WM9713L_06 WOLFSON [Wolfson Microelectronics plc], WM9713L_06 Datasheet - Page 100

• Manufacturer Part Number: WM9713L_06
• Description: AC 97 Audio + Touchpanel CODEC
• Manufacturer: WOLFSON [Wolfson Microelectronics plc]

WM9713L
LINE OUTPUT
AC-COUPLED HEADPHONE OUTPUT
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The headphone outputs, HPL and HPR, can be used as stereo line outputs. The speaker outputs,
SPKL and SPKR, can also be used as line outputs. Recommended external components are shown
below.
Figure 35 Recommended Circuit for Line Output
The DC blocking capacitors and the load resistance together determine the lower cut-off frequency,
fc. Assuming a 10 k
fc = 1 / 2 (R
Increasing the capacitance lowers fc, improving the bass response. Smaller values of C1 and C2 will
diminish the bass response. The function of R1 and R2 is to protect the line outputs from damage
when used improperly.
The circuit diagram below shows how to connect a stereo headphone to the WM9713L.
Figure 36 Simple Headphone Output Circuit Diagram
The DC blocking capacitors C1 and C2 together with the load resistance determine the lower cut-off
frequency, fc. Increasing the capacitance lowers fc, improving the bass response. Smaller
capacitance values will diminish the bass response. For example, with a 16
fc = 1 / 2 R
L
L
C
+R
1
= 1 / (2 x 16
1
) C
1
= 1 / (2 x 10.1k
load and C1, C2 = 10 F:
x 220 F) = 45 Hz
x 1 F) = 16 Hz
load and C1 = 220 F:
PP Rev 3.0 June 2006
Pre-Production
100