Power Tree; Charging Circuit And External Power; Battery Support; Charger Support - Motorola W208 Manual

W208 Level 3 Circuit Description

15 Power Tree

16 Charging Circuit and External Power

We can obtain power from battery and external charger. Power source via the accessory
connector are not supported.

16.1 Battery Support

The Battery connecter J700
♦ Pin 1 – VBAT- (BATTGND)
♦ Pin 2 – BAT_TEMP
fed from the battery connector to
♦ Pin 3 – DATA-EPROM for charge/discharge control (No Used for W370/
W375)
♦ Pin 4 – VBAT+

16.2 Charger Support

When the battery voltage is less than 3.2V, and adapter is inserted, the charging system
will enter the 'Pre-CHARGE' mode. The pre-charging current will pass through
pre-charge path and charger IC
set the safe magnitude of pre-charging current.
When a charger is plugged in and
(P-MOSFET) to start charging process. The process starts charge state until
When the battery voltage is less than 3.2V (deeply discharged), the Battery Charge
Interface (BCI) of Triton-Lite
100mA) as soon as the charger is plugged-in. At this moment, software cannot control the
charging process. Until battery voltage
and then enter to normal charging status. The normal charge will start as constant current
mode (MAX current is 450mA). When the battery voltage is reach 4.15V, charging system
will enter the constant voltage mode till minimum current is less than 50mA, then the
charge process finishes. When the battery voltage
Figure 119: Power Distribution Tree
is made up of 4 contacts, these are
is used to measure the Battery temperature during charging,
Triton-Lite U103
U501 (ISL9200). The current limit resisters, (R511), are
VAC is less than 6.85V, the
will enter the pre-charge mode (charging current is under
VBAT
Service Engineering & Optimization
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Pin F8
Triton-Litw
is larger than 3.2V,
VBAT is higher than 4.2V,
Triton-Lite
will enable U502
VAC is full.
Triton-Lite will wake up
U502