DS2741 19-4683 Rev 1 7/09 Current Monitor and Accumulator with Integrated Sense Resistor General Description Features The DS2741 current monitor/accumulator is a complete Complete, Low-Cost, Integrated Current-Sensing current-sensing, measuring, and accumulation device and Accumulation Solution with Serial Digital tailored for cost-sensitive, battery-powered applications Output in a small 3mm x 3mm TDFN package. As a result, the On-Board 38m Sense Resistor DS2741 is a key component in battery-charge control and remaining capacity-estimation applications. Current Measurement: 2 Through its I C interface, the DS2741 gives the host Signed 10-Bit Bidirectional Measurement system access to current measurement and accumula- 2.5A Dynamic Range tion registers. The 7-bit slave address is factory pro- 1% Error at +25C grammable, allowing up to 128 devices to be individually 2% Error Over Temperature addressed by the host system. Current Accumulation: 0.247mAhr LSB Applications 8.1Ahrs Full-Scale Range Cell Phones 2 Industry-Standard I C Interface with Factory- PDAs Programmable Slave Address Battery Monitor/Rechargers 2.5V to 4.5V Single-Supply Operation Low-Power Consumption: Ordering Information Active Current: 60A (typ) PART TEMP RANGE PIN-PACKAGE Sleep Current: 1A (typ) DS2741N+ -20C to +70C 14 TDFN-EP* -20C to +70C Operating Range DS2741N+T -20C to +70C 14 TDFN-EP* 14-Pin TDFN (3mm x 3mm x 0.8mm) +Denotes a lead(Pb)-free/RoHS-compliant package. T = Tape and reel. *EP = Exposed pad. Typical Operating Circuit Pin Configuration TOP VIEW RS- RS- RS- RS- SLP GND DNC 14 13 12 11 10 9 8 CHARGER/ RS+ RS- LOAD DC-DC Li + DS2741 CONVERTER BATTERY V CC 1.8V DS2741 SLP 2.2k 2.2k EP* 0.1F SDA MICROPROCESSOR GND SCL 1243 5 6 7 RS+ RS+ RS+ RS+ SDA SCL V CC TDFN *EXPOSED PAD Maxim Integrated Products 1 For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxims website at www.maxim-ic.com. +Current Monitor and Accumulator with Integrated Sense Resistor ABSOLUTE MAXIMUM RATINGS Voltage Range on V Relative to GND ...............-0.5V to +6.0V Pulsed Internal Sense Resistor CC Voltage Range on SDA, SCL, Current ..................................10A for <100s/s, <1000 pulses RS+, RS-, SLP Relative to GND.....-0.5V to (V + 0.5V), not to Operating Temperature Range ...........................-20C to +70C CC exceed +6.0V Storage Temperature Range .............................-55C to +125C Soldering Temperature...........................Refer to the IPC/JEDEC Continuous Internal Sense Resistor Current ......................2.7A J-STD-020 Specification. 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. RECOMMENDED OPERATING CONDITIONS (T = -20C to +70C.) A PARAMETER SYMBOL CONDITIONS MINTYP MAX UNITS Supply Voltage V (Note 1) 2.5 4.5 V CC Input Logic-High: SCL, SDA V 1.5 V IH Input Logic-Low: SCL, SDA V 0.4 V IL 0.7 x Input Logic-High: SLP V V IH V CC 0.3 x Input Logic-Low: SLP V V IL V CC Power-Up Ramp Time from t 25 ms RAMP 0V to V CCMIN DC ELECTRICAL CHARACTERISTICS (2.5V V 4.5V, T = -20C to +70C.) CC A PARAMETER SYMBOL CONDITIONS MINTYP MAX UNITS Active Current I SLP = SCL = SDA = V 60 90 A ACTIVE CC Sleep-Mode Current I SLP = 0V 1 2 A SLEEP Output Logic-Low: SDA V I = 4mA (Note 1) 0.4 V OL OL Internal Current-Sense Resistor R +25C 38 45 m SNS Value Current Resolution I 2.64 mA LSB Current Full-Scale Magnitude I (Note 2) 2.54 2.7 A FS Current-Sense Accuracy at +25C A I at 1.5A 1 3 % TL SENSE Current-Sense Accuracy from A I at 1.5A 2 5 % TL SENSE 0C to +70C Current Sampling Rate t (Note 3) 200 s CSR Accumulator Resolution q 0.247 mAh CA t (Note 4) 1 3 ERR1 Internal Time-Base Accuracy % t (Note 4) 6.5 ERR2 Current-Sense Offset Measured with RS+ and RS- shorted -20 +20 mA 2 DS2741