TA8258HQ Toshiba, TA8258HQ Datasheet - Page 3

• Manufacturer Part Number: TA8258HQ
• Manufacturer: Toshiba

Specifications of TA8258HQ

• No. Of Channels: 2
• Package: HZIP 12-P-1.78
• Recommended Vcc (v): 37
• Rl=2 Ohm: -
• Rl=4 Ohm: -
• Rl=8 Ohm: 20W x 2
• Features/built-in Functions: 2 channels, muting function, output shorting (AC)/thermal shutdown protection circuit.
• Operating Voltage (v): 15 to 42

Note 1: Since the oscillation allowance varies according to the PCB layout, it is recommended that a standard
2. Muting
3. The Mounting Place of an Integrated Circuit
4. Preventive Measures Against Oscillation
(1)
(2)
the device to exhibit malfunctions such as leakage.
Please ensure that the IC is kept away from CRT.
temperature and frequency fluctuation characteristics, as C.
The resistance R in series with C performs phase correction at high frequencies and improves the
oscillation allowance.
(1)
(2)
This product has an excellent muting system.
This IC cannot withstand the strong electromagnetic fields generated by a CRT. These are likely to cause
To prevent oscillation, it is advisable to use capacitors made of polyester film, which have low
Toshiba PCB be used as a reference for design.
Audio muting
IC internal muting at V
This IC is possible to make audio muting operation by using 11 pin muting terminal.
Figure 3 shows the equivalent circuit in the muting circuit.
By reducing the voltage of 11 pin to 2.8 V or less, Q
Also the base voltage of Q
When Q
However, the bias circuit is operating after muting, and it takes power supply current at no signal.
8 pin is the capacitor terminal for reducing the pop noise, and it can make the time constant longer by
inserting the capacitor externally. If 11 pin is not used, connect 11 pin and 8 pin, then set the voltage
abode 4 V.
When V
Q
Capacitor rating and type
PCB layout
1
is reduced and the muting is operated in IC.
The detection
V
Reference
CC
2
CC
circuit at
voltage
is OFF, I
Mute
= 8 V or less at V
→ OFF
11
Q
1
2
and I
8
CC
Mute. TC
5
OFF
Q
2
I
dummy circuits will be operated, and it will shut down the input.
2
in the differential circuit that has Q
1
CC
Q
off, the detection circuit at V
3
I
2
The
reference
voltage is
equal.
Figure 3
3
I
3
1
Dummy amp.
Q
30 kΩ
I
4
will be ON.
4
2/4
IN
Q
I
5
5
CC
Q
I
6
6
2
off is operated. And the base voltage of
Q
and Q
10
Main amp.
Q
7
3
I
Q
7
will be down.
8
Q
Q
11
9
1/5
NF
20 kΩ
OUT
TA8258HQ
V
2004-04-06
CC
7/12
9