CS42L51_07 Datasheet, PDF (34/88 Pages) Cirrus Logic – Low Power, Stereo CODEC with Headphone Amp

CS42L51
4.4 Analog Outputs
AOUTA and AOUTB are the ground-centered line or headphone outputs. Various signal processing options
are available, including digital mixes with the ADC signal and an internal Beep Generator. The desired path
to the DAC must be selected using the DATA_SEL[1:0] bits.
Software
Controls:
“DAC Control (Address 09h)” on page 58.
SIGNAL PROCESSING ENGINE (SPE)
MUTE_PCMMIXA
MUTE_PCMMIXB
PCMMIXA_VOL[6:0]
DEEMPH ^{PCMMIXB_VOL[6:0]}
+12dB/-51.5dB
0.5dB steps
Demph
VOL
OUTA_VOL[7:0]
OUTB_VOL[7:0]
+12dB/-102dB
0.5dB steps
Chnl Vol.
Settings
PCMA[1:0]
PCMB[1:0]
Channel
Swap
BPVOL[4:0]
0dB/-50dB
2.0dB steps
VOL
Σ
VOL
DAC_SZC[1:0]
DACA_MUTE
DACB_MUTE
INV_DACA
INV_DACB
DAC_SNGVOL
AMUTE
ARATE[7:0]
RRATE[7:0]
MAX[2:0]
MIN[2:0]
LIM_SRDIS
LIM_ZCDIS
LIMIT_EN
Limiter
TC_EN
Peak
Detect
Bass/
Treble/
Control
BASS_CF[1:0]
TREB_CF[1:0]
BASS[3:0]
TREB[3:0]
+12.0dB/-10.5dB
1.5dB steps
DATA_SEL[1:0]
PDN_DACA
PDN_DACB
HP_GAIN[2:0]
Switched
Headphone
01
Capacitor DAC
Amp - GND
Left/Right
and Filter
Centered
HP Out
00
Charge
Pump
CHRG_FREQ[3:0]
OFFTIME[2:0]
ONTIME[3:0]
FREQ[3:0]
REPEAT
BEEP
Beep
Generator
Figure 13. Output Architecture
4.4.1
De-Emphasis Filter
The CODEC includes on-chip digital de-emphasis optimized for a sample rate of 44.1 kHz. The filter re-
sponse is shown in Figure 14. The de-emphasis feature is included to accommodate audio recordings
that utilize 50/15 µs pre-emphasis equalization as a means of noise reduction. De-emphasis is only avail-
able in Single-Speed Mode.
Software
Controls:
Hardware
Control:
“DAC Control (Address 09h)” on page 58.
Pin
Setting
“DEM” pin 4. ^LO
HI
Selection
No De-Emphasis
De-Emphasis Applied
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