Datasheet

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SBAS342B − DECEMBER 2004 − REVISED APRIL 2006
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10
PRODUCT OVERVIEW
The PCM4202 is a single channel audio analog-to-digital
converter (ADC) designed for use in low power, battery-
operated or portable professional audio equipment. Target
applications include digital wireless microphones and
portable digital audio recorders/processors. The
PCM4201 features 24-bit linear PCM output data, with a
format compatible with digital signal processors, digital
audio interface transmitters, and programmable logic
devices.
The PCM4201 includes three sampling modes, supporting
sampling rates up to 108kHz. The Normal Speed, Low
Power mode supports sampling rates up to 54kHz, and
employs 64x oversampling to reduce overall converter
power. The Normal Speed, High Performance mode
supports sampling rates up to 54kHz with 128x
oversampling, resulting in improved dynamic range and
THD+N when compared to the Low Power mode, at the
expense of increased power dissipation. The Double
Speed mode supports sampling frequencies up to 108kHz
and is provided for those applications where higher
sampling rates may be required.
A digital high-pass filter is included for DC removal.
Dedicated control pins are included for sampling mode
selection, Slave/Master mode audio serial port operation,
digital high-pass filter enable/disable, and reset/
power-down functions.
A +5V power supply is required for the analog section of
the device, while a +3.3V power supply is typically utilized
for the digital section. The digital supply may be operated
at voltages as low as +1.8V, with a corresponding 10 to 20
milliwatt (mW) reduction in power dissipation, depending
upon the sampling mode selection. Figure 1 shows the
functional block diagram for the PCM4201.
HPF
Delta−Sigma
Modulator
Decimation
Filter
Voltage
Reference
V
REF
+
V
REF
−
V
IN
R+
V
IN
R
−
Power
V
DD
AGND
Reset
Logic
Clock
Control
Audio
Serial
Port
DGND
V
CC
FSYNC
BCK
DATA
S/M
RATE
SCKI
RST
HPFD
Figure 1. PCM4201 Functional Block Diagram