Read Sony NW-E002 / NW-E002F / NW-E003 / NW-E003F / NW-E005 / NW-E005F Service Manual online
Copying is strictly prohibited
15
3. Charging Circuit
3-1. Charging Circuit
Fig.3-1 shows the charging circuit. In this model, System Controller IC101 controls ON/OFF of the charging circuit. When any of the following conditions is satisfied, IC101
outputs “L” signal from pin-101 [XCHG_EN]. By this “L” signal, Power Control IC601 starts charging.
Charging Condition:
A rechargeable battery is connected to the unit. (This unit has the built-in rechargeable Lithium-ion battery.)
VBUS voltage is supplied to the unit.
Table.3-1 Identification of Power Source
Terminal
When the unit is not
connected to PC
When the unit is
connected to PC
Description
IC101 pin-127 [VBUS]
H
L
Confirm whether VBUS voltage is supplied or not.
IC101 pin-84 [AN7]
H
H
Input terminal for monitoring the battery voltage
IC101 pin-101 [XCHG_EN]
H
L
Output terminal for controlling the charge operation
(L: Charge ON, H: Charge OFF)
(L: Charge ON, H: Charge OFF)
= Charging operation =
As the unit has a built-in rechargeable lithium-ion battery, the charging method is the constant current and constant voltage method. The charge current is set by ISET. ISET is
controllable by the external register connected to pin-12 [CHG_ISET] of IC601. The control signal from pin-102 [CHG_XLOW] of System Controller IC101 controls the charge
current and operates the charge with the current shown in Table 3-5. When the constant current charging terminates, Power Control IC601 shifts to the constant voltage
charging mode and operates the charge.
Table.3-2 Charging Control by System Controller IC101
Output Terminal
500[mA]- Permit
100[mA]- Permit
Description
IC101 pin-102 [CHG_XLOW]
H
L
Charging current control terminal during USB charging
Click on the first or last page to see other NW-E002 / NW-E002F / NW-E003 / NW-E003F / NW-E005 / NW-E005F service manuals if exist.