User Manual
2 DS656F3
CS4245
System Features
Direct Interface with 1.8 V to 5 V Logic Levels
Optional Asynchronous Serial Port Operation
– Each Serial Port Supports Master or Slave
Operation
Selectable Auxiliary Analog Output
– Allows Analog Monitoring of Either the ADC
Input Signal after PGA or DAC Output
Signal
Internal Digital Loopback
Power-Down Mode
– Available for A/D, D/A, CODEC, Mic
Preamplifier
+3.3 V to +5 V Analog Power Supply
+3.3 V to +5 V Digital Power Supply
Supports I²C
®
and SPI
TM
Control Port
Interfaces
Pin-Compatible with CS5345
General Description
The CS4245 is a h ighly integrated stereo audio
CODEC. The CS4245 performs stereo analog-to-digital
(A/D) and digital-to-analog (D/A) conversion of up to
24-bit serial values at sample rates up to 192 kHz.
A 6:1 stereo input multiplexer is included for s electing
between line-level or microphone-level inputs. The mi-
crophone input path includes a +32 dB gain stage and
a low-noise bias voltage supply. The PGA is available
for line or microphone inputs and provides gain/attenu-
ation of 12 dB in 0.5 dB steps.
The output of the PGA is followed by an advanced 5th-
order, multi-bit delta sigma modulator and digital filter-
ing/decimation. Sampled data is transmitted by the
serial audio interface at rates from 4 kHz to 192 kHz in
either Slave or Master Mode.
The D/A converter is based on a 4th-order multi-bit delta
sigma modulator with an ultra-linear low-pass filter and
offers a volume control that operates with a 0.5 dB step
size. It in corporates selectable soft ramp and zero
crossing transition functions to eliminate clicks and
pops.
Standard 50/15 s de-emphasis is availa ble for a
44.1 kHz sample rate for compatibility with digital audio
programs mastered using the 50 /15 s pre-emphasis
technique.
Integrated level translators allow ea sy interfacing be-
tween the CS4245 and other devices operating over a
wide range of logic levels.
The CS4245 is available in a 48-pin LQFP package in
both Commercial (-10° to +70° C) and Automotive (-40°
to +105° C) grade. The CDB4245 Customer Demon-
stration board is also available for device evaluation and
implementation suggestions. Please see “Ordering In-
formation” on page 58 for complete details.