CS5531-AS datasheet(47/52 Pages) CIRRUS

47 / 52 page

CS5531/32/33/34

DS289PP5

SDI - Serial Data Input.

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

SDO - Serial Data Output.

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

SCLK - Serial Clock Input.

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 - Logic Output (Analog)/Guard, A1 - Logic Output (Analog).

The logic states of A1-A0 mimic the OL1-OL0 bits in the selected Setup, or the A1-A0 bits in

the Configuration Register, depending on the state of the OLS bit in the Configuration Register.

Logic Output 0 = VA-, and Logic Output 1 = VA+. Alternately, A0 can be used as a guard

drive for the instrumentation amplifier with proper setting of the GB bit in the Configuration

Measurement and Reference Inputs

AIN1+, AIN1-, AIN2+, AIN2- AIN3+, AIN3-, AIN4+, AIN4- - Differential Analog Input.

Differential input pins into the device.

VREF+, VREF- - Voltage Reference Input.

Fully differential inputs which establish the voltage reference for the on-chip modulator.

C1, C2 - Amplifier Capacitor Inputs.

Connections for the instrumentation amplifier’s capacitor.

Power Supply Connections

VA+ - Positive Analog Power.

Positive analog supply voltage.

VD+ - Positive Digital Power.

Positive digital supply voltage (nominally +3.0 V or +5 V).

VA- - Negative Analog Power.

Negative analog supply voltage.

DGND - Digital Ground.

Digital Ground.

CS5531-AS Datasheet(PDF) 47 Page - Cirrus Logic