TA2131FN

2002-04-19

8

<Principle of Low-Pass Compensation>

possible to increase the gain only of the low-pass component. The frequency characteristics of the

power amplifier output V (OUT) in this state are shown in Fig.4 (b). In practice they are the

relative to the state in (a).

2-2.

Low-Pass Compensation Condenser and Crosstalk

In this low-pass compensation condenser circuit, processing is carried out using the composite

signal of power amplifier output, so this affects crosstalk, according to the amount of compensation.

f characteristics and crosstalk generated by the capacity of the condenser for compensation (2-pin) are

shown below.

f

(Hz)

(b)

(c)

(a)

1

10

100

1 k

10 k

100 k

0

10

20

-20

-10

Figure 4

Power Amplifier Frequency Characteristics

VCC1 = 2.8 V

VCC2 = 1.2 V

Rg = 620 W

RL = 16 W

Filter: LPF 80 kHz

Output C

= 220 mF

10

0

-10

10

30

100

300

1 k

3 k

10 k

30 k

C

= 0.47 mF

C

= 2.2 mF

C

= 1 mF

Vref short

f

(Hz)

Figure 5

Condenser and f Characteristics for Low-Pass Compensation