ST AN3075 APPLICATION NOTE

AN3075

Application note

Demonstration board user guidelines for the

STC3100 battery monitor for gas gauge applications

Introduction

This application note describes the STEVAL-ISB009V1, a demonstration board specifically
designed for the STC3100 integrated circuit.

The document provides:

● a brief description of the STC3100 device.

● a description of the demonstration board.

● a detailed bill of materials for the demonstration board.

● the layout of the demonstration board.

Figure 1. Demonstration board

October 2009 Doc ID 16365 Rev 1 1/9

www.st.com

About the STC3100 AN3075

1 About the STC3100

The STC3100 monitors the three main battery parameters: voltage, current and
temperature, and includes a Coulomb counter to keep track of the charge/discharge status.

1.1 Features

● Accurate battery voltage measurement

● Coulomb counter to keep track of the battery’s state-of-charge

● Internal temperature sensor

● Internal or external 32 kHz timebase

● I2C interface for battery monitoring and device control

1.2 Performances:

● 0.5% battery voltage accuracy

● 1% Coulomb counter accuracy using an external RTC signal (3.5% using the internal

timebase).

● Low power consumption: 100 µA in operating conditions, 2 µA in standby mode.

1.3 Packages

● DFN8 3 x 3 (as used in the demonstration board)

● MiniSO-8

Refer to the STC3100 datasheet for more detailed information on the device.

2/9 Doc ID 16365 Rev 1

AN3075 About the STC3100

Figure 2. Typical application diagram for the STC3100

Battery State-of-charge

Remaining percentage

Remaining time

2:06

uC with

Gas Gauge

firmware

80 %

32768 Hz

clock

I2C bus

Battery data

Current

Voltage

Temperature

ROSC

SCL

SDA

0.32 A

3.71 V

STC3100

GND

27 ° C

VCC

VIN

CG

IO0

Battery

Rcg

AM04578

Doc ID 16365 Rev 1 3/9