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TOSHIBA Bipolar Linear Integrated Circuit Silicon Monolithic
TA8225H,TA8225L
TA8225H/L
45W BTL Audio Amplifier
The TA8225H, TA8225L is BTL audio power amplifier for consumer application. It is designed for high power, low distortion and low noise. It contains various kind of protectors and the function of stand−by SW. In addition, the functions of output short or over voltage detection and junction temperature are involved.
Features
· High power
: POUT (1) = 45W (typ.) (VCC = 14.4V, f = 1kHz, THD = 10%, RL = 2Ω) : POUT (2) = 40W (typ.) (VCC = 13.2V, f = 1kHz, THD = 10%, RL = 2Ω) : POUT (3) = 24W (typ.) (VCC = 13.2V, f = 1kHz, THD = 10%, RL = 4Ω)
· Low thermal resistance : θj−c = 1.5°C / W (infinite heat sink)
· Excellent output power band width : POUT (4) = 18W (typ.) (VCC = 13.2V, f = 50Hz~20kHz, THD = 1%, RL = 4Ω)
Weight HZIP17−P−2.00: 9.8g (typ.) HSIP17−P−2.00: 9.8g (typ.)
· Low distortion ratio : THD = 0.015% (typ.) (VCC = 13.2V, f = 1kHz, POUT = 4W, RL = 4Ω)
· Built−in stand−by function (with pin(1) set at high, power is turned on)
· Built−in output short or over voltage detection circuit, output to VCC and output to GND short. (Pin(8): Open collector)
· Built−in junction temperature detection circuit. (Pin(2): Open collector)
· Built−in various protection circuits
· Thermal shut down, Over voltage
· Output to GND short
· Output to VCC short
· Output to Output short
· Operating supply voltage: VCC (opr) = 9~18V
1 2002-10-30
Block Diagram
TA8225H/L
Caution For Use And Method Of Application
1. Voltage gain adjustment
Voltage gain GV of this IC is decided by the external feedback resistors Rf1 and Rf2. Gain fluctuation by temperature can be made smaller than they are
housed in IC.
Voltage gain GV is decided by the following expression:
If R0 = 20kΩ≫Rf1 > Rf2
GV≒20ℓog
Rf1 + Rf2 Rf2
+ 6 (dB)
If R0 = 20kΩ > Rf1 > Rf2
GV≒20ℓog
(R0
// Rf1) + Rf2 Rf2
+ 6 (dB)
If Rf1 and Rf2 are made small, the following problems may be caused: (1) When output short is released, output DC voltage is not restored. (2) Fluctuation of output DC voltage by current I in (Fig.1).
If voltage gain is made small excessively, oscillation may be taken place and therefore, this IC shall be used at GV = 34dB or above.
2 2002-10-30
TA8225H/L
2. Preventive measure against oscillation
For preventing the oscillation, it is advisable to use C4, the condenser of polyester film having small
characteristic fluctuation of the temperature and the frequency.
The condenser (C6) between input and GND is effective for preventing oscillacion which is generated with
feedback signal from an output stage.
The resistance R to be series applied to C4 is effective for phase correction of high frequency, and improves the
oscillation allowance.
Since the oscillation allowance is varied according to the causes described below, perform the temperature test
to check the oscillation allowance.
(1) Voltage gain to be used (GV setting) (2) Capacity value of condense.