MAX6427MAX6438 19-2323 Rev 2 12/05 Low-Power, Single/Dual-Level Battery Monitors with Hysteresis General Description Features The MAX6427MAX6438 are single/dual-level battery mon- Factory-Trimmed or User-Adjustable Threshold itors with internal hysteresis. These devices are offered with Options single (MAX6427/MAX6428/MAX6429, MAX6433/ Factory-Trimmed Low Thresholds from 1.6V to MAX6434/MAX6435) or dual (MAX6430/MAX6431/ 2.1V or 2.6V to 3.1V in 100mV Increments MAX6432, MAX6436/MAX6437/MAX6438) low-battery out- (MAX6427MAX6432) put indicators, which can be used to indicate three battery Factory-Trimmed High Thresholds from 2.3V to conditions: battery is good (operate system in normal 2.6V or 3.3V to 3.6V in 100mV Increments mode), battery is weak (operate system in low-power (MAX6427MAX6432) mode), or battery is empty (disable the system). User-Adjustable Low/High Thresholds with These devices are ideal for monitoring single lithium-ion 615mV Internal Reference (MAX6433MAX6438) (Li+) cells or multicell alkaline/NiCd/NiMH power supplies. Low Current (1A, typ) When the power-supply voltage drops below the specified Single or Dual Low-Battery Outputs low threshold, the low-battery output asserts. When the Push-Pull LBO, Open-Drain LBO, and Open-Drain voltage rises above the specified high threshold, the low- LBO Options battery output is deasserted following a 140ms minimum timeout period. The timeout period ensures that the supply 140ms Minimum LBO Timeout Period voltages have stabilized before power-converter or micro- Immune to Short Battery Voltage Transients processor activity is enabled. Guaranteed Valid LBO Logic State to BATT = 1.0V The MAX6427MAX6438 family is available with several -40C to +85C Operating Temperature Range monitoring options. The MAX6427/MAX6428/MAX6429 Small 3, 4, 5 and 6-Pin SOT Packages offer factory-trimmed battery-monitor thresholds, with a sin- No External Components Required gle low-battery output. The MAX6430/MAX6431/MAX6432 (MAX6427MAX6432) also feature factory-trimmed thresholds, but have two low- Ordering Information battery outputs. The MAX6433MAX6438 have user-adjustable threshold PART TEMP RANGE PIN-PACKAGE voltages permitting the user to select the hysteresis range, MAX6427 UR-T -40C to +85C 3 SOT23-3 and consequently the sensitivity of the system to noise. A Ordering Information continued at end of data sheet. wide hysteresis range also prevents chattering that can The MAX6427MAX6432 are available with factory-trimmed result due to battery recovery after load removal. Single battery-monitor thresholds. Select the desired thresholds low-battery outputs are supplied by the MAX6433/ using Tables 1 or 2 and enter the corresponding letters in MAX6434/MAX6435 and dual low-battery outputs by the the part number by replacing . MAX6436/MAX6437/MAX6438. Devices are available in both leaded and lead-free packaging. The MAX6427MAX6438 family is available with three out- Specify lead-free by replacing -T with +T when ordering. put logic options for convenient interface with system Note: There are 26 standard versions with a required order power circuitry or microprocessors. The family is offered in minimum of 2500 pieces. Sample stock is generally held on small SOT23 and SOT143 packages and is fully specified the standard versions only (see Standard Versions Table). Required order increment is 10,000 pieces for nonstandard over temperature. versions. Contact factory for availability. All devices avail- Applications able in tape-and-reel only. Pin Configurations Battery-Powered Systems (Single-Cell Li+ or Two/Three-Cell NiMH, NiCd, Alkaline) TOP VIEW Cell Phones/Cordless Phones Pagers LBO 1 Portable Medical Devices PDAs (LBO) MAX6427 3 GND Electronic Toys MP3 Players MAX6428 MAX6429 BATT 2 SOT23-3 ( ) ARE FOR THE MAX6429. Typical Operating Circuit appears at end of data sheet. Pin Configurations continued at end of data sheet. Maxim Integrated Products 1 For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct at 1-888-629-4642, or visit Maxims website at www.maxim-ic.com.Low-Power, Single/Dual-Level Battery Monitors with Hysteresis ABSOLUTE MAXIMUM RATINGS BATT, V to GND ................................................-0.3V to +6.0V Continuous Power Dissipation (T = +70C) DD A HTHIN, LTHIN Inputs to GND.....................-0.3V to (V + 0.3V) 3-Pin SOT23-3 (derate 4.0mW/C above +70C) .......320mW DD Open-Drain LBO/LBO, LBOH/LBOH, 4-Pin SOT143-4 (derate 4.0mW/C above +70C) .....320mW LBOL/LBOL to GND .........................................-0.3V to +6.0V 5-Pin SOT23-5 (derate 7.1mW/C above +70C) .......571mW Push-Pull LBO/LBO, LBOH/LBOH, 6-Pin SOT23-6 (derate 8.7mW/C above +70C) .......696mW LBOL/LBOL to GND ................-0.3V to (BATT or V + 0.3V) Operating Temperature Range ...........................-40C to +85C DD Input Current (all pins) ........................................................20mA Junction Temperature......................................................+150C Output Current (all pins) .....................................................20mA Storage Temperature Range .............................-65C to +150C Lead Temperature (soldering, 10s) .................................+300C 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 absolute maximum rating conditions for extended periods may affect device reliability. ELECTRICAL CHARACTERISTICS (BATT = 1.0V to 5.5V or V = 1.6V to 5.5V, T = -40C to +85C, unless otherwise specified. Typical values are at T = +25C.) DD A A (Note 1) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS 1.2 5.5 T = -40C to +85C A Operating Voltage Range V V BATT 1.0 5.5 T = 0C to +70C A Operating Voltage Range V T = -40C to +85C 1.6 5.5 V DD A BATT Supply Current I V = 3.7V, no load (MAX6427MAX6432) 1 1.5 A BATT BATT V = 3.7V, no load DD V Supply Current I 1 1.5 A DD DD (MAX6433MAX6438) FACTORY-FIXED THRESHOLDS (MAX6427MAX6432) Factory-fixed options, BATT rising, HTH Threshold V LBO deasserted when BATT rises above -2.5 +2.5 % HTH (Note 2) V (MAX6427/MAX6428/MAX6429) HTH Factory-fixed options, BATT falling, LTH Threshold V LBO asserted when BATT falls below V -2.5 +2.5 % LTH LTH (Note 2) (MAX6427/MAX6428/MAX6429) Factory-fixed options, BATT falling, LBOH HTH- Threshold asserted when BATT falls below V V -2.5 +2.5 % HTH- HTH- (Note 2) (MAX6430/MAX6431/MAX6432) Factory-fixed options, BATT rising, HTH+ Threshold V LBOH deasserted when BATT rises above -2.5 +2.5 % HTH+ (Note 3) V (MAX6430/MAX6431/MAX6432) HTH+ Factory-fixed options, BATT falling, LTH- Threshold V LBOL asserted when BATT falls below V -2.5 +2.5 % LTH- LTH- (Note 2) (MAX6430/MAX6431/MAX6432) Factory-fixed options, BATT rising, LTH+ Threshold V LBOL deasserted when BATT rises above -2.5 +2.5 % LTH+ (Note 3) V (MAX6430/MAX6431/MAX6432) LTH+ 2 MAX6427MAX6438