tb2901h TOSHIBA Semiconductor CORPORATION, tb2901h Datasheet - Page 3

• Manufacturer Part Number: tb2901h
• Description: Maximum Power 47 W Btl 4-ch Audio Power Ic
• Manufacturer: TOSHIBA Semiconductor CORPORATION

Caution and Application Method
(Description is made only on the single channel.)
1. Voltage Gain Adjustment
2. Standby SW Function
When changing the time constant of pin 4, check the
pop noise.
High and Low, the power supply can be set to ON
and OFF. The threshold voltage of pin 4 is set at
about 3V
about 2 mA (typ.) in the standby state.
Control Voltage of Pin 4: V
Advantage of Standby SW
(1)
the device a space and total costs saver.
(2)
This IC has no NF (negative feedback) Pins. Therefore, the voltage gain can not be adjusted, but it makes
Therefore, the total voltage gain is decided by expression below.
By means of controlling pin 4 (standby pin) to
Standby
OFF
ON
The voltage gain of amp.1
The voltage gain of amp.2A, B
The voltage gain of BTL connection : G
G
Since V
omitted.
Since the control current is microscopic, the switching relay of small current capacity is satisfactory
for switching.
V
BE
= G
(typ.), and the power supply current is
V1
CC
+ G
can directly be controlled to ON or OFF by the microcomputer, the switching relay can be
Power
OFF
ON
V2
+ G
V (BTL)
Input
(pin 4)
V
3.5~6 V
0~1.5
SB
Figure 1 Block Diagram
SB
= 0 + 20 + 6 = 26dB
(V)
Amp. 1
: G
: G
V1
V2
V (BTL)
= 0dB
= 20dB
3
= 6dB
Amp. 2A
OFF
ON
Amp. 2B
Figure 2 With pin 4 set to High,
Power
4
10 kW
Power is turned ON
V
CC
» 2 V
BE
to BIAS
CUTTING CIRCUIT
2002-11-06
TB2901H