YAC520

5

s Description of analog functions

• Maximum input voltage

As described in the following figure, the maximum amplitude of signal that can be inputted varies

according the method of the use of L(R) IN1 and 2 pins. The method A makes the maximum

amplitude of the input signal approximately 2 Vrms, the method B makes it approximately 2.6 Vrms,

and the method C makes it approximately 7.9 Vrms. The use of the method B or C allows to input

signal exceeding the power supply voltage.

Note that the gain setting range for the method B is reduced by 2.5 dB from the one for the method A,

and 12 dB for the method C.

• VREF (analog reference voltage) stabilization time and DC bias initialization time

The time required for stabilization of VREF pin voltage after power on moment varies according to

the capacitance of the capacitor connected to VREF pin. Connecting a capacitor of 10

µF makes the

time constant 30 ms (typ.). Note that the serial interface becomes invalid in this period, t

As shown in the following figure, making ICN terminal “low” sets the DC bias forcibly with SW in the

LSI.

Since the time constant of L(R) IN1 and 2 pins becomes approximately 300 ms (typ.) when a

capacitor of 100

µF is used as the coupling capacitors (Ci1, 2), control ICN according to the capacitor

that is connected.

+

-

VREF

L(R)OUT

L(R) IN1

• • • •

L(R) IN2

Ri(1)

Ri(2)

Rf

MethodA: IN1=IN2

Gain range (+32 dB to –95 dB)

Maximum input voltage: 2 Vrms

+

-

VREF

L(R)OUT

L(R) IN1

• • • •

L(R) IN2

MethodB: IN2=GND

Gain range (+29.5 dB to –97.5 dB)

Maximum input voltage: 2.6 Vrms

Ri(1)

Ri(2)

Rf

+

-

VREF

L(R)OUT

L(R) IN1

• • • •

L(R) IN2

MethodC: IN1=GND

Gain range (+20 dB to –107 dB)

Maximum input voltage: 7.9 Vrms

Ri(1)

Ri(2)

Rf

+

-

VREF

L(R)OUT

L(R) IN1

L(R) IN2

Ri1=0.98k

Ω

Ri2=2.94k

Ω

Rf=29.3k

Ω

Ci1

Ci2

ICN

Rsw= 80

Ω (typ)

Gain setting after power on = -

Audio

Source

SW