PCM3008

SLAS332 – APRIL 2001

13

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TYPICAL CHARACTERISTICS

typical circuit connection

The following figure illustrates a typical PCM3008 circuit connection.

VCOM

VINR

VINL

GND

VCC

DEM0

DEM1

DOUT

VOUTR

VOUTL

PDDA

PDAD

BCK

SYSCK

LRCK

DIN

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

+

+

+

Right Channel IN

Left Channel IN

C1(see Note A)

A/D IN

C2(see Note B)

C3(see Note B)

+

C4(see Note C)

2.4 V

De-Emp0

De-Emp1

Control

+

+

C6

(see Note D)

C5

(see Note D)

POST

LPF

(see Note E)

POST

LPF

(see Note E)

Right

Channel OUT

Left

Channel OUT

D/A OUT

D/A ON/OFF

A/D ON/OFF

Bit Clock

System Clock

L/R Clock

D/A IN

A/D OUT

Digital IN/OUT

2.4 V

PDDA

PDAD

(see Note F)

PCM3008

NOTES: A. C1: 0.1 µF ceramic and 1 µF chemical typical, gives settling time with 15 ms (1 µF × 15 kΩ) time constant in power on period.

B. C2, C3: 0.47 µF typical, gives 11 Hz cutoff frequency of input HPF in normal operation and gives settling time with 14 ms

(0.47

µF × 30 kΩ) time constant in power on and power down off period.

C. C4: 0.1 µF ceramic and 10 µF chemical typical, depending on power supply quality and pattern layout.

D. C5, C6: 1 µF typical, gives 16 Hz cut-off frequency of output HPF in normal operation and gives settling time with 10 ms (1 µF × 10 kΩ)

time constant in power on period.

E. Post low pass filter with RIN > 10 kΩ, depending on requirement of system performance.

F. Power on reset circuit in case of no power-down control requirement.

board design and layout considerations

The analog and digital power supply lines are internally tied, and the analog and digital grounds are internally

and 10

µF chemical capacitors as close to the pins as possible to maximize the dynamic performance of ADC

and DAC.

A chemical capacitor from 0.47

µF to 4.7 µF is recommended as an ac coupling capacitor. Capacitance of 0.47

µF gives 11 Hz cut-off frequency at input HPF. If higher full scale input voltage is required, it can be adjusted

A 0.1

low source impedance of ADC and DAC common voltage. This capacitor should be located as close as possible