CRD42L51 Cirrus Logic Inc, CRD42L51 Datasheet - Page 19

• Manufacturer Part Number: CRD42L51
• Description: Ref Bd Low-voltage Stereo Codec
• Manufacturer: Cirrus Logic Inc

DS679F1
HEADPHONE OUTPUT POWER CHARACTERISTICS
Test conditions (unless otherwise specified): Input test signal is a full-scale 997 Hz sine wave; measurement band-
width is 10 Hz to 20 kHz; Sample Frequency = 48 kHz; test load R
Parameter
AOUTx Power Into R
HP_GAIN[2:0]
000
001
010
011 (default)
100
101
110
111
8. One-half LSB of triangular PDF dither is added to data.
9. Full-scale output voltage and power is determined by the gain setting, G, in register
10. See
11. VA_HP settings lower than VA reduces the headroom of the headphone amplifier. As a result, the DAC
Gain (HP_GAIN[2:0])” on page
cause clipping when the audio signal approaches full-scale, maximum power output, as shown in
Figures 27
quired for the internal op-amp's stability and signal integrity. In this circuit topology, C
move the band-limiting pole of the amp in the output stage. Increasing this value beyond the recom-
mended 150 pF can cause the internal op-amp to become unstable.
may not achieve the full THD+N performance at full-scale output voltage and power.
Figure
Analog
Gain (G)
0.3959
0.4571
0.5111
0.6047
0.7099
0.8399
1.0000
1.1430
L
-
3. R
= 16
30 on page
L
Ω
and C
VA_HP
1.8 V
2.5 V
1.8 V
2.5 V
1.8 V
2.5 V
1.8 V
2.5 V
1.8 V
2.5 V
1.8 V
2.5 V
1.8 V
2.5 V
1.8 V
2.5 V
L
76.
reflect the recommended minimum resistance and maximum capacitance re-
Figure 3. Headphone Output Test Load
AGND
AOUTx
57. High gain settings at certain VA and VA_HP supply levels may
Min
-
-
-
-
-
-
-
-
VA = 2.5V (nominal)
0.022 µF
51 Ω
(Note 11)
(Note 11)
Typ
14
14
19
19
23
23
32
44
C
L
Max
L
= 16 Ω, C
-
-
-
-
-
-
-
-
(Note 9, 11)
R
L
Min
L
-
-
-
-
-
-
-
-
-
-
-
= 10 pF (see
VA = 1.8V (nominal)
(Note 9)
Typ
10
10
12
12
17
17
23
23
32
7
7
Figure
“Headphone Analog
Max
L
3).
-
-
-
-
-
-
-
-
-
-
-
will effectively
CS42L51
mW
mW
mW
mW
mW
mW
mW
mW
mW
mW
mW
mW
mW
mW
mW
mW
Unit
rms
rms
rms
rms
rms
rms
rms
rms
rms
rms
rms
rms
rms
rms
rms
rms
19