Sony NW-A1000 / NW-A1200 Service Manual ▷ View online
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Fig.3-1 Playback Circuit -1
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3-2. Playback Operation-2
Fig. 3-2 shows Playback Circuit - 2.
1. D/A CONVERTER IC3002
D/A CONVERTER IC3002 outputs analog signals; L-ch from pin-9 [VOUTL] and R-ch from pin-7 [VOUTR].
D/A CONVERTER IC3002 outputs analog signals; L-ch from pin-9 [VOUTL] and R-ch from pin-7 [VOUTR].
2. HEADPHONE AMPLIFIER IC3003
The L-ch and R-ch analog signals output from D/A CONVERTER IC3002 are output from HEADPHONES JACK J301 via HEADPHONE AMPLIFIER IC3003.
The HEADPHONE AMPLIFIER IC3003 has the following functions controlled by PLD IC8001. Table.3-1 shows the details of the controls.
The L-ch and R-ch analog signals output from D/A CONVERTER IC3002 are output from HEADPHONES JACK J301 via HEADPHONE AMPLIFIER IC3003.
The HEADPHONE AMPLIFIER IC3003 has the following functions controlled by PLD IC8001. Table.3-1 shows the details of the controls.
MUTE function
BEEP function
HP/LINE Select function
BEEP function
HP/LINE Select function
Table.3-1 Controls by PLD IC8001
Description of terminal
IC8001 Pin-38 [HP_MUTE]
Turning “ON” and “OFF” of the mute circuit inside IC3003 (H: “OFF”, L: “ON”)
IC8001 Pin-66 [PLD_BEEP]
BEEP output terminal
IC8001 Pin-45 [HP_LINE_SEL]
Selecting “HP” or “LINE” inside IC3003 (L: “HP”, H: “LINE”)
3. Sound Output to Multiple Connector
= When the unit is not connected to Cradle =
When Power Control IC9001 wakes up, 5.0V voltage is generated by IC9001. By this 5.0V voltage, Q3005 and Q3006 turn “OFF”. And also, Q3007 turns “ON” by VSTBY
voltage supplied from IC9001. Then, analog signals are not supplied to Multiple Connector because Q1002 and Q2002 turn “OFF”.
= When the unit is connected to Cradle =
When the unit detects that any of the following conditions is satisfied, PLD IC8001 outputs “H” signal from pin-43 [CRD_MUTE1]. By this “H” signal, Q3003 turns “ON”.
Then, analog signals are not supplied to Headphones Jack J301 because Q3005 and Q3006 turn “OFF”. On the other hand, Q1002 and Q2002 turn “ON” as Q3007 turns
“OFF”. Then, analog signals are supplied to Multiple Connector.
Conditions:
When the unit is connected to the optional cradle (BCR-NWU1) and the plug is inserted into the lineout jack of the cradle.
When the unit is connected to the optional dock speaker (SRS-NWM10)
One Point:
When PLD IC8001 detects that any of the above conditions is satisfied, it outputs “H” signal from pin-45 [HP_LINE_SEL] automatically to let IC3003 use the line amplifier.
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Fig3-2 Playback Circuit-2
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4. Charging Circuit
4-1. Charging Circuit
Fig.4-1 shows the charging circuit. In this model, the charge control IC9001 controls all charge operation. When IC9001 detects that the following conditions are satisfied,
Charge Control IC9001 starts operation corresponding to Table.4-1.
- Voltage from the rechargeable battery is lower than 4.2[V].
- DCIN_5V voltage or VBUS voltage is supplied to POWER CONTROL IC9001
Table.4-1 Power Source Selection
AC (DCIN)
USB (VBUS)
Charging Source
System Power Source
Present
Absent
AC
AC
Absent
Present
USB
USB
Present
Present
AC
AC
Absent
Absent
N/A
Battery
= Charging operation with the power supplied from AC power adapter =
As a rechargeable Lithium-ion Battery is built into the unit, the charging method is the constant current and constant voltage method. CHARGE CONTROL IC9001 performs
the constant current charging with the charging current shown in Table.4-6. When the constant current charging terminates, IC9001 changes the mode from the constant
current charging method to the constant voltage charging method.
= Charging operation with VBUS voltage =
As a rechargeable Lithium-ion Battery is built into the unit, the charging method is the constant current and constant voltage method. CHARGE CONTROL IC9001 performs
the constant current charging with the charging current shown in Table.4-6. In this unit, PLD IC8001 controls the charging current depending on the current which is supplied
from PC (See Table.4-2). When the constant current charging terminates, IC9001 changes the mode from the constant current charging method to the constant voltage
charging method.
Table.4-2 Charging Control by PLD IC8001
Output Terminal
500[mA]- Permit
100[mA]- Permit
Description
IC8001 Pin-27 [VBUS_LIM]
L
H
Charging current control terminal during USB charging
Note that at the present specifications, “L” is always output.
Note that at the present specifications, “L” is always output.
During USB charging, PLD IC8001 monitors the PC operation. If IC8001 detects that PC is in SUSPEND mode, IC8001 outputs “H” signal from Pin-56 [SUSPEND].
By this “H” signal, Q9009 (2/2) and Q9005 turn “OFF”. Then, VBUS voltage is not supplied to Power Control IC9001 and the charging operation ends.
Table.4-3 Charging Control by PLD IC8001
Output Terminal
PC: SUSPEND
PC: Normal
Description
IC8001 Pin-56 [SUSPEND]
H
L
Charging operation stops when PC is in SUSPEND mode.
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