CS5525 CS5526

24

DS202F5

PIN DESCRIPTIONS

Clock Generator

XIN; XOUT - Crystal In; Crystal Out, Pins 9, 10.

A gate inside the chip is connected to these pins and can be used with a crystal to provide the

master clock for the device. Alternatively, an external (CMOS compatible) clock can be

supplied into the XIN pin to provide the master clock for the device.

Control Pins and Serial Data I/O

CS - Chip Select, Pin 18.

When active low, the port will recognize SCLK. When high the SDO pin will output a high

impedance state. CS should be changed when SCLK = 0.

SDI - Serial Data Input, Pin 17.

SDI is the input pin of the serial input port. Data will be input at a rate determined by SCLK.

SDO - Serial Data Output, Pin 14.

SDO is the serial data output. It will output a high impedance state if CS = 1.

SCLK - Serial Clock Input, Pin 11.

A clock signal on this pin determines the input/output rate of the data for the SDI/SDO pins

respectively. This input is a Schmitt trigger to allow for slow rise time signals. The SCLK pin

will recognize clocks only when CS is low.

A0, A1, A2, A3 - Logic Outputs, Pin 6, 7, 15, 16.

The logic states of A0-A3 mimic the states of the D20-D23 bits of the configuration register.

Logic Output 0 = AGND, and Logic Output 1 = VA+.

1

2

3

4

5

6

7

8

9

20

19

18

17

16

15

14

13

12

10

11

ANALOG GROUND

AGND

VREF+ VOLTAGE REFERENCE INPUT

POSITIVE ANALOG POWER

VA+

VREF- VOLTAGE REFERENCE INPUT

DIFFERENTIAL ANALOG INPUT

AIN+

CS

CHIP SELECT

DIFFERENTIAL ANALOG INPUT

AIN-

SDI

SERIAL DATA INPUT

NEGATIVE BIAS VOLTAGE

NBV

A3

LOGIC OUTPUT

LOGIC OUTPUT

A0

A2

LOGIC OUTPUT

LOGIC OUTPUT

A1

SDO

SERIAL DATA OUTPUT

CHARGE PUMP DRIVE

CPD

VD+

POSITIVE DIGITAL POWER

CRYSTAL IN

XIN

DGND DIGITAL GROUND

CRYSTAL OUT

XOUT

SCLK SERIAL CLOCK INPUT