CS4385
114 dB, 192 kHz 8-Channel D/A Converter
Features Description
The CS4385 is a complete 8-channel digital-to-analog
Advanced Multi-bit Delta Sigma Architecture
system. This D/A system includes digital de-emphasis,
24-bit Conversion
half-dB step size volume control, ATAPI channel mix-
ing, selectable fast and slow digital interpolation filters
Automatic Detection of Sample Rates up to
followed by an oversampled, multi-bit delta sigma mod-
192 kHz
ulator which includes mismatch-shaping technology
that eliminates distortion due to capacitor mismatch.
114 dB Dynamic Range
Following this stage is a multi-element switched capac-
itor stage and low-pass filter with differential analog
-100 dB THD+N
outputs.
Direct Stream Digital Mode
The CS4385 also has a proprietary DSD processor
Non-Decimating Volume Control
which allows for volume control and 50 kHz on-chip fil-
tering without an intermediate decimation stage. It also
On-Chip 50 kHz Filter
offers an optional path for direct DSD conversion by di-
Matched PCM and DSD Analog Output
rectly using the multi-element switched capacitor array.
Levels
The CS4385 is available in a 48-pin LQFP package in
Compatible with Industry-Standard Time
both Commercial (-40C to +85C) and Automotive
Division Multiplexed (TDM) Serial Interface
(-40C to +105C) grades. The CDB4385 Customer
Selectable Digital Filters
Demonstration board is also available for device evalu-
ation and implementation suggestions. Please see
Volume Control with 1/2-dB Step Size and Soft
Ordering Information on page 54 for complete details.
Ramp
The CS4385 accepts PCM data at sample rates from
Low Clock-Jitter Sensitivity
4 kHz to 216 kHz, DSD audio data, and delivers excel-
lent sound quality. These features are ideal for multi-
+5 V Analog Supply, +2.5 V Digital Supply
channel audio systems, including SACD players, A/V
receivers, digital TVs, mixing consoles, effects proces-
Separate 1.8 to 5 V Logic Supplies for the
sors, sound cards, and automotive audio systems.
Control and Serial Ports
Control Port Supply = 1.8 V to 5 V Digital Supply = 2.5 V Analog Supply = 5 V
Hardware Mode or
2
I C/SPI Software Mode
Control Data
Internal Voltage
Register/Hardware
Reference
Configuration
Reset
Serial Audio Port
Supply = 1.8 V to 5 V
Eight Channels
Switch-Cap
8
Volume
Digital Multi-bit
of Differential
DAC and
PCM Serial
8 Controls
Filters Modulators
Outputs
Analog Filters
Audio Input
8
TDM Serial
Audio Input
DSD Processor External Mute
Mute Signals
Control
-Volume control
2
DSD Audio
-50 kHz filter
Input
Copyright Cirrus Logic, Inc. 2008 FEB '08
(All Rights Reserved)
CS4385
TABLE OF CONTENTS
1. PIN DESCRIPTION ...................................................................................................................... 6
2. CHARACTERISTICS AND SPECIFICATIONS ...................................................................................... 8
RECOMMENDED OPERATING CONDITIONS ..................................................................................... 8
ABSOLUTE MAXIMUM RATINGS ......................................................................................................... 8
DAC ANALOG CHARACTERISTICS - COMMERCIAL (-CQZ) ............................................................. 9
DAC ANALOG CHARACTERISTICS - AUTOMOTIVE (-DQZ) ............................................................ 10
POWER AND THERMAL CHARACTERISTICS .................................................................................. 11
COMBINED INTERPOLATION & ON-CHIP ANALOG FILTER RESPONSE ...................................... 12
COMBINED INTERPOLATION & ON-CHIP ANALOG FILTER RESPONSE (CONTINUED) .............. 13
DSD COMBINED DIGITAL & ON-CHIP ANALOG FILTER RESPONSE ............................................. 13
DIGITAL CHARACTERISTICS ............................................................................................................. 14
SWITCHING CHARACTERISTICS - PCM ........................................................................................... 15
SWITCHING CHARACTERISTICS - DSD ........................................................................................... 16
SWITCHING CHARACTERISTICS - CONTROL PORT - IC FORMAT .............................................. 17
SWITCHING CHARACTERISTICS - CONTROL PORT - SPI FORMAT ............................................. 18
3. TYPICAL CONNECTION DIAGRAM ................................................................................................... 19
4. APPLICATIONS ................................................................................................................................... 21
4.1 Master Clock ................................................................................................................................... 21
4.2 Mode Select .................................................................................................................................... 22
4.3 Digital Interface Formats ................................................................................................................ 23
4.3.1 OLM #1 .................................................................................................................................. 24
4.3.2 OLM #2 .................................................................................................................................. 24
4.3.3 OLM #3 .................................................................................................................................. 25
4.3.4 OLM #4 .................................................................................................................................. 25
4.3.5 TDM ....................................................................................................................................... 26
4.4 Oversampling Modes ...................................................................................................................... 26
4.5 Interpolation Filter ........................................................................................................................... 26
4.6 De-Emphasis .................................................................................................................................. 27
4.7 ATAPI Specification ........................................................................................................................ 27
4.8 Direct Stream Digital (DSD) Mode .................................................................................................. 28
4.9 Grounding and Power Supply Arrangements ................................................................................. 29
4.9.1 Capacitor Placement ............................................................................................................. 29
4.10 Analog Output and Filtering .......................................................................................................... 29
4.11 The MUTEC Outputs .................................................................................................................... 30
4.12 Recommended Power-Up Sequence ........................................................................................... 31
4.12.1 Hardware Mode ................................................................................................................... 31
4.12.2 Software Mode .................................................................................................................... 32
4.13 Recommended Procedure for Switching Operational Modes ....................................................... 32
4.14 Control Port Interface ................................................................................................................... 32
4.14.1 MAP Auto Increment ........................................................................................................... 32
4.14.2 IC Mode .............................................................................................................................. 32
4.14.2.1 IC Write ................................................................................................................... 33
4.14.2.2 IC Read .................................................................................................................. 33
4.14.3 SPI Mode ............................................................................................................................. 34
4.14.3.1 SPI Write .................................................................................................................. 34
4.15 Memory Address Pointer (MAP) .................................................................................................. 34
4.15.1 INCR (Auto Map Increment Enable) .................................................................................... 34
4.15.2 MAP4-0 (Memory Address Pointer) .................................................................................... 34
5. REGISTER QUICK REFERENCE ....................................................................................................... 35
6. REGISTER DESCRIPTION .................................................................................................................. 37
6.1 Chip Revision (address 01h) ......................................................................................................... 37
6.1.1 Part Number ID (PART) [Read Only] .................................................................................... 37
2 DS671F2