pt7 m7433/34/35 |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||| |||||| ||||||||||| ? p supervisory circuit 12 - 07 - 0002 pt0213 - 4 0 7 / 0 5 /12 1 features ? user - adjustable low/high thresholds with 615mv internal reference ? low current ( 1.5 a typ) ? single low - battery outputs ? push - pull lbo, open - drain lbo and open - drain lbo options ? 90ms minimum lbo timeout period ? immune to short battery voltage tran sients ? - 40c to + 85c operating temperature range application ? monitoring lithiumion (li+) cells or multicell alkaline/ nicd/ nimh power supplies. description the pt7m7433/34 /35 are single - level battery monitors with internal hysteresis. these devices are offered with single low - battery output indicators which can be used to indicate three battery conditions: good (operate system in normal mode), weak (operate system in low - power mode), or empty (disable the system). the pt7m7 433/34 /35 are user - adjust able threshold voltages permitting the user to select the hysteresis range and consequently the sensitivity of the system to noise. a wide hysteresis range also prevents chattering that can result due to battery recovery after load removal. pin configu ration pin description pin name type description 1 hthin i hth threshold monitor input. a resistor - divider network sets the high threshold associated with lbo/lbo. 2 gnd p ground 3 lthin i lth threshold monitor input. a resistor - divider network sets the low threshold associated with lbo/lbo. 4 lbo/lbo o low - battery output. lbo /lbo is asserted when lthin drops below v lthin , and remains asserted for at least 90ms hthin rises above v hthin . push - pull output for pt7m7433. open drain output for pt7m7434/35. 5 vcc p supply voltage. device power supply for adjustable threshold versions. 4 3 1 2 lbol gnd batt 2 1 4 5 6 5 4 1 2 3 1 2 lbo gnd batt 3 lthin gnd lbo 3 1 2 3 hthin gnd lthin lbol 4 5 6 1 2 3 sot23-3 pt7m7427xx pt7m7428xx pt7m7429xx pt7m7430xx pt7m7431xx sot23-5 pt7m7433 pt7m7434 sot23-6 pt7m7436 lboh vcc pt7m7437 pt7m7438 4 3 1 2 lboh lbol gnd pt7m7432xx vcc lbo batt gnd lboh hthin hthin gnd lthin lbol lboh vcc 5 nc 5 nc batt 4 5 6 1 2 3 pt7m3806m pt7m3806e gnd hsense lsense vcc rstsense reset 3 1 2 4 5 pt7m7435 lthin gnd lbo vcc hthin 3 1 2 4 5 pt7m7479h pt7m7479l lth gnd vdd rst (/rst) hth
||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||| ||||||||||||||||||||||||||||||||||||||||| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||| |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||| 12 - 07 - 0002 pt0213 - 4 0 7 / 0 5 /12 2 pt7 m74 33/34/35 ? p supervisory circuit block diagram maximum ratings storage temperature .............................................. .............. - 65 o c to +150 o c ambient temperature with power applied.......................... - 40 o c to +85 o c supply voltage to ground potential (vcc to gnd) .............. - 0.3v to +7.0v dc input voltage (all inputs except vcc and gnd)...... - 0.3v to vcc+0. 3v dc output current (all outputs) ..........................................................20ma power dissipation .............................................................................. 320mw (depend on package) pt7m7433/34/35block diagr am 615 mv vcc lthi n hthin r1 r2 r3 vcc vcc r q q s lbo timout period lbo (lbo) external resistor - driver lbo: pt7m7433/34 lbo: pt7m7435 note: stresses greater than those listed under maximum ratings may cause permanent damage to the device. this is a stress rating only and functional operation of the device at these or any other condi - tions above those indicated in the operational sec - tions of this specification is not implied. exposure to absolute maximum rating conditions for extended periods may affect reliability.
||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||| ||||||||||||||||||||||||||||||||||||||||| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||| |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||| 12 - 07 - 0002 pt0213 - 4 0 7 / 0 5 /12 3 pt7 m74 33/34/35 ? p supervisory circuit dc electrical char acteristics (v cc =1.8v to 5.5v, t a = - 40~85oc, unless otherwise noted. typical values are at t a = +25oc) description symbol test conditions min typ max unit operating voltage range v cc t a = - 40~85oc 1.8 - 5.5 v v cc supply current i cc v cc = 3.7v, no load t a = - 40~85oc - 1.5 2 .5 a oh v cc 1.6v, i source = 200a cc 2.7v, i source = 500a cc 4.5v, i source = 800a ol v cc 1.6v, i sink = 100a cc 2.7v, i sink = 1.2ma - - 0.3 v cc 4.5v, i sink = 3.2ma - - 0.4 open - drain output leakage current i lkg - - - 1 a lkg v hthin or v lthin > 400mv - - 20 na user - adjustable thresholds (pt7m7433/34/35) hthin threshold( note ) v hthin hthin ris ing, lbo is deasserted when hthin rises above 615mv. t a = 25oc - 1.5 - + 1.5 % t a = - 3 0~ 70 oc - 2.5 - - 2.5 % lthin threshold( note ) v lthin lthin falling, lbo is asserted when lthin falls below 615mv. t a = 25oc - 1.5 - + 1.5 % t a = - 3 0~ 70 oc - 2.5 - - 2.5 % note: typical value is 615mv. minimum and maximum value is percentage of typical value. ac electrical characteristics fig 1 . pt7m7433/34/35 timing diagram (v cc =1.8v to 5.5v, t a = - 40~85oc, unless otherwise noted. typical values are at t a = +25oc) symbol description test conditions min typ max unit t lbop timeout period - 90 200 350 ms t lbod delay - - 70 - ? v cc t lbop lbo (pt7m7433/34) t lbop lbo (pt7m7435) v hth v lth t lbod t lbod
||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||| ||||||||||||||||||||||||||||||||||||||||| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||| |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||| 12 - 07 - 0002 pt0213 - 4 0 7 / 0 5 /12 4 pt7 m74 33/34/35 ? p supervisory circuit function description the pt7m7433/34 /35 are available with user adjustable monitoring. the user sets the thr eshold voltages for the pt7m7433/34 /35 , which permit the user to select the hysteresis range, and consequently the sensitivity of the system to noise. a wide hysteresis range prevents chattering that can result during batte ry recovery or load removal. the p t7m7433/ 34 / 35 have single low - battery outputs. the pt7m7433/34 /35 combine a 615mv reference with two comparators, logic, and timing circuitry to provide the user with information about the charge state of the power - supply batteries. the pt7m7433/34 /35 mo nitor separate high - voltage and low - voltage thresholds to determine battery status. the output can be used to signal when the battery is charged, when the batter y is low, and when the battery is empty. pt7m7433/34 /35 are also available with thresholds dete rmined using an external resistor - divider (see application information resistor - value selectio n). the adjustable versions can monitor down to 0.62v, making them suitable for monitoring single - cell alkaline, nimh, and nicd applications (v cc 1.8v). when th e power - supply voltage drops below the specified low threshold, the low - battery output asserts (see low - battery outpu t). when the voltage rises above the specified high threshold following a 90ms (min) time - out period, the low - battery output is deasserted (see threshold monitorin g). this ensures the supply voltage has stabilized before power - converter or microprocessor activity is enabled. low - battery output the low - battery outputs are available in active - low (lbo, push - pull and open - drain) and action - hi gh (lbo open - drain) configurations. push - pull outputs are referenced to v cc (for adjustable threshold versions). the open - drain devices can be pulled to a voltage independent of v cc or batt, up to 5.5v. this allows the device to monitor and operate from d irect battery voltage while interfacing to higher voltage microprocessors. the pt7m7433/34 /35 single - output voltage monitors provide a single low - battery output, lbo /lbo . the pt7m7433/34 adjustable - threshold parts assert lbo /lbo when the lthin input drops below the v lthin threshold (615mv). threshold monitoring the pt7m7433/34 /35 hthin and lthin inputs are high - impedance inputs to comparators. an external resistor divider network is required between the monitored voltage, hthin, lthin, and gnd to select the desired thresholds (see application information resistor - value selectio n). the pt7m7433/34 /35 single - output voltage monitors assert lbo /lbo when lthin drops below the internal lthin reference (615mv). lbo /lbo is deasserted when hthin rises above the i nternal hthin reference level (615mv) for at least 90ms (see ac electrical characteristics: fig 1 ). hysteresis hysteresis increases the comparators noise margin by increasing the upper threshold or decreasing the lower threshold (see b low). the hystere sis prevents the output from oscillating (chattering) when v cc is near the low - battery threshold. this is especially important for applications where the load on the battery creates significant fluctuations in battery voltages. adjustable hysteresis (pt7m 7433/34 /35 ) block diagram shows the correct connections for the external resistor - dividers. to adjust the low - battery threshold and hysteresis connect resistor r1 between v cc and lthin, resistor r2 between lthin and hthin, and r3 between hthin and gnd. th e hysteresis for the pt7m7433/34 /35 is determined by an external resistor - divider network (see application information resistor - value selectio n).
||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||| ||||||||||||||||||||||||||||||||||||||||| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||| |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||| 12 - 07 - 0002 pt0213 - 4 0 7 / 0 5 /12 5 pt7 m74 33/34/35 ? p supervisory circuit application information resistor - value selection (programming the adjustable thres holds) v ref = v lthin = v hthin = 615mv v triplow = v lth = v ref ( ) v triphigh = v htl = v ref ( ) r total = r1 + r2 + r3 use the following steps to determine values for r1, r2, and r3 of fun ctional block diagram. 1) choose a value for r total . because the pt7m7433/34 /35 have very high input impedance, r total can be up to 5m. 2) calculate r3 based on r total and the desired upper trip point: r3 = = 3) calculate r2 based on r total , r3, and the desired lower trip point: r2 = - r3 4) calculate r1 based on rtotal, r3, and r2: r1 = r total C r2 C r3 v batt v hth v lth v hyst t lbcp lbo hth C battery voltage good enable operation lth C battery voltage low suspend/disable operation r1 + r2 + r3 r2 + r3 r1 + r2 + r3 r3 v ref r total v triphigh 615mv r total v triphigh 615mv r total v triplow fig 2 . pt7m7433/34 /35 adjustable hysteresis
||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||| ||||||||||||||||||||||||||||||||||||||||| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||| |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||| 12 - 07 - 0002 pt0213 - 4 0 7 / 0 5 /12 6 pt7 m74 33/34/35 ? p supervisory circuit mechanical information tae (lead free and green sot23 - 5) symbol min max a 1.05 1.25 a1 0.00 0.10 a2 1.05 1.15 b 0.30 0.50 c 0.10 0.20 d 2.82 3.02 e 1.50 1.70 e1 2.65 2.95 e e1 1.80 2.00 l 0.30 0.60 0 8 pkg. dimensions(mm) 0.95bsc note: 1 ) controlling dimensions in millimeters. 2 ) ref : jedec mo - 178 c/aa
||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||| ||||||||||||||||||||||||||||||||||||||||| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||| |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||| 12 - 07 - 0002 pt0213 - 4 0 7 / 0 5 /12 7 pt7 m74 33/34/35 ? p supervisory circuit ordering information part number package code package marking code pt7m7433tae ta lead - free and green sot23 - 5 mm pt 7m7434tae ta lead - free and green sot23 - 5 mn PT7M7435TAE ta lead - free and green sot23 - 5 mo note: ? e = pb - free and green ? adding x suffix = tape /r eel table 1. function comparison of pt7m7 433/34 /35 item part no. output threshold open - drain push - pull sing le dual factory fixed user adjustable active high active low active low 1 pt7m7433 - - ? ? ? ? ? ? ? ? ? sot - 23 package top marking instruction sample: mmpj part no.: pt7m7433 date code: year 2005 ww10 lead free and green package 1. package type: sot - 23 2. package code: t a 3. 2005 - year code: p 4. work week code: ww7 - g ww8 - h ww9 - i ww10 - j ww11 - k ww12 - l ww13 - m ww14 - n ww15 - o ww16 - p ww17 - q 5. font style: helvetica or arial 6. max characters per line (only 1 line): 4 7. max characters height: 0.8 mm 8. min characters height: 0.6 mm 9. max characters width: 0.6 mm 10. mark placement: center pericom semiconductor corporation ? 1 - 800 - 435 - 2336 ? www.pericom.com pericom reserves the right to make changes to its products or specifications at any time, without notice, in order to improve design or performance and to supply the best possible product. pericom does not assume any responsibility for use of any circuitry described other than the circu itry embodied in pericom product. the company makes no representations that circuitry described herein is free from patent infringement or other rights, of pericom . mm pj part no. 2 bit code (see table1) date code year & work week lead - free sign - : lead - free and green
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