PCM1739 Datasheet, PDF (13/16 Pages) Burr-Brown (TI) – 24-Bit, 192kHz Sampling, Enhanced Multi-Level, Delta-Sigma, Audio DIGITAL-TO-ANALOG CONVERTER

APPLICATIONS INFORMATION
CONNECTION DIAGRAM
A basic connection diagram with the necessary power sup-
ply bypassing and decoupling components is shown in
Figure 8. Burr-Brown recommends using the component
values shown in Figure 8 for all designs.
The use of series resistors (22Ω to 100Ω) is recommended
for the SCLK, LRCK, BCLK, and DATA inputs. The series
resistor combines with the stray PCB and device input
capacitance to form a low-pass filter, which reduces high
frequency noise emissions and helps to dampen glitches and
ringing present on clock and data lines.
POWER SUPPLIES AND GROUNDING
The PCM1739 requires a +5V analog supply and a +3.3V
digital supply. The +5V supply is used to power the DAC
analog and output filter circuitry, while the +3.3V supply is
used to power the digital filter and logic circuitry. For best
performance, the +3.3V supply should be derived from the
+5V supply using a linear regulator, shown in Figure 8.
Burr-Brown’s REG1117-3.3 is an ideal choice for this appli-
cation.
Proper power supply bypassing is shown in Figure 8. The
bypass capacitors should be located as close as possible to
the PCM1739 package. The 1µF and 10µF capacitors should
be tantalum or aluminum electrolytic, while the 0.1µF ca-
pacitors are ceramic (X7R type is recommended for surface
mount applications).
D/A OUTPUT CIRCUITS
Delta-sigma D/A converters utilize noise-shaping techniques
to improve in-band Signal-to-Noise (SNR) performance at
the expense of generating increased out-of-band noise above
the Nyquist Frequency, or f_S/2. The out-of-band noise must
be low-pass filtered in order to provide optimal converter
performance. This is accomplished by a combination of on-
chip and external low pass filtering.
Figures 7a and 9 show the recommended external low pass
active filter circuits for dual and single-supply applications.
These circuits are 2nd-order filters using the Multiple Feed-
back (MFB) circuit arrangement, which reduces sensitivity to
passive component variations over frequency and tempera-
ture. For more information regarding MFB active filter design,
please refer to Burr-Brown Applications Bulletin AB-034.
From/To
Audio
Source
From
Mode Control
Logic
R_S(1)
PCM1739
LRCK
FORM
DATA
DEM1
BCLK
DEM0
CLKO
NC
SCLK
ZEROR
+ ^C1
V_SS
C₂
V_DD
TEST1
ZEROL
RSTB
MUTE
IBIT
FILT
+
C₃
+ ^C4
V_CCR
GNDR
V_COMR
V_OUTR
GNDA
V_CCL
GNDL
V_COML
V_OUTL
V_CCA
+3.3V
C₅
Regulator
C₆
+
From
Mode Control
Logic
Zero Flag
Outputs
From Host Or
Master Reset
From
Mode Control
Logic
+
C₁₀
+ ^C9
+
C₈
To
Output
Filter
Circuits
+5V
Analog
C₇
+
C₁, C₄, C₆, C₉ = 10µF Tantalum or Aluminum Electrolytic
C₂, C₅ = 0.1µF Ceramic
C₃, C₁₀ = 1µF Tanatlum or Aluminum Electrolytic
C₇, C₈ = 1-10µF Aluminum Electrolytic
NOTE: (1) R_S = 20Ω to 100Ω.
FIGURE 8. Basic Connection Diagram.
13
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PCM1739