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Cs4245, System features, General description – Cirrus Logic CS4245 User Manual

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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.