CS5320/21/22

DS454PP1

33

DECC - Decimation Rate Control, Pin 16

See Table 4.

H/S - Hardware/Software Mode Select, Pin 13

When high, the device pins control device operation; when low, the value entered by a prior

configuration write controls device operation.

CS - Chip Select, Pin 1

When high, all signal activity on the SID, R/W and SCLK pins is ignored. The DRDY and

ERROR signals indicate the status of the chip’s internal operation.

R/W - Read/Write, Pin 28

Used in conjunction with CS such that when both signals are low, the filter inputs data from the

SID pin on the falling edge of SCLK. If CS is low and R/W is high, the filter outputs data on

the SOD pin on the rising edge of SCLK. R/W low floats the SOD pin allowing SID and SOD

to be tied together, forming a bidirectional serial data bus.

SCLK - Serial Clock, Pin 26

Clock signal generated by host processor to either input data on the SID input pin, or output

data on the SOD output pin. For write, data must be valid on the SID pin on the falling edge of

SCLK. Data changes on the SOD pin on the rising edge of SCLK.

SID - Serial Data Input, Pin 25

Data bits are presented MSB first, LSB last. Data is latched on the falling edge of SCLK.

RSEL - Register Select, Pin 27

Selects conversion data when high, or status data when low.

USEOR - Use Offset Register, Pin 15

Use offset register value to correct output words when high. Output words will not be offset

corrected when low.

ORCAL - Offset Register Calibrate, Pin 19

Initiates an offset calibration cycle when SYNC goes high after ORCAL has been toggled from

low to high. The offset value is output on the 57th word following SYNC. Subsequent words

will have their offset correction controlled by USEOR.