View MAX16024LTBS_8700281.PDF datasheet online --- IC-ON-LINE

Datasheet File OCR Text:

general description the max16023/max16024 low-power battery-backup cir-cuits with a regulated output are capable of delivering up to 100ma output current. the max16023/max16024 include a low-dropout regulator, a microprocessor (?) reset circuit, and a battery switchover circuit. additional available features include a manual reset, a power-fail comparator, and a battery-on indicator. these devices reduce the number of external components to minimize board space and improve reliability.the max16023/max16024 are ideally suited for provid- ing power for backing up critical memory such as static random-access memory (sram) or real-time clocks (rtcs). the regulated output is powered by v cc when it is present and switches over to the backup power dur-ing brownout. the max16023/max16024 accept an input voltage from 1.53v to 5.5v and provide fixed stan- dard output voltages of 1.2v, 1.8v, 2.5v, 3.0v, and 3.3v. the max16024 offers the ability to externally set the out- put voltage using a resistive divider. all outputs are available with push-pull or open-drain configurations. the max16023 offers a power-fail comparator for monitor- ing an additional voltage or for providing an early power- fail warning. another feature includes a manual-reset input (max16023/max16024). the max16024 also features a battery-on indicator and chip-enable gating function. the max16023/max16024 are offered in 8- and 10-pin tdfn packages and are fully specified from -40? to +85? temperature range. applications main/backup power for rtcs/sramindustrial controls gps systems set-top boxes point-of-sale equipment portable/battery equipment features ? system monitoring for 5v, 3.3v, 3v, 2.5v, or 1.8vpower-supply voltages ? 100ma low-dropout regulator ? factory-trimmed and adjustable output voltages ? 1.53v to 5.5v operating voltage range ? low-power consumption: 4? (typ) ? power-fail comparators for monitoring voltagesdown to 0.6v ? battery-on indicator ? battery freshness seal ? on-board gating of ce signals, 1.5nspropagation delay (max16024) ? debounced manual-reset input ? 145ms (min) reset timeout period ? tiny 8-pin and 10-pin tdfn packages ? ul certified to conform to iec 60950-1 max16023/max16024 battery-backup circuits with regulated output voltage ________________________________________________________________ maxim integrated products 1 19-4249; rev 0; 8/08 for pricing, delivery, and ordering information, please contact maxim direct at 1-888-629-4642, or visit maxim? website at www.maxim-ic.com. ordering information part temp range pin-package max16023 _ta_ _ _+t -40? to +85? 8 tdfn-ep* max16024 _tb_ _ _+t -40? to +85? 10 tdfn-ep* the first placeholder ??designates reset output options. a letter ??in this placeholder indicates a push-pull output and letter ? indicates an open-drain output. the next placeholder ??desig- nates the reset threshold (table 1). the last two placeholders ? _?designate output voltage (table 2). for the max16024 with adjustable output voltage version, there are no last two place- holders. + denotes a lead-free/rohs-compliant package. t = tape and reel. * ep = exposed pad. pin configurations 8 7 6 5 1 2 3 4 pfo gnd *ep *ep *ep = exposed pad reset out pfi mr batt v cc max16023 tdfn 10 9 8 7 1 2 3 4 gnd outreset ceout batt cein v cc mr 6 5 batt on set max16024 tdfn + + ul is a registered trademark of underwriters laboratories, inc. downloaded from: http:///
max16023/max16024 battery-backup circuits with regulated output voltage 2 _______________________________________________________________________________________ absolute maximum ratingselectrical characteristics (v cc = 1.53v to 5.5v, v batt = 3v, reset not asserted, t a = t j = -40? to +85?, c out = 10?, unless otherwise noted. typical val- ues are at t a = t j = +25?.) (note 2) stresses beyond those listed under ?bsolute 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 absolute maximum rating conditions for extended periods may affect device reliability. v cc , batt, out to gnd..........................................-0.3v to +6v reset , pfo , batt on (all open drain) to gnd..................................................................-0.3v to +6v reset , pfo , batt on (all push-pull) to gnd .................................................-0.3v to (v out + 0.3v) pfi, ce in, ce out to gnd.......................-0.3v to (v out + 0.3v) mr to gnd .................................................-0.3v to (v cc + 0.3v) input currentv cc peak current.....................................................................1a v cc continuous current ...............................................250ma batt peak current .......................................................500ma batt continuous current ...............................................70ma output current out short circuit to gnd duration ....................................10s reset , batt on, ce out..............................................20ma continuous power dissipation (t a = +70?) 8-pin tdfn (derate 24.4mw/? above +70?) .........1951mw 10-pin tdfn (derate 24.4mw/? above +70?) .......1951mw thermal resistance (note 1) ja (8-pin and 10-pin tdfn)........................................41?/w operating temperature range ...........................-40? to +85? junction temperature ......................................................+150? storage temperature range .............................-65? to +150? lead temperature (soldering, 10s) .................................+300? parameter symbol conditions min typ max units operating voltage range v cc , v batt (note 3) 1.53 5.5 v ldo = 1.2v 4.3 6 ldo = 1.8v 4.7 7 ldo = 2.5v 5.2 7.5 ldo = 3v 5.5 8 v cc = ldo + 0.5v, no load ldo = 3.3v 5.7 8 ldo = 1.2v 16 20 ldo = 1.8v 16 21 ldo = 2.5v 16 18.1 ldo = 3v 17 18.6 supply current i cc v cc = ldo + 0.5v, i out = 20ma ldo = 3.3v 17 19 ? supply current in battery-backupmode i batt v cc = 0, v batt = 3v, no dropout, no load 3.5 5.26 ? batt standby current v cc > v batt + 0.2v -0.01 +0.01 ? set reference voltage v set max16024_tb_, v cc = 2.2v 1.144 1.2 1.272 v set input leakage current max16024_tb_, set = 1.2v -20 +20 na output voltage range v out max16024_tb_, v cc > v out 1.8 5.25 v ldo = 1.2v 1.145 1.2 1.270 ldo = 1.8v 1.704 1.8 1.900 ldo = 2.5v 2.368 2.5 2.634 ldo = 3v 2.837 3 3.165 output voltage accuracy i out = 1ma ldo = 3.3v 3.114 3.3 3.482 v note 1: package thermal resistances were obtained using the method described in jedec specification jesd51-7, using a four-layer board. for detailed information on package thermal considerations, refer to www.maxim-ic.com/thermal-tutorial . downloaded from: http:///
max16023/max16024 battery-backup circuits with regulated output voltage _______________________________________________________________________________________ 3 parameter symbol conditions min typ max units line regulation v cc = (v out + 1v) to (v out + 2v), i out = 1ma 0.2 1.0 %/v load regulation v cc = v out + 1v, i out = 1ma to 2ma 0.15 1.0 % ldo = 1.2v 500 ldo = 1.8v 200 ldo = 2.5v 180 ldo = 3v 150 dropout voltage i out = 50ma (note 4) ldo = 3.3v 150 mv v cc = 1.6v 75 output current limit v cc 2v 150 ma battery freshness leakagecurrent v batt = 5.5v 10 na reset output ( reset ) reset threshold v th (see table 1) v v cc falling to reset delay t rd v cc falling at 10v/ms 20 ? reset timeout period t rp v cc rising 145 215 285 ms v out = 3.3v, i sink = 3.2ma, reset asserted 0.3 v out = 1.8v, i sink = 1ma, reset asserted 0.3 reset output low voltage v ol v out = 1.2v, i sink = 100?, reset asserted 0.3 v reset output high voltage (push-pull output) v oh v cc 1.1 x v th , i source = 100?, reset deasserted v out - 0.3v v reset output leakage current (open-drain output) v reset = 5.5v, reset deasserted 1 a power-fail comparator (pfi, pfo ) pfi input threshold v pft v pfi falling, 1.6v v cc 5.5v 0.570 0.590 0.611 v pfi input hysteresis v pfi-hys 30 mv pfi input current i pfi -1 +1 ? v out = 1.8v, i sink = 1ma, pfo asserted 0.3 pfo output low voltage v out =1.2v, i sink = 100?, pfo asserted 0.3 v pfo output high voltage (push-pull output) i source = 100?, pfo deasserted v out - 0.3v v pfo leakage current (open-drain output) v pfo = 5.5v, pfo deasserted 1 a pfo delay time (v pfi + 100mv) to (v pfi - 100mv) 20 ? manual reset ( mr ) input low voltage v il 0.3 x v cc input high voltage v ih 0.7 x v cc v pullup resistance pullup resistance to v cc 20 30 k glitch immunity 100 ns mr to reset delay 120 ns electrical characteristics (continued)(v cc = 1.53v to 5.5v, v batt = 3v, reset not asserted, t a = t j = -40? to +85?, c out = 10?, unless otherwise noted. typical val- ues are at t a = t j = +25?.) (note 2) downloaded from: http:///
max16023/max16024 battery-backup circuits with regulated output voltage 4 _______________________________________________________________________________________ electrical characteristics (continued)(v cc = 1.53v to 5.5v, v batt = 3v, reset not asserted, t a = t j = -40? to +85?, c out = 10?, unless otherwise noted. typical val- ues are at t a = t j = +25?.) (note 2) parameter symbol conditions min typ max units battery-on indicator (batt on) v out = 1.2v, i sink = 100?, batt on deasserted 0.3 v out = 1.8v, i sink = 1ma, batt on deasserted 0.3 output low voltage v ol v out = 3.3v, i sink = 3.2ma, batt on deasserted 0.3 v output high voltage(push-pull output) v oh i source = 100?, batt on asserted v out - 0.3v v output leakage current(open-drain output) v cc = 5.5v 1 a output short-circuit current sink current, v cc = 5v (note 6) 60 ma ce gating ( ce in, ce out) ce in leakage current reset asserted, v cc = 0.9 x v th or 0 -1 +1 a ce in to ce out resistance v cc = 5v, reset deasserted 8 50 ce out short-circuit current reset asserted, ce out = 0 0.75 2 ma ce in to ce out propagation delay 50 source, c load = 50pf, v cc = 4.75v 1.5 7 ns output high voltage v oh i source = 100?, reset asserted v out - 0.3v v reset to ce out delay 12 ? note 2: all devices are 100% production tested at t a = +25? and t a = +85?. limits over temperature are guaranteed by design. note 3: v batt can be 0 anytime or v cc can go down to 0 if v batt is active (except at startup). note 4: dropout voltage is defined as (v in - v out ) when v out is 2% below the value of v out when v in = v out + 1v. note 5: ce in to ce out resistance is tested with v cc = 5v and v ce in = 0 or 5v. note 6: use external current-limiting resistor to limit current to 20ma (max). downloaded from: http:///
max16023/max16024 battery-backup circuits with regulated output voltage _______________________________________________________________________________________ 5 v cc supply current vs. v cc supply voltage max16023 toc01 v cc supply voltage (v) v cc supply current ( a) 3.0 2.5 4.5 2.0 3.5 5.0 4.0 5 10 15 20 25 0 1.5 5.5 max16024ptbs25+ v out = 2.5v v th = 2.93v v cc supply current vs. temperature max16023 toc02 temperature ( c) v cc supply current ( a) 60 10 35 -15 2 4 6 8 10 1 3 5 7 90 -40 85 max16024ptbs25+ v out = 2.5v v th = 2.93v batt supply current vs. v cc supply voltage max16023 toc03 v cc supply voltage (v) batt supply current ( a) 1.0 3.0 0.5 2.5 2.0 1.5 2 4 61 3 50 0 3.5 max16024ptbs25+ v out = 2.5v v th = 2.93v v batt = 3.0v v batt = 2.8v battery supply current vs. temperature max16023 toc04 temperature ( c) battery supply current ( a) 60 10 35 -15 1 2 3 4 50 -40 85 max16024ptbs25+ v batt = +3.0v v cc = 0 batt standby current vs. temperature max16023 toc05 temperature ( c) batt standby current (na) 60 10 35 -15 -6 -2 2 6 10 -8 -4 0 4 8 -10 -40 85 v cc = 3.3v v batt = 3.0v reset output voltage low vs. sink current max16023 toc06 sink current (ma) output voltage low (v) 16 81 2 4 0.2 0.4 0.6 0.8 1.0 0 02 0 14 61 0 21 8 max16024ptbs25+ typical operating characteristics (v cc = 5v, v batt = 0, i out = 0, t a = +25?, unless otherwise noted.) table 1. reset threshold ranges table 2. fixed output voltage reset threshold ranges (v) suffix min typ max l 4.508 4.63 4.906 m 4.264 4.38 4.635 t 2.991 3.08 3.239 s 2.845 2.93 3.080 r 2.549 2.63 2.755 z 2.243 2.32 2.425 y 2.117 2.19 2.288 w 1.603 1.67 1.733 v 1.514 1.575 1.639 suffix nominal output voltage (v) 33 3.3 30 3.0 25 2.5 18 1.8 12 1.2 downloaded from: http:///
max16023/max16024 battery-backup circuits with regulated output voltage 6 _______________________________________________________________________________________ typical operating characteristics (continued) (v cc = 5v, v batt = 0, i out = 0, t a = +25?, unless otherwise noted.) v cc falling to reset delay vs. temperature max16023 toc07 temperature ( c) delay ( s) 60 10 35 -15 20 40 60 80 100 10 30 50 70 90 0 -40 85 v cc falling 10v/ms reset timeout period vs. temperature max16023 toc08 temperature ( c) reset timeout period (ms) 60 35 -15 10 185 190 195 200 210205 215 220180 -40 85 normalized reset threshold vs. temperature max16023 toc09 temperature ( c) normalized reset threshold 60 10 35 -15 0.990 1.005 1.015 1.0200.985 0.995 1.000 1.0100.980 -40 85 max16024ptbs25+ v out = 2.5v maximum transient duration vs. reset threshold overdrive reset threshold overdrive (mv) transient duration (ms) max16023 toc10 0 200 400 600 800 1000 0 25 50 75 100 125 150 175 200 reset occurs above the curve dropout voltage vs. load current max16023 toc11 load current (ma) dropout voltage (mv) 80 40 60 20 150 350 450 500100 300 50 200 250 400 0 0 100 70 30 50 10 90 max16024ptbs25+ output voltage vs. load current max16023 toc12 load current (ma) output voltage (v) 80 40 60 20 2.42 2.58 2.66 2.702.38 2.542.34 2.46 2.50 2.622.30 0 100 70 30 50 10 90 max16024ptbs25+ v out = 2.5v t a = -40 c t a = +25 c t a = +85 c downloaded from: http:///
output voltage vs. v cc voltage max16023 toc13 v cc voltage (v) output voltage (v) 14 2.1 2.5 2.7 2.82.0 2.41.9 1.8 1.7 1.6 2.2 2.3 2.61.5 06 23 5 max16024ptbs25+ i out = 0 load-transient response max16023 toc14 1ms/div outac-coupled 100mv/div 50ma i out 20ma/div 10ma max16024ptbs25+ c out = 10 f startup response max16023 toc15 2ms/div v cc 2v/divout 1v/div max16024ptbs25+i out = 0 max16023/max16024 battery-backup circuits with regulated output voltage _______________________________________________________________________________________ 7 mr falling to reset delay max16023 toc16 200ns/div mr5v/div reset5v/div chip-enable locking out signal during reset max16023 toc17 40 s/div cein2v/div ceout2v/div reset5v/div typical operating characteristics (continued) (v cc = 5v, v batt = 0, i out = 0, t a = +25?, unless otherwise noted.) downloaded from: http:///
max16023/max16024 battery-backup circuits with regulated output voltage 8 _______________________________________________________________________________________ pin description pin max16023 max16024 name function 12v cc supply voltage input. bypass v cc to gnd with a 0.1? capacitor. 2 3 batt backup battery input. if v cc falls below its reset threshold (v th ), v batt v cc , and if the regulator enters dropout, the regulator is powered from batt. if v batt < v cc , the regulator is powered from v cc . bypass batt to gnd with a 0.1? capacitor. 34 mr active-low, manual-reset input. reset asserts when mr is pulled low. reset remains low for the duration of reset timeout period after mr transitions from low to high. connect mr to out or leave unconnected if not used. mr is internally connected to v cc through a 30k pullup resistor. 4 pfi power-fail comparator input. connect pfi to a resistive divider to set the desired pfithreshold. the pfi input is referenced to an internal v pft threshold. a v pfi-hys internal hysteresis provides noise immunity. the power-fail comparator is poweredfrom out. 5 pfo active-low, power-fail comparator output. pfo goes low when v pfi falls below the internal v pft threshold and goes high when v pfi rises above v pft + v pfi-hys hysteresis. 6 7 gnd ground 78 reset active-low reset output. reset asserts when v cc falls below the reset threshold or mr is pulled low. reset remains low for the duration of the reset timeout period after v cc rises above the reset threshold and mr goes high. reset is available in push- pull and open-drain options. 8 9 out linear regulator output voltage. available in the following factory-fixed voltages of1.2v, 1.8v, 2.5v, 3.0v, or 3.3v for all devices. the max16024 is also available with an adjustable output voltage (1.8v to 5.25v). bypass out to gnd with a 10? capacitor. ? ce in chip-enable input. the input to ce gating circuitry. connect to gnd or out if notused. 5 set set output voltage input. for the fixed output voltage versions (max16024_tb_ _ _),set is not used. connect set to gnd. for max16024_tb_, connect set to an external resistive divider to set the desired output voltage between 1.8v and 5.25v. 6 batt on active-high, battery-on output. batt on goes high when in the battery backupmode. ? 0 ce out active-low, chip-enable output. ce out goes low only when ce in is low and reset is not asserted. if ce in is low when reset is asserted, ce out stays low for 12? (typ) or until ce in goes high, whichever occurs first. e p exposed pad. internally connected to gnd. connect ep to a large ground plane toaid heat dissipation. do not use ep as the only ground connection for the device. downloaded from: http:///
max16023/max16024 battery-backup circuits with regulated output voltage _______________________________________________________________________________________ 9 functional diagrams max16023 pfi pfo out gnd v cc mr reset delay logic ldo ref out reset batt dropout out downloaded from: http:///
max16023/max16024 battery-backup circuits with regulated output voltage 10 ______________________________________________________________________________________ functional diagrams (continued) max16024 cein ceout gnd v cc mr reset delay logic ldo ref v cc ce output control batt dropout out setreset batt on downloaded from: http:///
detailed description the typical applications circuit shows a typical con- nection using the max16024. out powers the sram. ifv cc is higher than the reset threshold (v th ), or if v cc is lower than v th but higher than v batt , the regulator is powered from v cc . if v cc < v th , v cc < v batt , and the regulator is in dropout, the regulator is powered frombatt (see the functional diagrams ). out supplies up to 100ma from v cc . backup-battery switchover in a brownout or power failure, it may be necessary topreserve the contents of the ram. with a backup-bat- tery installed at batt, the max16023/max16024 auto- matically switch the ram to backup power when v cc falls. the max16024 has a batt on output that goeshigh when in battery-backup mode. three conditions must be met for these devices to switch to battery backup mode: 1) v cc is lower than the reset threshold. 2) v cc is lower than v batt . 3) the regulator is in dropout (except for the 1.2v out- put version). chip-enable signal gating (max16024) the max16024 provides internal gating of ce signals toprevent erroneous data from being written to cmos ram in the event of a power failure or brownout. during normal operation, the ce gate enables and passes all ce transitions. when the reset output asserts, this path becomes disabled, preventing erroneous data from cor- rupting the cmos ram and ce out is pulled up to out through an internal current source. the 1.5ns propaga-tion delay from ce in to ce out allows the devices to be used with most ?s and high-speed dsps.during normal operation (reset not asserted), ce in is connected to ce out through a low on-resistance transmission gate. if ce in is high when a reset asserts, ce out remains high regardless of any subsequent transition on ce in during the reset event. if ce in is low when reset asserts, ce out is held low for 12? to allow completion of the read/write operation.after the 12? delay expires, ce out goes high and stays high regardless of any subsequent transitions once in during the reset event. when ce out is discon- nected from ce in, ce out is actively pulled up to out. the propagation delay through the chip-enable circuitrydepends on both the source impedance of the drive to ce in and the capacitive loading at ce out. minimize the capacitive load at ce out to minimize propagation delay, and use a low-output-impedance driver. max16023/max16024 battery-backup circuits with regulated output voltage ______________________________________________________________________________________ 11 v cc reset threshold v th cein ceout reset * t rd t rd t rp t rp if cein goes high before reset asserts, ceout goes high without delay as cein goes high. reset-to-ceout delay (12 s) * figure 1. reset and chip-enable timing downloaded from: http:///
max16023/max16024 manual-reset input (max16023/max16024) many ?-based products require manual-reset capabili-ty, allowing the operator, a test technician, or external logic circuitry to initiate a reset. for the max16023/ max16024, a logic-low on mr asserts reset . reset remains asserted while mr is low. when mr goes high, reset deasserts after a minimum of 145ms (t rp ). mr has an internal 30k pullup resistor to v cc . mr can be driven with ttl/cmos logic levels or with open-drain/collector outputs. connect a normally open momentary switch from mr to gnd to create a manual- reset function; external debounce circuitry is notrequired. if mr is driven from a long cable or the device is used in a noisy environment, connect a 0.1? capaci-tor from mr to gnd to provide additional noise immunity. battery-on indicator (max16024) the max16024? batt on output goes high when inbattery-backup mode. use batt on to indicate bat- tery-switchover status. battery freshness seal the max16023/max16024 battery freshness seal dis-connects the backup battery from internal circuitry and out until v cc is applied. this ensures the backup bat- tery connected to batt is fresh when the final productis used for the first time. the internal freshness seal latch prevents batt from powering out until v cc has come up for the first time, setting the latch. when v cc subsequently turns off, batt begins to power out.to reenable the freshness seal (max16023/ max16024): 1) connect a battery to batt. 2) bring v cc to 0. 3) drive mr higher than v batt + 1.2v for at least 3?. 4) pull out to 0. reset output (max16023/max16024) a ?? reset input starts the ? in a known state. themax16023/max16024 ? supervisory circuits assert a reset to prevent code-execution errors during power- up, power-down, and brownout conditions. reset asserts when v cc is below the reset threshold and remains low for at least 145ms (t rp ) after v cc rises above the reset threshold. reset also asserts when mr is low. reset is available in both push-pull and open-drain configurations. power-fail comparator (max16023) the max16023 offers an additional undervoltage com-parator. the output pfo goes low when the voltage at pfi falls below its v pft threshold. common uses for the power-fail comparator include monitoring the input of thepower supply (such as a battery) before any voltage reg- ulation to provide an early power-fail warning, so soft- ware can conduct an orderly system shutdown. the power-fail comparator has a typical input hysteresis of v pfi-hys and is powered from out, making it indepen- dent of the reset circuit. connect pfi to gnd, if not used. regulator output fixed output voltages of 1.2v, 1.8v, 2.5v, 3.0v, and3.3v are available for all devices. the regulator output delivers up to 100ma of load current. the max16024 is available with both fixed and adjustable output-voltage options. use an external resistive divider network connected between out, set, and gnd (figure 2) to set the adjustable output voltage from 1.8v to 5.25v. connect set to gnd for parts with fixed output voltage option. battery-backup circuits with regulated output voltage 12 ______________________________________________________________________________________ max16024 0.1 f 1.53 to 5.5v gnd v cc reset to p r1 r2 set 10 f 1.8v to 5.25v v out = v set (1 + r1/r2) v set = 1.2v out figure 2. setting the adjustable output voltage (max16024 only) downloaded from: http:///
applications information the max16023/max16024 are protected for typicalshort-circuit conditions of 10s or less. shorting out to ground for longer than 10s might damage the device. bypass v cc and batt to gnd with a 0.1? capacitor each. connect a 10? low-esr capacitor from out tognd. all capacitors should be mounted as close as possible to the device. monitoring an additional supply the max16023 power-fail comparator can monitoreither positive or negative supplies using a resistive divider to pfi (figures 3 and 4). pfo can be used to generate an interrupt to the ? or to trigger a reset. tomonitor a negative supply, connect the top of the resis- tive divider to v cc . connect the bottom of the resistive divider to the negative voltage to be monitored. adding hysteresis to pfi the power-fail comparators have a typical input hys-teresis of v pfi-hys . this is sufficient for most applica- tions where a power-supply line is being monitoredthrough an external voltage-divider (see the monitoring an additional supply section). figure 5 shows how to add hysteresis to the power-fail comparator. select theratio of r1 and r2 such that pfi sees v pft when v in falls to the desired trip point (v trip ). resistor r3 adds hysteresis. r3 is typically an order of magnitude greaterthan r1 or r2. the current through r1 and r2 should be at least 100? to ensure that the 1? (max) pfi input current does not shift the trip point. r3 should be larger than 50k to prevent it from loading down pfo . capacitor c1 adds additional noise rejection. max16023/max16024 battery-backup circuits with regulated output voltage ______________________________________________________________________________________ 13 max16023l 0.1 f gnd pfi r2 r1 mr pfo additional supply reset voltage reset v 2 v cc v 1 reset p v 2(reset) = v pft x ( ) r1 + r2 r2 figure 3. monitoring an additional supply by connecting pfo to mr max16023 0.1 f gnd pfi r2 r1 pfo v cc v trip = v pft - ( 5 - v pft ) r2r1 v trip is negative v- 5v pfo 0 +5v v trip v- 0 figure 4. monitoring a negative supply downloaded from: http:///
max16023/max16024 operation without a backup power source the max16023/max16024 provide battery-backupfunctions. if a backup power source is not used, con- nect batt to gnd. replacing the backup battery when v cc is above v th , the backup power source can be removed without danger of triggering a reset pulse.the device does not enter battery-backup mode when v cc stays above the reset threshold voltage. negative-going v cc transients the max16023/max16024 are relatively immune toshort duration, negative-going v cc transients. resetting the ? when v cc experiences only small glitches is usually not desirable. a 0.1? bypasscapacitor mounted close to the v cc pin provides addi- tional transient immunity. capacitor selection and regulator stability for stable operation, connect a low-esr 10? (min) out-put capacitor from out to gnd. to reduce noise and improve load-transient response and power-supply rejec- tion, use larger output capacitor values. battery-backup circuits with regulated output voltage 14 ______________________________________________________________________________________ max16023 0.1 f gnd pfi pfo r2 r1 r3 v cc v h = ( v pft + v pfi - hys ) x ( + + 1 ) r1r2 r1r3 v l = r1 x ( - ) + v pft v pft r2 v cc - v pft r3 where v pft is the power-fail threshold voltage. *optional +5v v in c1* to p pfo 0 +5v v trip v l v h v in v trip = v pft x ( ) r1 + r2 r2 figure 5. adding hysteresis to the power-fail comparator part number table part output type r eset t h r esh o l d vo l t a g e ( v) regul ated ou tpu t vo lta ge ( v) part output type r eset t h r esh o l d vo l t a g e ( v) r eg u l a t ed o u t pu t vo l t a g e ( v) max16023ltal12+t push-pull 4.63 1.2 max16024ltbl12+t push-pull 4.63 1.2 max16023ltal18+t push-pull 4.63 1.8 max16024ltbl18+t push-pull 4.63 1.8 max16023ltal25+t push-pull 4.63 2.5 max16024ltbl25+t push-pull 4.63 2.5 max16023ltal33+t push-pull 4.63 3.3 max16024ltbl33+t push-pull 4.63 3.3 max16023ltam12+t push-pull 4.38 1.2 max16024ltbm12+t push-pull 4.38 1.2 max16023ltam18+t push-pull 4.38 1.8 max16024ltbm18+t push-pull 4.38 1.8 max16023ltam25+t push-pull 4.38 2.5 max16024ltbm25+t push-pull 4.38 2.5 max16023ltam33+t push-pull 4.38 3.3 max16024ltbm33+t push-pull 4.38 3.3 max16023ltat12+t push-pull 3.08 1.2 max16024ltbt12+t push-pull 3.08 1.2 max16023ltat18+t push-pull 3.08 1.8 max16024ltbt18+t push-pull 3.08 1.8 max16023ltat25+t push-pull 3.08 2.5 max16024ltbt25+t push-pull 3.08 2.5 max16023ltas12+t push-pull 2.93 1.2 MAX16024LTBS12+t push-pull 2.93 1.2 max16023ltas18+t push-pull 2.93 1.8 MAX16024LTBS18+t push-pull 2.93 1.8 max16023ltas25+t push-pull 2.93 2.5 MAX16024LTBS25+t push-pull 2.93 2.5 max16023ltar12+t push-pull 2.63 1.2 max16024ltbr12+t push-pull 2.63 1.2 max16023ltar18+t push-pull 2.63 1.8 max16024ltbr18+t push-pull 2.63 1.8 max16023ltar25+t push-pull 2.63 2.5 max16024ltbr25+t push-pull 2.63 2.5 max16023ltaz12+t push-pull 2.32 1.2 max16024ltbz12+t push-pull 2.32 1.2 downloaded from: http:///
max16023/max16024 battery-backup circuits with regulated output voltage ______________________________________________________________________________________ 15 part number table (continued) part output type r eset t h r esh o l d vo l t a g e ( v) regul ated ou tpu t vo lta ge ( v) part output type r eset t h r esh o l d vo l t a g e ( v) r eg u l a t ed o u t pu t vo l t a g e ( v) max16023ltaz18+t push-pull 2.32 1.8 max16024ltbz18+t push-pull 2.32 1.8 max16023ltay12+t push-pull 2.19 1.2 max16024ltby12+t push-pull 2.19 1.2 max16023ltay18+t push-pull 2.19 1.8 max16024ltby18+t push-pull 2.19 1.8 max16023ltaw12+t push-pull 1.67 1.2 max16024ltbw12+t push-pull 1.67 1.2 max16023ltav12+t push-pull 1.575 1.2 max16024ltbv12+t push-pull 1.575 1.2 max16023ptal12+t open-drain 4.63 1.2 max16024ptbl12+t open-drain 4.63 1.2 max16023ptal18+t open-drain 4.63 1.8 max16024ptbl18+t open-drain 4.63 1.8 max16023ptal25+t open-drain 4.63 2.5 max16024ptbl25+t open-drain 4.63 2.5 max16023ptal33+t open-drain 4.63 3.3 max16024ptbl33+t open-drain 4.63 3.3 max16023ptam12+t open-drain 4.38 1.2 max16024ptbm12+t open-drain 4.38 1.2 max16023ptam18+t open-drain 4.38 1.8 max16024ptbm18+t open-drain 4.38 1.8 max16023ptam25+t open-drain 4.38 2.5 max16024ptbm25+t open-drain 4.38 2.5 max16023ptam33+t open-drain 4.38 3.3 max16024ptbm33+t open-drain 4.38 3.3 max16023ptat12+t open-drain 3.08 1.2 max16024ptbs12+t open-drain 3.08 1.2 max16023ptat18+t open-drain 3.08 1.8 max16024ptbs18+t open-drain 3.08 1.8 max16023ptat25+t open-drain 3.08 2.5 max16024ptbs25+t o p e n - d r a i n 3.08 2.5 max16023ptas12+t open-drain 2.93 1.2 max16024ptbt12+t open-drain 2.93 1.2 max16023ptas18+t open-drain 2.93 1.8 max16024ptbt18+t open-drain 2.93 1.8 max16023ptas25+t open-drain 2.93 2.5 max16024ptbt25+t open-drain 2.93 2.5 max16023ptar12+t open-drain 2.63 1.2 max16024ptbr12+t open-drain 2.63 1.2 max16023ptar18+t open-drain 2.63 1.8 max16024ptbr18+t open-drain 2.63 1.8 max16023ptar25+t open-drain 2.63 2.5 max16024ptbr25+t open-drain 2.63 2.5 max16023ptaz12+t open-drain 2.32 1.2 max16024ptbz12+t open-drain 2.32 1.2 max16023ptaz18+t open-drain 2.32 1.8 max16024ptbz18+t open-drain 2.32 1.8 max16023ptay12+t open-drain 2.19 1.2 max16024ptby12+t open-drain 2.19 1.2 max16023ptay18+t open-drain 2.19 1.8 max16024ptby18+t open-drain 2.19 1.8 max16023ptaw12+t open-drain 1.67 1.2 max16024ptbw12+t open-drain 1.67 1.2 max16023ptav12+t open-drain 1.575 1.2 max16024ptbv12+t open-drain 1.575 1.2 max16024ptbl+t open-drain 4.63 adjustable max16024ltbl+t push-pull 4.63 adjustable max16024ptbm+t open-drain 4.38 adjustable max16024ltbm+t push-pull 4.38 adjustable max16024ptbt+t open-drain 3.08 adjustable max16024ltbt+t push-pull 3.08 adjustable max16024ptbs+t open-drain 2.93 adjustable MAX16024LTBS+t push-pull 2.93 adjustable max16024ptbr+t open-drain 2.63 adjustable max16024ltbr+t push-pull 2.63 adjustable max16024ptbz+t open-drain 2.32 adjustable max16024ltbz+t push-pull 2.32 adjustable max16024ptby+t open-drain 2.19 adjustable max16024ltby+t push-pull 2.19 adjustable max16024ptbw+t open-drain 1.67 adjustable max16024ltbw+t push-pull 1.67 adjustable max16024ptbv+t open-drain 1.575 adjustable max16024ltbv+t push-pull 1.575 adjustable bold parts denote standard versions. samples are generally available on standard versions. contact factory for availability of nonstandard versions. downloaded from: http:///
max16023/max16024 battery-backup circuits with regulated output voltage 16 ______________________________________________________________________________________ typical applications circuit max16024l 0.1 f 3v 0.1 f 0.1 f 10 f batt gnd set pushbutton cein ceout batt on out reset address decode rtc ram v cc ce mr p rst a0?a15 3.3v v cc part outputs ( reset , pfo , batt on ) reset mr power-fail comparator ce gate batt on regulator output voltage max16023l push-pull ? fixed max16023p open drain ? fixed max16024l push-pull ? ? fixed/adjustable max16024p open drain ? ? fixed/adjustable selector guide downloaded from: http:///
max16023/max16024 battery-backup circuits with regulated output voltage maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a maxim product. no circuit 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 ____________________ 17 2008 maxim integrated products is a registered trademark of maxim integrated products, inc. package information for the latest package outline information and land patterns, goto www.maxim-ic.com/packages . package type package code document no. 8 tdfn t833-2 21-0137 10 tdfn t1033-1 21-0137 chip information process: bicmos downloaded from: http:///

▲Up To Search▲

Price & Availability of MAX16024LTBS

	To Download MAX16024LTBS Datasheet File
If you can't view the Datasheet, Please click here to try to view without PDF Reader .