IS31AP4912 Stereo Headphone Driver Evaluation Board Guide
Integrated Silicon Solution, Inc. – www.issi.com
2
RevA, 01/10/2013
Gain Setting
The input resistors R
IN
(R2, R3) and feedback resistors
R
F
(R1, R5) set the gain of the amplifier according to
Equation (1).
IN
F
R
R
ain
=
G
V
V
(1)
*Note:
Please refer to the datasheet to get more information about
IS31AP4912.
High Pass Filter
The input capacitors (C6, C7) and input resistors (R2,
R3) form a high pass filter with the corner frequency, f
C
,
determined in Equation (2).
IN
IN
C
R
c
f
π
2
1
=
(2)
Shutdown mode
Close Jumper (JP1) enter shutdown mode.
CON2
AUDIO IN
R2
20k
R3
20k
R4
100k
C6
0.47uF
C7
0.47uF
VCC
C9
2.2uF
C3
1uF
C4
0.1uF
R1
20k
R5
20k
C5
2.2uF
C2
6.8pF
C10
6.8pF
CON3
HP JACK
VCC
JP1
CLOSE=SD
INL
TP5
INR
TP3
TP4
OUTR
TP6
OUTL
TP8
TP7
CN
1
INR
2
OUTL
4
INL
3
SDB
5
S
G
N
D
6
P
V
D
D
7
VREF
8
CP
10
P
G
N
D
1
1
OUTR
9
P
V
S
S
1
2
U1
IS31AP4912
C8
2.2uF
VCC
C1
10uF
CON1
DC IN
TP1
TP2
Figure 2: IS31AP4912 Application Schematic
