STC3100IQT

STC3100 Battery monitor IC with Coulomb counter/gas gauge Features ■ Battery voltage monitoring ■ Internal temperature sensor ■ Coulomb counter with 12/14-bit AD converter, +/- 80 mV input voltage range ■ Internal or external 32768 Hz time base ■ I2C interface for gas gauge monitoring and device control ■ 32-RAM bytes ■ 8-byte unique device ID ■ One general-purpose I/O MiniSO-8 (Plastic micropackage) DFN8 3x3 (Plastic micropackage) Applications ■ Cellular phones, PDA, MP3 players, cordless phones ■ Digital cameras, USB appliances, Bluetooth devices Pin connections (top view) IO0 ROSC SDA SCL Description The STC3100 monitors the critical parameters of a single-cell Li-Ion battery (voltage, temperature and current) and includes hardware functions to implement a gas gauge for battery charge monitoring, based on a programmable 12- to 14-bit A/D converter. With a typical 30 milliOhms external sense resistor, the battery current can be up to 2.5 A and the accumulator system provides a capacity up to +/-7000 mAh with a resolution of 0.2 mAh. 1 2 8 3 7 6 4 5 VIN VCC CG GND The device is programmable through the I2C interface. January 2009 Rev 1 1/21 www.st.com 21 Block diagram 1 STC3100 Block diagram Figure 1. STC3100 internal block diagram 1.2 V reference VCC 32 kHz time base AD converter 11 bits (unsigned) Accumulators and control registers General-purpose I/O line SDA ROSC Temp sensor MUX VIN CG+ AD converter 12 / 14 bits (signed) SCL Oscillator CG CG- IO0 I2C interface RAM & ID registers GND AM00830 2/21 STC3100 2 Pin assignment Pin assignment Table 1. Note: STC3100 pin description Pin # Pin name Type Function 1 IO0 I/OD General-purpose I/O 2 ROSC I_AD Oscillator bias resistor or external 32 kHz clock for gas gauge 3 SDA I/OD I2C serial data 4 SCL I_D I2C serial clock 5 GND Ground 6 CG I_A 7 VCC Supply 8 VIN I_A Analog and digital ground Gas gauge current sense input Power supply Battery voltage sense input I: input O: output OD: open drain A: analog D: digital 3/21 Absolute maximum ratings and operating conditions 3 Absolute maximum ratings and operating conditions Table 2. Absolute maximum ratings Symbol Vmax Parameter Maximum voltage on any pin Vio Voltage on I/O pins Tstg Storage temperature Tj ESD Table 3. Maximum junction temperature Electrostatic discharge (HBM human body model) Value Unit 7 V -0.3 to 7 V -55 to 150 °C 150 °C 2 kV Value Unit Operating conditions Symbol 4/21 STC3100 Parameter Vcc Operating supply voltage on VCC 2.7 to 5.5 V Vin Input voltage on Vin 0 to Vcc V 2.0 V -40 to 85 °C Vmin Minimum voltage on VCC for RAM content retention Toper Operating free air temperature range STC3100 Electrical characteristics 4 Electrical characteristics Table 4. Electrical characteristics (2.7 V < VCC < 4.5 V, -20° C to 70° C) Symbol Parameter Conditions Min Typ Max Units 100 uA Supply ICC Operating current consumption Average value over 4s Istby Current consumption in standby standby mode, inputs=0V 2 uA Ipdn Current consumption in power down VCC < UVLOth, inputs=0V 1 uA UVLOth Undervoltage threshold (VCC decreasing) 2.7 V UVLOhyst Undervoltage threshold hysteresis POR Power-on reset threshold 2.5 (VCC decreasing) 2.6 100 mV 2.0 V Gas gauge A/D converter Vin_gg Input voltage range -80 Iin Input current for CG pin ADC_res AD converter granularity 12 bits 13 bits 14 bits ADC_offset AD converter offset CG = 0V 12 bits 13 bits 14 bits ADC_time AD conversion time (32768Hz clock) 12 bits 13 bits 14 bits ADC_acc AD converter gain accuracy at full scale 25° C over temperature range Fosc Internal time base frequency Rosc = 200 kΩ, 0.1% Osc_acc Internal time base accuracy 25° C, VCC = 3.6 V over temperature and voltage ranges Fosc_ext External time base frequency range Cur_res Current register LSB value Chg_res Charge register LSB value (32,768 Hz clock) =Cur_res*2^12*0.5/3600 Global_ CG_acc Gas gauge accuracy (not including the external sense resistor tolerance) Using internal time base Using external time base +80 mV 500 nA 47.08 23.54 11.77 -2 -2 -3 uV uV uV 2 2 3 125 250 500 ms ms ms 0.5 1 32768 30 LSB LSB LSB % % Hz 2 % 2.5 % 70 kHz 11.77 uV 6.70 uV.h 3.5 1 % % 5/21 Electrical characteristics Table 4. STC3100 Electrical characteristics (2.7 V < VCC < 4.5 V, -20° C to 70° C) (continued) Symbol Parameter Conditions Min Typ Max Units 5 V Battery voltage and temperature a/d converter Vin_adc Input voltage range Vcc = 5 V LSB LSB value Voltage measurement Temperature measurement ADC_time AD conversion time (32,768 Hz clock) Volt_acc Battery voltage measurement accuracy 2.7 V