PCM1770 Datasheet, PDF (26/29 Pages) Texas Instruments – LOW VOLTAGE AND POWER STEREO AUDIO DIGITAL TO ANALOG CONVER WITH HEADPHONE AMPLIFER

PCM1770
PCM1771
SLES011C – SEPTEMBER 2001 – REVISED MAY 2004
APPLICATION INFORMATION
www.ti.com
CONNECTION DIAGRAMS
Figure 29 shows the basic connection diagram with the necessary power supply bypassing and decoupling components.
It is recommended that the component values shown in Figure 29 be used for all designs.
The use of series resistors (22 Ω to 100 Ω) are recommended for the MCKI, LRCK, BCK, and DATA inputs. The series
resistor combines with the stray PCB and device input capacitance to form a low-pass filter that reduces high frequency
noise emissions and helps to dampen glitches and ringing present on the clock and data lines.
POWER SUPPLIES AND GROUNDING
The PCM1770 and PCM1771 devices require a 2.4-V typical analog supply for V_CC and V_HP. These 2.4-V supplies power
the DAC, analog output filter, and other circuits. For best performance, these 2.4-V supplies must be derived from the
analog supply using a linear regulator, as shown in Figure 29.
Figure 29 shows the proper power supply bypassing. The 10-µF capacitors must be tantalum or aluminum electrolytic,
while the 0.1-µF capacitors are ceramic (X7R type is recommended for surface-mount applications).
1.6 V to 3.6 V
Audio DSP
Controller
10 µF
1 LRCK
SCKI 16
2 DATA
MS 15
3 BCK
MC 14
4 PD
PCM1770
5 AGND
MD 13
VCC 12
6 HGND
VHP 11
7 VCOM
AIN 10
8 HOUTR
HOUTL 9
0.022 µF
16 Ω
10 µF
10 µF
10 µF
220 µF
Analog In
220 µF
Headphone
RL = 16 Ω
0.022 µF
16 Ω
Figure 29. Basic Connection Diagram
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