TA8255AHQ TOSHIBA Semiconductor CORPORATION, TA8255AHQ Datasheet - Page 3

• Manufacturer Part Number: TA8255AHQ
• Description: Max Power 22w Btl ? 4ch Audio Power Ic
• Manufacturer: TOSHIBA Semiconductor CORPORATION

Caution And Application Method
(description is made only on the single channel.)
1. Voltage gain adjustment
2. Stand−by SW function
This IC has no NF (negative feedback) terminals. Therefore, the voltage gain can’t adjusted, but it makes the
device a space and total costs saver.
Therefore, the total voltage gain is decided by expression below.
By means of controlling pin(2) (stand−by terminal) to high
and low, the power supply can be set to on and off.
The threshold voltage of pin(2) is set at about 3V (typ.),
and the power supply current is about 100 µA (typ.) at the
stand−by state.
Adjustage of stand−by SW
(1) Since V
(2) Since the control current is microscopic, the switching relay of small current capacity is satisfactory for
Control voltage of pin(2): V
microcomputer, the switching relay can be omitted.
switching
Stand−by
The voltage gain of amp. 1: G
The voltage gain of amp. 2A, B: G
The voltage gain of BTL connection: G
On
Off
G
V
CC
= G
can directly be controlled to on or off by the
V1
+ G
Power
V2
Off
On
+ G
(SB)
V (BTL)
V1
V
= 0 + 28 + 6 = 34 dB
= 0 dB
3~V
(SB)
V2
0~2
CC
= 28 dB
(V)
V (BTL)
= 6 dB
3
TA8255AHQ
2006-04-28