Gain Setting; High Pass Filter; Shutdown Mode; Figure 2: Is31Ap4912 Application Schematic - ISSI IS31AP4912 Manual

IS31AP4912 Stereo Headphone Driver Evaluation Board Guide

Gain Setting

The input resistors R (R2, R3) and feedback resistors
IN
R (R1, R5) set the gain of the amplifier according to
F
Equation (1).
R
F
G ain =
R
IN
*Note:
Please refer to the datasheet to get more information about
IS31AP4912.
TP1
VCC
CON1
C1
10uF
DC IN
TP2
TP5
INL
CON2
AUDIO IN
TP4
TP3
INR
Integrated Silicon Solution, Inc. – www.issi.com
RevA, 01/10/2013
 
V
 
(1)
 
V
C3
1uF
C4
0.1uF
C6 U1
R2
0.47uF
20k
3
INL
VCC
R4
JP1 100k
5
SDB
CLOSE=SD
C7
R3
0.47uF
20k
2
INR
IS31AP4912

Figure 2: IS31AP4912 Application Schematic

High Pass Filter

The input capacitors (C6, C7) and input resistors (R2,
R3) form a high pass filter with the corner frequency, f
determined in Equation (2).
1
f
=
c
2 R
π
IN

Shutdown mode

Close Jumper (JP1) enter shutdown mode.
C2
6.8pF
R1
20k
VCC
C5
2.2uF
4
OUTL
10
CP
C9
2.2uF
1
CN
8
VREF
C8
2.2uF
9
OUTR
R5
20k
C10
6.8pF
C
(2)
C
IN
TP8
OUTL
CON3
HP JACK
TP7
TP6
OUTR
2
,