 2003 Microchip Technology Inc.

Preliminary

DS21768A-page 3

PS4200

FIGURE 1-2:

BOARD ASSEMBLY (SIDE 1)

FIGURE 1-3:

BOARD ASSEMBLY (SIDE 2)

2.0

FUNCTIONAL DESCRIPTION

2.1

PS402 Fuel Gauge

The module fuel gauge provides State-of-Charge

(SOC) and battery status data in accordance with the

SMBus standards version 1.1. The PS402 monitors the

pack voltage, battery temperature and current to

determine SOC and battery status. The State-of-

Charge calculations are compensated for cell self

discharge and charge acceptance. The remaining time

calculation is compensated for temperature and

discharge rate. The parameters for determining battery

status flags and alarm thresholds are all programmable

as is the battery design capacity and the battery

performance model data. Please refer to the data sheet

"PS402

Single

Chip

Battery

Manager

-

Nickel

Chemistries" for details on configuring the PS402.

2.2

OTP EPROM Programming

To write to the OTP EPROM, an additional voltage

voltage can be obtained from the PowerInfo board and

applied to the PS4200 at connection VP (small

thru-hole) located on the small edge of the board

opposite the connector edge. Then use the utilities

located on the P4 OTP page of the PowerTool software

to write new values to the PS402 OTP EPROM.

C5

R32

R26

SW1

C1

R29

R1

R16

R36

C7

D3

R9

R8

U1

R6

R10

R7

C16

D1

D2

R5