DN1• 6
We designed our kit to change quickly and easily adapt to a variety of cell or
battery pack types for anything from video camcorders to cordless phones.
You can configure it for the number of batteries in your pack, discharge and
charging rate. We’ll discuss this later as we’re assembling these sections of
the circuit.
DN1 CIRCUIT DESCRIPTION
Before we get into the technical jargon, let’s take a walk around the BQ2003
Integrated Circuit . We’ll start with some definitions of the abbreviations
written on the chip in the schematic diagram.
The BQ2003 charger IC handles many of the functions related to our
charger. Without trying to sound too much like a technical manual or data
book, here’s a closer look at some of the accompanying circuitry. Have a
glance at the schematic diagram and follow along.
Pin No. Abbreviation Function
1 CCMD Charge command
2 DCMD Discharge Before Charge Command
3 DVEN - ∆V Enable Input
4,5 TM1 & 2 Timer Mode Outputs
7 BAT Single Cell Voltage Input
8 VSS Ground
9 SNS Charging Current Sense Input
11 MCV Maximum Cell Voltage Reference
13 CHG Charging Status LED Output
14 MOD Current Switching Control Output
15 DIS Discharge Control Output
16 VCC 5 Volt input
Benchmark BQ2003 pin designations: