Low-Cost Precision Sensor

Signal Conditioner

22

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Table 14. ALOC Definition

ALOC[3:0]

ANALOG SIGNAL

DESCRIPTION

0000

OUT

PGA Output

0001

BDR

Bridge Drive

0010

ISRC

Bridge Drive Current Setting

0011

VDD

Internal Positive Supply

0100

VSS

Internal Ground

0101

BIAS5U

Internal Test Node

0110

AGND

Internal Analog Ground. Approximately half of VDD.

0111

FSODAC

Full Scale Output DAC

1000

FSOTCDAC

Full Scale Output TC DAC

1001

ODAC

Offset DAC

1010

OTCDAC

Offset TC DAC

1011

VREF

Bandgap Reference Voltage (nominally 1.25V)

1100

VPTATP

Internal Test Node

1101

VPTATM

Internal Test Node

1110

INP

Sensor’s Positive Input

1111

INM

Sensor’s Negative Input

Table 15. Effects of Compensation

TYPICAL UNCOMPENSATED INPUT (SENSOR)

TYPICAL COMPENSATED TRANSDUCER OUTPUT

Offset…………………..…….…………………………..

±100%FSO

FSO…………………………….………………………..1 to 40mV/V

Offset TC…………………………………………………...20% FSO

Offset TC Nonlinearity…..………………………………….4% FSO

FSOTC…………………………..………………………..-20% FSO

FSOTC Nonlinearity…..……..…………………………….5% FSO

Temperature Range..….….……………………..-40

°C to +125°C

OUT..…….……………………………..Ratiometric to VDD at 5.0V

Offset at +25

°C……………………………………0.500V ± 200µV

FSO at +25

°C……………………………………...4.000V ± 200µV

Offset accuracy over temp. range….………

±4mV (±0.1% FSO)

FSO accuracy over temp. range……………

±4mV (±0.1% FSO)

Chip Information

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