CS4811GTR-01 View Datasheet(PDF) - Cirrus Logic
Part Name
Description
MFG CO.
CS4811GTR-01 Datasheet PDF : 24 Pages
| |||
CS4811
3. FUNCTIONAL DESCRIPTION
3.1 Overview
The CS4811 is a complete audio subsystem on a
chip, integrating a proprietary 24-bit audio process-
ing engine with large on chip RAM memories and
a single channel 24-bit audio codec.
The delta-sigma ADC includes linear phase digital
anti-aliasing filters and only requires a single-pole
external passive filter.
The sigma-delta DAC includes a switched-capaci-
tor anti-image filter and requires an external 2nd or
3rd order active filter that can be easily integrated
into the output differential-to-single-ended con-
verter circuit.
The serial control port is designed to accommodate
I2C® or SPI interfaces for stand-alone operation
with an external non-volatile memory.
3.2 Analog Inputs
3.2.1 Line Level Inputs
AIN+ and AIN- are the differential line level ana-
log inputs (See Figure 3). These pins are internally
biased to the CMOUT voltage of 2.3 V. A DC
blocking capacitor placed in series with the input
pins allows signals centered around 0 V to be input
to the CS4811. Figure 3 shows operation with a
single-ended input source. This source may be sup-
plied to either the positive or negative input as long
as the unused input is connected to ground through
capacitors as shown. When operated with single-
ended inputs, distortion will increase at input levels
higher than -1 dB Full Scale. If better performance
is required, a single-ended-to-differential convert-
er, shown in Figure 6, may be used. This circuit
provides unity gain, DC blocking on the input and
anti-alias filtering.
The OVL output pin asserts when the analog input
is out-of-range.
3.2.2 Digital High Pass Filter
In DC coupled systems, a small DC offset may ex-
ist between the input circuitry and the A/D con-
verters. The CS4811 includes a high pass filter
after the decimator to remove these DC compo-
nents. The high pass filter response, given in High
Pass Filter Characteristics, scales linearly with
sample rate. Thus, the -3 dB frequency at a
44.1 kHz sample rate will be equal to 44.1/48 times
that at a sample rate of 48 kHz.
4.7 k
10 µF
10 k
input signal
-
150
(2 Vrms max) +
+
10 k
10 k
-
CMOUT +
from
CS4811
+5 V
-
150
Buffered
CMOUT
+
10 µf
+
GND
0.1 µF
AIN -
2.2 nf
AIN +
Figure 6. Optional Line Input Buffer
12
DS486PP2
Share Link: 