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TA8210AH / AL
TOSHIBA Bipolar Linear Integrated Circuit Silicon Monolithic

20W BTL × 2ch Audio Power Amplifier

The thermal resistance θj−T of TA8210AH, TA8210AL package designed for low thermal resistance, has a high efficiency of heat radiation. The temperature rise of chip can be reduced, and the influence from the degradation of the features due to the temperaturerise at the high output can also be reduced. This stereo audio power IC, designed for car audio use, has two built−in channels to reduce the characteristic difference between L and R channels. In addition, the functions of stand−by and muting, and a variety of protection circuits are involved.

· · Low thermal resistance : θj−T = 1.5°C / W (infinite heat sink) High power : POUT (1) = 22W(typ.) / channel (VCC = 14.4V, f = 1kHz, THD = 10%, RL = 4Ω) POUT (2) = 19W (typ.) / channel (VCC = 13.2V, f = 1kHz, THD = 10%, RL = 4Ω) · · · · · · Weight HZIP17−P−2.00: 9.8g (typ.) HSIP17−P−2.00: 9.8g (typ.)

Low distortion ratio: THD = 0.04% (typ.) (VCC = 13.2V, f = 1kHz, POUT = 1W, RL = 4Ω, GV = 50dB) Low noise: VNO = 0.30mVrms (typ.) (VCC = 13.2V, RL = 4Ω, GV 50dB, Rg = 0Ω, BW = 20Hz~20kHz)Built−in stand−by function (with pin(4) set at low, power is turned off.): ISB = 1µA (typ.) Built−in muting function (with pin(1) set at low, power is turned off.): V (mute) = 1V (typ.) Built−in various protection circuits Protection circuits: Thermal shut down, Over voltage, Out→VCC short, Out→GND short and Out−Out short. Operating supply voltage: VCC = 9~18V



TA8210AH / ALBlock Diagram
TA8210AH, TA8210AL (GV = 50dB)

Cautions And Application Method
1. Voltage gain adjustment

(description is made only on the single channel.)

This IC has the amplifier construction as shown in Fig.1. The pre-amp (amp 1) is provided to the primary stage, and the input voltage is amplified by the flat amps, amp 3 and amp 4 of each channel through the phase amp. (Amp 2).Since the input offset is prevented by pre-amp when VCC is set to on, this circuit can remarkably reduce the pop noise.



TA8210AH / AL
The total closed loop gain GV of this IC can be obtained by expression below when the closed loop voltage gain of amp 1 is GV1.
G V1 = 20log R1 + (R f + R2) (dB) R f + R2



The closed loop voltage gain of power amp, amp 3 andamp 4 is fixed at GV3≒GV4 = 20dB. Therefore, the total closed circuit voltage gain GV is obtained through BTL connection by the expression below. GV = GV1 + GV3 + 6 (dB) ............... (2) For example, when Rf = 0Ω, GV is obtained by the expressions (1) and (2) as shown below. GV≒24 + 20 + 6 = 50dB The voltage gain is reduced when Rf is increased. (Fig.2) With the voltage gain reduced, since (1)the oscillation stability is reduced, and (2) the pop noise changes when VCC is set to on, refer to the items 3 and 4.

2. Stand-by SW function By means of controlling pin(4) (stand-by terminal) to high and low, the power supply can be set to on and off. The threshold voltage of pin(4) is set at 2.1V (3VBE.), and the power supply current is about 1µA (typ.) at the stand-by state. Pin(4)control voltage : V (SB)
Stand-by On Off Power Off On V (SB) (V) 0~2 3~VCC Fig.3 With pin(4) set to high, power is on.

Advantage of stand-by SW (1) Since VCC can directly be controlled to on / off by the microcomputer, the switching relay can be omitted. (2) Since the control current is microscopic, the switching relay of small current capacity is satisfactory for switching.


2002-10-30 TA8210AH / AL

3. 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 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...
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