Table of Contents
Advertisement
MODELS: LT-2220 / LT-2240 / LT-3020 / LT-3040 / LT-3050
Table 1: Amp supply voltage(+B)
AMPVCC(for main)
SAMPVCC(for Sub Woofer)
Volume control is controlled by fading Volume1 /Volume2 DC signal to the amplifier Pin(#9).
Although the audio signals outputted from amplifier is sent to the SPEAKER, between the amplifier and
SPEAKER is a headphone terminal. If a headphone is connected, the audio signal to SPEAKER will be
interrupted and the audio signal will be sent to the headphone terminal.
3. Power circuit
Refer the LT-2220 / LT-3020 Power circuit block for the following.
The LT-2220 power supply is supplied from an AC adapter.
The LT-3020 power supply is supplied from a power supply board.
The LT-2220 has one connector for the inverter connection, the LT-3020 has two connectors.
Except for that, the circuit composition of the power supply is almost the same.
There are power supplies that are "always on" and "ON/OFF" with a control signal, as follows.
Power source
signal
20V
24V
8.5V
A12V
A9V
A8V
AMPVCC
SAMPVCC
S5V
SW5V
A30V
S3.3V
4.5V
D3.3V
A3.3V
AD3.3V
D1.9V
D2.5V
1.5V
LT-22XX
7.5V
9V
Voltage [V ]
"always on" or
"ON/OFF"
20
always on
24
ON/OFF
8.5
always on
12
ON/OFF
9
ON/OFF
8
always on
"30 : 9
ON/OFF
"22 :7.5
"30 : 12
ON/OFF
"22 :9
5
always on
5
ON/OFF
30
ON/OFF
3.3
always on
4.5
always on
3.3
ON/OFF
3.3
ON/OFF
3.3
always on
1.9
ON/OFF
2.5
ON/OFF
1.5
ON/OFF
LT-30XX
9V
12V
Control
Note
signal
-
"22 only
ON_24V
"30 only
-
"30 only
Psave2
Psave2
-
Psave3
Psave3
-
Psave1
Psave1
-
-
Psave1
Psave1
-
Psave1
Psave1
Psave1
Hide quick links:
Advertisement
Table of Contents
Troubleshooting
