Configuration Register

D23

D22

D21

D20

D19

D18

D17

D16

D15

D14

D13

D12

Register

DAC3

DAC2

DAC1

DAC0

EXC

F1

F0

D16

G1

G0

U/B

D12

Reset (R)

000000000000

D11

D10

D9

D8

D7

D6

D5

D4

D3

D2

D1

D0

Register

A/S

EC

D9

D8

CC3

CC2

CC1

CC0

D3

D2

D1

RF

Reset (R)

000000000000

BIT

NAME

VALUE

FUNCTION

DAC3

DAC Sign Bit

0

1

R

1

Add Offset

Subtract Offset

This bit is read only

2

DAC2-0

DAC Bits

000

001

010

011

100

101

110

111

R

25% Offset

50% Offset

75% Offset

100% Offset

These bits are read only

2

125% Offset

150% Offset

175% Offset

EXC

Excitation:

Internal

External

0

1

R

BX1 and BX2 outputs are determined by bits F1 and F0

BX1 is an input which determines the phase of the

demodulation clock and the BX2 output

F1-F0

Select Frequency

00

01

10

11

R

Excitation on BX1 & BX2 is dc. BX1=0 V, BX2=+5 V

Excitation Frequency on BX1 & BX2 is XIN/8192 Hz

Excitation Frequency on BX1 & BX2 is XIN/16384 Hz

Excitation Frequency on BX1 & BX2 is XIN/4096 Hz

D16

D16

0

R

Must always be logic 0

G1-G0

Select PGA Gain

00

10

01

11

R

Gain = 1 (X25)

Gain = 2 (X25)

Gain = 4 (X25)

Gain = 8 (X25)

U/B

Select Unipolar/Bipo-

lar Mode

0

1

R

Bipolar Measurement Mode

Unipolar Measurement Mode

D12

D12

0

R

Must always be logic 0

A/S

Awake/Sleep

0

1

R

Awake Mode

Sleep Mode

EC

Execute Calibration

0

1

R

Calibration not active

Perform calibration selected by CC3-CC0 bits. EC bit

must be written back to "0" after calibration is completed

D9

D9

0

R

Must always be logic 0

D8

D8

0

R

Must always be logic 0

CC3-CC0

Calibration Control Bits

0000

1000

0100

0010

0001

R

No calibration to be performed

Calibrate non-ratiometric offset, VREF

Calibrate non-ratiometric offset, AIN

Calibrate ratiometric offset, AIN

Calibrate gain, AIN

D3

D3

0

R

Must always be logic 0

D2

D2

0

R

Must always be logic 0

D1

D2

0

R

Must always be logic 0

RF

Reset Filter

0

1

R

Normal operation

Reset Filter

Notes: 1.Reset State

2.A write to these bits does not change the register bit values. These bits are just a mirror of the DAC register contents.

Table 2. Configuration Register

CS5516, CS5520

DS74F1

13

DS74F2

13