CS4461
Multi-Bit A/D for Class-D Real-Time PSR Feedback
Features
Advanced Multi-bit Delta-Sigma Architecture
Real-time Feedback of Power Supply
Conditions (AC and DC)
Filterless Digital Output Resulting in Very Low
Signal Delay
135 mW Power Consumption
Supports Logic Levels Between 3.3 V and
5.0 V
Differential Analog Architecture
Modulator Overflow Detection
Interfaces Directly to the CS44800/CS44600
Class-D PWM Modulator
Multi-bit Conversion at up to 7.5 MHz
Delivers Modulated Data Over 2-Wire Interface
General Description
The CS4461 is a complete analog-to-digital converter
for class-D real-time power supply rejection (PSR) feed-
back. It performs sampling and analog-to-digital
conversion, generating digital data for input to a
class-D modulator with real-time PSR feedback
capabilities.
The CS4461 uses a 5th-order, multi-bit delta-sigma
modulator followed by output data formatting. The ADC
uses a differential architecture which provides excellent
noise rejection.
The CS4461 feeds back the AC and DC voltage compo-
nents and is ideal for class-D audio systems requiring
high power supply rejection.
The CS4461 is available in a 24-pin TSSOP package in
both Commercial (-10° to +70° C) and Automotive
grade (-40° to +85° C). The CDB44800 Customer Dem-
onstration board is also available for device evaluation
and implementation suggestions. Please see
for complete details.
VQ
REFGND
PSR_RESET
PSR_EN
FILT+
Voltage Reference
OVERFLOW
AIN+
AIN-
+
LP Filter
PSR_MCLK
∆Σ
Output Data
Formatting
PSR_SYNC
PSR_DATA
S/H
-
DAC
5.0 V
(VA)
GND
3.3 V to 5.0 V
(VDP)
Copyright
©
Cirrus Logic, Inc. 2005
(All Rights Reserved)
SEPTEMBER '05
DS650F1
CIRRUS [ CIRRUS LOGIC ]
