustable threshold options to monitor voltages down to 0.62v. a single active-low reset output asserts when any moni- tored input is below its associated threshold. the output is open drain with a weak internal pullup (10?) to in2. reset remains low for a reset timeout period (140ms min) after all voltages are above the selected thresholds. the output is valid as long as either the in1 or in2 input volt- age remains >1v. the max6710 is available in a small 6-pin sot23 pack- age and operates over the extended (-40? to +85?) temperature range. ________________________applications telecommunications high-end printers desktop and network computers data storage equipment networking equipment industrial equipment set-top boxes features monitors four power-supply voltages precision factory-set reset threshold options for 5.0v, 3.3v, 3.0v, 2.5v, and 1.8v supplies adjustable voltage threshold monitors down to 0.62v with 1.5% accuracy low 35? supply current open-drain reset output with 10? internal pullup 140ms (min) reset timeout period reset valid to in1 = 1v or in2 = 1v immune to short monitored supply transients guaranteed from -40? to +85? small 6-pin sot23 package max6710 low-voltage, high-accuracy, quad-voltage p supervisory circuit in sot package ________________________________________________________________ maxim integrated products 1 19-2324; rev 0; 1/02 ordering information * insert the desired suffix letter from the selector guide into the blank to complete the part number. there is a 2500 piece mini- mum order increment requirement on the sot package and these devices are available in tape-and-reel only. pin configuration appears at end of data sheet. part temp range pin-package max6710_ut-t* -40 c to +85 c 6 sot23-6 max6710 in1 in2 in3 in4 reset gnd supplies to be monitored p typical operating circuit 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. selector guide appears at end of data sheet.
max6710 low-voltage, high-accuracy, quad-voltage p supervisory circuit in sot package 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. terminal voltage (with respect to gnd) input voltages (in_ ).................................................-0.3v to +6v reset .......................................................................-0.3v to +6v continuous reset current .................................................20ma continuous power dissipation (t a = +70 c) 6-pin sot23 (derate 8.7mw/ c above +70 c).........695.7mw operating temperature range ...........................-40 c to +85 c storage temperature range .............................-65 c to +150 c junction temperature ......................................................+150 c lead temperature (soldering, 10s) .................................+300 c parameter sym b o l conditions min typ max units v cc max6710q 2.0 5.5 t a = 0 o c to +85 o c 1.0 5.5 operating voltage range (notes 2, 3) v in2 all others t a = -40 o c to +85 o c 1.2 5.5 v in_ = nominal input voltage (for 1.8v, 2.5v, and 5.0v supplies) 25 40 in2 = nominal input voltage (for 3.0v and 3.3v supplies) (note 4) 55 115 v in1 = 0 to 0.85v (for adjustable thresholds) 0.4 i in_ v in3 , v in4 = 0 to 0.85v (for adjustable thresholds) 0.2 input current i cc max6710q only, v cc = 5.5v 35 50 a 5v (-5%) 4.50 4.63 4.75 5v (-10%) 4.25 4.38 4.50 3.3v (-5%) 3.00 3.08 3.15 3.3v (-10%) 2.85 2.93 3.00 3.0v (-5%) 2.70 2.78 2.85 3.0v (-10%) 2.55 2.63 2.70 2.5v (-5%) 2.25 2.32 2.38 2.5v (-10%) 2.13 2.19 2.25 1.8v (-5%) 1.62 1.67 1.71 threshold voltage v th in_ decreasing 1.8v (-10%) 1.53 1.58 1.62 v adjustable threshold v th in_ decreasing 0.611 0.620 0.624 v reset threshold hysteresis v hyst in_ increasing relative to in_ decreasing 0.3 %v th reset threshold temperature coefficient tcv th 60 ppm/ o c in_ to reset delay t rd v in _ fal l i ng at 10m v /s fr om v th to ( v th - 50m v ) 30 s reset timeout period t rp 140 200 280 ms electrical characteristics (v in2 = 1v to 5.5v, t a = -40 c to +85 c, unless otherwise noted. typical values are at v in2 = 3.0v to 3.3v, t a = +25 c.) (note 1)
max6710 low-voltage, high-accuracy, quad-voltage p supervisory circuit in sot package _______________________________________________________________________________________ 3 note 1: 100% production tested at t a = +25 c. limits over temperature guaranteed by design. note 2: the device is powered from input in2 or v cc (for max6710q). note 3: the reset output is guaranteed to be in the correct state for in1 or in2 down to 1v. note 4: monitored in2 voltage (3.3v, 3.0v) is also the device power supply. supply current splits as follows: 25a for the resistor divider (for the monitored voltage) and 30a for other circuits. 40 46 44 42 48 50 52 54 56 58 60 -40 -15 10 35 60 85 in2 input current vs. temperature max6710 toc01 temperature (?) in2 input current ( a) v in2 = 3.3v v in2 = 3v 0 20 10 50 40 30 60 70 80 90 0 1.0 1.5 0.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 in2 input current vs. in2 voltage max6710 toc02 in2 voltage (v) in2 input current ( a) -0.10 -0.04 -0.06 -0.08 -0.02 0 0.02 0.04 0.06 0.08 0.10 -40 -15 10 35 60 85 normalized threshold error vs. temperature max6710 toc03 temperature ( c) normalized threshold error (%) v th = 1.8v v in2 = 3.3v typical operating characteristics (v in2 = 3.0v, t a = +25 c) parameter sym b o l conditions min typ max units v in2 , v cc = 5v, i sink = 2ma 0.3 v in2 , v cc = 2.5v, i sink = 1.2ma 0.4 reset output low v ol v in2 = 1.0v, i sink = 50a, t a = 0 o c to +85 o c 0.3 v v cc 2.0v, i source = 6a, reset deasserted (max6710q) 0.8 ? v cc reset output high v oh v in2 2.0v, i source = 6a, reset deasserted 0.8 ? v in2 v reset output high source current i oh v in2 2.0v, reset deasserted 10 a electrical characteristics (continued) (v in2 = 1v to 5.5v, t a = -40 c to +85 c, unless otherwise noted. typical values are at v in2 = 3.0v to 3.3v, t a = +25 c.) (note 1)
pin description pin name function 1 in1 input voltage 1. see selector guide for monitored voltages. in2 2 v cc inp ut v ol tag e 2. s ee s el ector g ui d e for m oni tor ed vol tag es. in 2 i s the p ow er - sup p l y i np ut for the d evi ce. v c c i s the p ow er - sup p l y i np ut for the d evi ce and i s not a m oni tor ed vol tag e ( m ax 6710q onl y) . 3 in3 input voltage 3. see selector guide for monitored voltages. 4 in4 input voltage 4. see selector guide for monitored voltages. 5 gnd ground 6 reset reset output, active low. reset goes low when any input goes below its specified threshold. after all inputs are above their threshold voltage, reset remains low for at least 140ms (minimum) before going high. reset output is open-drain with a weak internal pullup to in2, v cc . max6710 low-voltage, high-accuracy, quad-voltage p supervisory circuit in sot package 4 _______________________________________________________________________________________ typical operating characteristics (continued) (v in2 = 3.0v, t a = +25 c) 220 222 221 223 224 225 226 227 228 229 230 231 232 max6710 toc07 temperature ( c) -40 10 -15 35 60 85 reset timeout delay vs. temperature reset timeout delay (ms) 40ms/div max6710 toc08 reset 2v/div reset timeout delay in_ 2v/div 0 20 10 40 30 60 50 70 90 80 100 0 200 300 400 100 500 600 700 900 800 1000 max6710 toc04 maximum in_ transient duration ( s) reset asserted above this line reset threshold overdrive (mv) maximum in_ transient duration vs. reset threshold overdrive 0 20 10 40 30 60 50 70 90 80 100 0 200 300 400 100 500 600 700 900 800 1000 max6710 toc05 reset threshold overdrive (mv) reset delay vs. reset threshold overdrive (in_ decreasing) reset delay ( s) in_ 100mv/div ac-coupled 10 s/div max6710 toc06 reset pullup and pulldown response (c l = 47pf) reset 2v/div
max6710 low-voltage, high-accuracy, quad-voltage p supervisory circuit in sot package _______________________________________________________________________________________ 5 detailed description the max6710 is a very small, low-power, quad-voltage p supervisory circuit designed to maintain system integrity in multisupply systems (figure 1). the device offers several internally trimmed undervoltage threshold options that minimize the need for external compo- nents. preset voltage monitoring options for 5.0v, 3.3v, 3.0v, 2.5v, and 1.8v make the device ideal for telecom- munications, desktop and notebook computers, high- end printers, data storage equipment, and networking equipment applications. the quad-voltage reset includes an accurate bandgap reference, four precision comparators, and a series of internally trimmed resistor-divider networks to set the fac- tory-fixed reset threshold options. the resistor networks scale the specified in_ reset voltages to match the inter- in1 (adj) in2, v cc (3.3v/3v) in3 (2.5v/1.8v) in4 (adj) 0.62v reference nor gate time- out (200ms) in2, v cc reset max6710 all devices are powered from in2, v cc (3.0v/3.3v). reset is valid if v in1 or v in2 is greater than 1v, or if v cc is greater than 2v (max6710q only) uvlo figure 1. max6710 functional diagram
max6710 low-voltage, high-accuracy, quad-voltage p supervisory circuit in sot package 6 _______________________________________________________________________________________ nal bandgap reference/comparator voltage. adjustable threshold options bypass the internal resistor networks and connect directly to one of the comparator inputs (an external resistor-divider network is required for threshold matching). the max6710q provides a separate unmoni- tored power-supply input (v cc ) and three adjustable volt- age inputs. each of the internal comparators has a typical hystere- sis of 0.3% with respect to its reset threshold. this built- in hysteresis improves the monitor s immunity to ambient noise without significantly reducing threshold accuracy when an input sits at its specified reset volt- age. the max6710 is also designed to ignore short in_ transients. see typical operating characteristics for a glitch immunity graph. applications information reset output the max6710 reset output asserts low when any monitored in_ voltage drops below its specified reset threshold and remains low for the reset timeout period (140ms minimum) after all inputs exceed their thresh- olds (figure 2). the output is open drain with a weak internal pullup to the monitored in2 or v cc supply (10a typ). for many applications no external pullup resistor is required to interface with other logic devices. an external pullup resistor to any voltage from 0 to 5.5v can overdrive the internal pullup if interfacing to differ- ent logic-supply voltages (figure 3). internal circuitry prevents reverse current flow from the external pullup voltage to in2. the max6710 is normally powered from the monitored in2 supply when all input voltages are above their specified thresholds. when any supply drops below its threshold, the reset output is asserted and guaranteed to remain low while either in1 or in2 is above 1.0v. adjustable thresholds the max6710 offers several monitor options with adjustable reset thresholds. the threshold voltage at each adjustable in_ input is typically 0.62v. to monitor a voltage >0.62v, connect a resistor-divider network to the circuit as shown in figure 4. v inth = 0.62v x (r1 + r2) / r2 or, solved in terms of r1: r1 = r2 ((v i nth / 0.62v) - 1) figure 2. reset output timing diagram figure 4. setting the auxiliary monitor v th_ 90% 10% in_ v th_ reset t rp t rd v ref = 0.62v r2 r1 v inth r1 = r2 ( - 1 ) v inth 0.62v figure 3. interfacing to different logic-supply voltage in2 gnd in2 = +3.3v +5v max6710 v cc gnd reset reset 100k ?
because the max6710 has a guaranteed input current of 0.2a (0.4a for in1) on its adjustable inputs, resistor values up to 100k ? can be used for r2 with <1% error. the max6710q includes an internal voltage clamp (1.5v typ) at each of the adjustable voltage inputs. an input voltage higher than 1.5v induces a higher input current. unused inputs connect unused monitor inputs to a supply voltage greater in magnitude than their specified threshold volt- ages. for unused in_ adjustable inputs, connect a 1m ? series resistor between the unused input and in2 (or v cc ) to limit the bias current. the in2 input must always be used for normal operation (device power- supply pin). unused monitor inputs cannot be connect- ed to ground or allowed to float. adding manual reset capability figure 5 shows an application circuit adding manual reset to the max6710 quad-voltage supervisor. depressing the pushbutton switch short-circuits the ana- log input to ground and initiates a reset pulse. the switch must be open for 200ms (typ) in order to deassert the reset output. no external switch debounce is required. use a small capacitor to improve noise immuni- ty when using long leads from the pushbutton switch to the adjustable input. power-supply bypassing and grounding the max6710 is normally powered from the monitored in2 or from the v cc supply input. all monitored inputs are immune to short supply transients. if higher immuni- ty is desired in noisy applications, connect a 0.1f bypass capacitor from the in2 input to ground. additionally, capacitance can be added to in1, in3, and in4 to increase their noise immunity. chip information transistor count: 699 process: bicmos max6710 low-voltage, high-accuracy, quad-voltage p supervisory circuit in sot package _______________________________________________________________________________________ 7 pin configuration figure 5. adding manual reset capability in1 in2 in3 max6710 gnd reset in4 (adjustable input) r1 r2 (v cc ) in2 in4 in3 16 5 gnd in1 ( ) are for max6710q only max6710 sot23 top view 2 34 reset
max6710 low-voltage, high-accuracy, quad-voltage p supervisory circuit in sot package 8 _______________________________________________________________________________________ nominal input voltage part (suffix in bold) in1 (v) in2 (v) in3 (v) in4 (v) supply tolerance (%) top mark max6710 a ut 5 3.3 2.5 adj* 10 aaza max6710 b ut 5 3.3 2.5 adj* 5 aazb max6710 c ut 5 3.3 1.8 adj* 10 aazc max6710 d ut 5 3.3 1.8 adj* 5 aazd max6710 e ut adj* 3.3 2.5 1.8 10 aaze max6710 f ut adj* 3.3 2.5 1.8 5 aazf max6710 g ut 5 3.3 adj* adj* 10 aazg max6710 h ut 5 3.3 adj* adj* 5 aazh max6710 i ut adj* 3.3 2.5 adj* 10 aazi max6710 j ut adj* 3.3 2.5 adj* 5 aazj max6710 k ut adj* 3.3 1.8 adj* 10 aazk max6710 l ut adj* 3.3 1.8 adj* 5 aazl max6710 m ut adj* 3 2.5 adj* 10 aazm max6710 n ut adj* 3 2.5 adj* 5 aazn max6710 o ut adj* 3 1.8 adj* 10 aazo max6710 p ut adj* 3 1.8 adj* 5 aazp max6710 q ut adj* v cc adj* adj* n/a aazq selector guide * adjustable voltage based on 0.62v internal threshold. external threshold voltage can be set using an external resistor-divider.
max6710 low-voltage, high-accuracy, quad-voltage p supervisory circuit in sot package 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 ? 2002 maxim integrated products printed usa is a registered trademark of maxim integrated products. 6lsot.eps package information
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