User Manual
Table Of Contents
- 1. Pin Descriptions
- 2. Typical Connection Diagram
- 3. Characteristic and Specifications
- Recommended Operating Conditions
- Absolute Maximum Ratings
- Analog Input Characteristics
- ADC Digital Filter Characteristics
- Analog Output Characteristics
- Analog Passthrough Characteristics
- PWM Output Characteristics
- Headphone Output Power Characteristics
- Line Output Voltage Level Characteristics
- Combined DAC Interpolation and onChip Analog FIlter Response
- Switching Specifications - Serial Port
- Switching Specifications - I²C Control Port
- DC Electrical Characteristics
- Digital Interface Specifications and Characteristics
- Power Consumption
- 4. Applications
- 4.1 Overview
- 4.2 Analog Inputs
- 4.3 Analog Outputs
- 4.4 Analog In to Analog Out Passthrough
- 4.5 PWM Outputs
- 4.6 Serial Port Clocking
- 4.7 Digital Interface Formats
- 4.8 Initialization
- 4.9 Recommended Power-up Sequence
- 4.10 Recommended Power-Down Sequence
- 4.11 Required Initialization Settings
- 4.12 Control Port Operation
- 5. Register Quick Reference
- 6. Register Description
- 6.1 Chip I.D. and Revision Register (Address 01h) (Read Only)
- 6.2 Power Control 1 (Address 02h)
- 6.3 Power Control 2 (Address 03h)
- 6.4 Power Control 3 (Address 04h)
- 6.5 Clocking Control (Address 05h)
- 6.6 Interface Control 1 (Address 06h)
- 6.7 Interface Control 2 (Address 07h)
- 6.8 Input x Select: ADCA and PGAA (Address 08h), ADCB and PGAB (Address 09h)
- 6.9 Analog and HPF Control (Address 0Ah)
- 6.10 ADC HPF Corner Frequency (Address 0Bh)
- 6.11 Misc. ADC Control (Address 0Ch)
- 6.12 Playback Control 1 (Address 0Dh)
- 6.13 Miscellaneous Controls (Address 0Eh)
- 6.14 Playback Control 2 (Address 0Fh)
- 6.15 MICx Amp Control:MIC A (Address 10h) and MIC B (Address 11h)
- 6.16 PGAx Vol. and ALCx Transition Ctl.: ALC, PGA A (Address 12h) and ALC, PGA B (Address 13h)
- 6.17 Passthrough x Volume: PASSAVOL (Address 14h) and PASSBVOL (Address 15h)
- 6.18 ADCx Volume Control: ADCAVOL (Address 16h) and ADCBVOL (Address 17h)
- 6.19 ADCx Mixer Volume: ADCA (Address 18h) and ADCB (Address 19h)
- 6.20 PCMx Mixer Volume: PCMA (Address 1Ah) and PCMB (Address 1Bh)
- 6.21 Beep Frequency and On Time (Address 1Ch)
- 6.22 Beep Volume and Off Time (Address 1Dh)
- 6.23 Beep and Tone Configuration (Address 1Eh)
- 6.24 Tone Control (Address 1Fh)
- 6.25 Master Volume Control: MSTA (Address 20h) and MSTB (Address 21h)
- 6.26 Headphone Volume Control: HPA (Address 22h) and HPB (Address 23h)
- 6.27 Speaker Volume Control: SPKA (Address 24h) and SPKB (Address 25h)
- 6.28 ADC and PCM Channel Mixer (Address 26h)
- 6.29 Limiter Control 1, Min/Max Thresholds (Address 27h)
- 6.30 Limiter Control 2, Release Rate (Address 28h)
- 6.31 Limiter Attack Rate (Address 29h)
- 6.32 ALC Enable and Attack Rate (Address 2Ah)
- 6.33 ALC Release Rate (Address 2Bh)
- 6.34 ALC Threshold (Address 2Ch)
- 6.35 Noise Gate Control (Address 2Dh)
- 6.36 Status (Address 2Eh) (Read Only)
- 6.37 Battery Compensation (Address 2Fh)
- 6.38 VP Battery Level (Address 30h) (Read Only)
- 6.39 Speaker Status (Address 31h) (Read Only)
- 6.40 Charge Pump Frequency (Address 34h)
- 7. Analog Performance Plots
- 8. Example System Clock Frequencies
- 9. PCB Layout Considerations
- 10. ADC and DAC Digital Filters
- 11. Parameter Definitions
- 12. Package Dimensions
- 13. Ordering Information
- 14. References
- 15. Revision History

30 DS680F2
CS42L52
3/1/13
4.3.2 Limiter
When enabled, the limiter monitors the digital input signal before the DAC and PWM modulators, detects
when levels exceed the maximum threshold settings, and lowers the master volume at a programmable
attack rate below the maximum threshold. When the input signal level falls below the maximum threshold,
the AOUT volume returns to its original level set in the Master Volume Control register at a programmable
release rate. Attack and release rates are affected by the DAC soft-ramp/zero-cross settings and sample
rate, Fs. Limiter soft-ramp and zero-cross dependency may be independently enabled/disabled.
Notes:
1. Recommended settings: Best limiting performance may be realized with the fastest attack and
slowest release setting with soft ramp enabled in the control registers. The MIN bits allow the user to
set a threshold slightly below the maximum threshold for hysteresis control - this cushions the sound
as the limiter attacks and releases.
2. The Limiter maintains the output signal between the MIN and MAX thresholds. As the digital input
signal level changes, the level-controlled output may not always be the same but will always fall within
the thresholds.
Referenced Control Register Location
MSTxVOL[7:0].....................
PMIXxVOL[6:0] ...................
OFFTIME[2:0] .....................
ONTIME[3:0] .......................
FREQ[3:0] ...........................
BEEP[1:0]............................
BEEPMIXDIS ......................
BPVOL[4:0] .........................
“Master Volume Control: MSTA (Address 20h) and MSTB (Address 21h)” on page 63
“PCMx Mixer Volume: PCMA (Address 1Ah) and PCMB (Address 1Bh)” on page 58
“Beep Off Time” on page 60
“Beep On Time” on page 60
“Beep Frequency” on page 59
“Beep Configuration” on page 61
“Beep Mix Disable” on page 61
“Beep Volume” on page 61
Referenced Control Register Location
Limiter Controls...................
Master Volume Control........
“Limiter Control 2, Release Rate (Address 28h)” on page 66, “Limiter Attack Rate (Address 29h)” on page 67
“Master Volume Control: MSTA (Address 20h) and MSTB (Address 21h)” on page 63
FREQ[3:0]
...
BPVOL[4:0]
ONTIME[3:0] OFFTIME[2:0]
BEEP[1:0] =
'01'
BEEP[1:0] =
'10'
BEEP[1:0] =
'11'
SINGLE-BEEP: Beep turns on at a
configurable frequency (FREQ) and
volume (BPVOL) for the duration of
ONTIME. BEEP must be cleared
and set for additional beeps.
MULTI-BEEP: Beep turns on at a configurable frequency (FREQ)
and volume (BPVOL) for the duration of ONTIME and turns off for
the duration of OFFTIME. On and off cycles are repeated until
BEEP is cleared.
CONTINUOUS BEEP: Beep turns on at a configurable frequency (FREQ) and volume (BPVOL) and remains on
until BEEP is cleared.
Figure 13. Beep Configuration Options