PCM1794A Datasheet, PDF (25/34 Pages) Burr-Brown (TI) – 24-bit,192-khz sampling,advanced segment, audio stereo digital-to-analog converter

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PCM1794A
SLES117B – AUGUST 2004 – REVISED DECEMBER 2015
8.2 Typical Application
This application is using the GPIO of a host controller to manipulate the hardware control pins. A PCM audio
source is supplying digital audio and the output is single-ended stereo audio.
Controller
PCM
Audio Data
Source
Controller
0.1 µF
1 MONO
VCC2L 28
2 CHSL
AGND3L 27
3 DEM
IOUTL– 26
4 LRCK
IOUTL+ 25
5 DATA
AGND2 24
6 BCK
VCC1 23
7 SCK
VCOML 22
PCM1794A
8 DGND
VCOMR 21
9 VDD
10 MUTE
IREF 20
AGND1 19
11 FMT0
IOUTR– 18
12 FMT1
IOUTR+ 17
13 ZERO
AGND3R 16
14 RST
VCC2R 15
3.3 V
+
5V
0.1 µF
+ ^{10 µF}
5V
+ ^{47 µF}
+ 10 µF
+
47 µF
10 kΩ
0.1 µF
5V
+ ^{10 µF}
Cf
Rf
–
+
Cf
Rf
–
+
Cf
Rf
–
+
Cf
Rf
–
+
Differential
to
Single
Converter
With
Low-Pass
Filter
VOUT
L-Channel
Differential
to
Single
Converter
With
Low-Pass
Filter
VOUT
R-Channel
10 µF
Figure 31. Typical Application Circuit
8.2.1 Design Requirements
For the typical application example, use the parameters listed in Table 6.
DESIGN PARAMETER
Audio Input
Audio Output
Control
Filter
Table 6. Design Parameters
EXAMPLE
Digital PCM
Single-Ended Stereo Analog
Host GPIO
Internal Filter
8.2.2 Detailed Design Procedure
8.2.2.1 Audio Input or Output
In this application, a PCM audio source is supplied to the device. A current output is produced and then
converted to a voltage output in the I/V stage. The next stage in the output is a differential to single-ended
amplifier stage with a low pass filter to reduce out of band noise. The f_c of the example circuits (Figure 26 and
Figure 27) are shown in the example figures. Use Equation 2 to calculate the value of f_c.
f_c = 1 / (2 × π × R_f × C_f)
(2)
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