®

4

PCM3500

PIN CONFIGURATION

Top View

SSOP

PIN

NAME

I/O

DESCRIPTION

1VCOM

OUT

Common-Mode Voltage (0.5VCC). This pin should be connected to ground through a capacitor.

2VREF1

—

Decouple Pin for Reference Voltage 1 (0.99VCC). This pin should be connected to ground through a capacitor.

3VREF2

—

Decouple Pin for Reference Voltage 2 (0.2VCC). This pin should be connected to ground through a capacitor.

4VIN

IN

Analog Input for the ADC.

5

AGND

—

Analog Ground for the ADC Input Signal.

6

M/S

IN

Master/Slave Select. This pin is used to determine the operating mode for the serial interface. A logic ‘0’ on this pin selects the Slave

Mode. A logic ‘1’ on this pin selects the Master Mode.(2)

7

TSC

IN

Time Slot Mode Control. This pin is used to select the time slot operating mode. A logic ‘0’ on this pin disables Time Slot Mode. A

logic ‘1’ on this pin enables Time Slot Mode.(2)

8

BCK

I/O

Bit Clock. This pin serves as the bit (or shift) clock for the serial interface. This pin is an input in Slave Mode and an output in Master

Mode.(1)

9

FS

I/O

Frame Sync. This pin serves as the frame synchronization clock for the serial interface. This pin is an input in Slave Mode and an

output in Master Mode.(1)

10

DIN

IN

Serial Data Input. This pin is used to write 16-bit data to the DAC.(1)

11

DOUT

OUT

Serial Data Output. The ADC outputs 16-bit data on this pin.(3)

12

FSO

OUT

Frame Sync Output. Active only when Time Slot Mode is enabled. This pin is set to a high impedance state when Time Slot mode

is disabled (TSC = 0).

13

VDD

—

Digital Power Supply. Used to power the digital section of the ADC and DAC, as well as the serial interface and mode control logic.

This pin is not internally connected to VCC.

14

DGND

—

Digital Ground. Internally connected through the substrate to analog ground.

15

SCKIO

I/O

System Clock Input/Output. This pin is a system clock output when using the crystal oscillator or XTI as the system clock input; when

XTI is connected to ground, this pin is a system clock input.(1)

16

XTO

OUT

Crystal Oscillator Output.

17

XTI

IN

Crystal Oscillator Input or an External System Clock Input.

18

HPFD

IN

High-Pass Filter Disable. When this pin is set to a logic ‘1’, the HPF function in the ADC is disabled.(2)

19

LOOP

IN

ADC-to-DAC Loop-Back Control. When this pin is set to logic ‘1’, the ADC data is fed to the DAC input.(2)

20

PDWN

IN

Power Down and Reset Control. When this pin is logic ‘0’, Power-Down Mode is enabled. The PCM3500 is reset on the rising edge

of this signal.(2)

21

AGND

—

Analog Ground for the DAC Output Signal.

22

VOUT

OUT

Analog Output from the DAC Output Filter.

23

AGND

—

Analog Ground. This is the ground for the internal analog circuitry.

24

VCC

—

Analog Power Supply. Used to power the analog circuitry of the ADC and DAC.

NOTES: (1) Schmitt-Trigger input. (2) Schmitt-Trigger input with an internal pull-down resistor. (3) Tri-state output in Time Slot Mode.

PIN ASSIGNMENTS

V

COM

V

REF1

V

REF2

V

IN

AGND

M/S

TSC

BCK

FS

DIN

DOUT

FSO

V

CC

AGND

V

OUT

AGND

PDWN

LOOP

HPFD

XTI

XTO

SCKIO

DGND

V

DD

1

2

3

4

5

6

7

8

9

10

11

12

24

23

22

21

20

19

18

17

16

15

14

13

PCM3500