BQ26220 Datasheet, PDF (6/19 Pages) Texas Instruments – HIGH PERFORMANCE BATTERY MONITOR IC WITH COULOMB COUNTER, VOLTAGE AND TEMPERATURE MEASUREMENT

bq26220
SLUS521B − AUGUST 2002 − REVISED FEBRUARY 2004
FUNCTIONAL BLOCK DIAGRAM
VCC
Bandgap,
Reference and
Bias
Temperature
Compensated
Precision
Oscillator
Timer
System I/O
and Control
GPIO
HDQ
SRP
SRN
Autocalibrating
VFC
RAM
User
RBI
Registers
Temperature
Sensor
BAT
VSS
Multiplexer
ADC
Flash
ID
UDG−02050
TERMINAL FUNCTIONS
TERMINAL
I/O
NAME
No.
BAT
5
I
RBI
1
I
GPIO
8
I/O
HDQ
4
I/O
SRN
6
I
SRP
7
I
VCC
2
I
VSS
3
−
DESCRIPTION
Battery voltage sense input. This pin is used for sensing and measuring the battery voltage.
Register backup input. The RBI input pin is used with a storage capacitor or external supply to
provide backup potential to the internal RAM and registers while VCC is < V(POR).
General-purpose input/output pin. GPIO is a general-purpose programmable input or output port
whose state is controlled via the HDQ serial communications interface.
Single-wire HDQ interface. HDQ is a single-wire serial communications interface port. This
bidirectional input/output communicates the register information to the host.
Current sense input 2. The bq26220 interprets charge and discharge activity by monitoring and
integrating the voltage drop, VSR, across pins SRP and SRN. The SRN input connects to the
sense resistor and the negative terminal of the pack. VSRP < VSRN indicates discharge, and
VSRP > VSRN indicates charge.
Current sense input 1. The bq26220 interprets charge and discharge activity by monitoring and
integrating the voltage drop, VSR, across pins SRP and SRN. The SRP input connects to the
sense resistor and the negative terminal of the battery. VSRP < VSRN indicates discharge, and
VSRP > VSRN indicates charge.
Supply voltage
Ground
6
www.ti.com