ZSSC3154 Datasheet

© 2016 Integrated Device Technology, Inc.

16

January 22, 2016

2.8

Analog Front End

The analog front-end (AFE) consists of the multiplexer (MUX), the programmable gain amplifier (PGA), and the

analog-to-digital converter (ADC).

2.8.1

Programmable Gain Amplifier

Table 2.1 shows the adjustable gains, the corresponding sensor signal input spans, and the common mode range

limits.

Table 2.1

Adjustable Gains and Resulting Sensor Signal Spans and Common Mode Ranges

PGA Gain

Maximum Input Span

1)

Input Common Mode Range

2)

XZC = Off

XZC = On

420

1.8

29 to 65

45 to 55

280

2.7

29 to 65

45 to 55

210

3.6

29 to 65

45 to 55

140

5.4

29 to 65

45 to 55

105

7.1

29 to 65

45 to 55

70

10.7

29 to 65

45 to 55

52.5

14.3

29 to 65

45 to 55

35

21.4

29 to 65

45 to 55

26.3

28.5

29 to 65

45 to 55

14

53.75

29 to 65

45 to 55

9.3

80

29 to 65

45 to 55

7

107

29 to 65

45 to 55

2.8

267

32 to 57

Not applicable

1)

Recommended maximum internal signal range is 80% of supply voltage.

2)

Refer to section 2.8.2 for an explanation of the analog offset compensation.

Recommendation: To achieve the best stability and linearity performance of the AFE, operate the PGA in a

selected to guarantee this constraint for the entire operating temperature range of the application and for the

specified sensor bridge tolerances.