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
General Description
The CS4245 is a highly integrated stereo audio CO-
DEC. 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 selecting
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/attenuation
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 incorporates selectable soft ramp and zero
crossing transition functions to eliminate clicks and
pops.
Standard 50/15
µs
de-emphasis is available for a
44.1 kHz sample rate for compatibility with digital audio
programs mastered using the 50/15
µs
pre-emphasis
technique.
Integrated level translators allow easy interfacing be-
tween the CS4245 and other devices operating over a
wide range of logic levels.
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 control port interfaces
Pin-compatible with CS5345
ORDERING INFORMATION
CS4245-CQZ -10° to 70° C
CDB4245
48-pin LQFP
Evaluation Board
2
CIRRUS [ CIRRUS LOGIC ]
