Demonstration circuit 1496C-A features the LTC2941. Demonstration circuit 1496C-B features the LTC2942. Demonstration circuit 1496C-C features the LTC2941-1. Demonstration circuit 1496C-D features the LTC2942-1. The C, D options have parts that use an internal sense resistor while the A, B options rely on an external precision sense resistor. All four devices measure battery charge state in handheld PC and portable product applications. The operating range is perfectly suited for single cell Li-Ion batteries. A precision analog coulomb counter integrates current through a sense resistor between the battery’s positive terminal and the load or charger. The LTC2942 adds battery voltage and on-chip temperature measurement with an internal 14-bit No Latency ΔΣ™ ADC. The three measured quantities (charge, voltage and temperature) are stored in internal registers accessible via the onboard SMBus/I2C interface.