32

LTC2420

Table 6. Typical Performance of the LTC2420 ADC When Used with the

LT1167 Instrumentation Amplifiers in Figure 34’s Differential Digitizing Circuit

PARAMETER

TOTAL (UNITS)

Differential Input Voltage Range

– 30 to 400

– 3 to 40

– 30 to 500

– 3 to 50

mV

Zero Error

–94

– 1590

– 110

– 1470

µV

Maximum Input Current

0.5

nA

Nonlinearity

±4.1

±4.4

±4.1

±3.7

ppm

Noise (Without Averaging)

1.4*

0.19*

1.5*

0.18*

Noise (Averaged 64 Readings)

0.18*

0.02*

0.19*

0.02*

Resolution (with Averaged Readings)

21.4

21.0

21.3

21.1

Bits

Overall Accuracy (Uncalibrated)

18.2

18.1

18.2

19.4

Bits

Common Mode Rejection Ratio

≥120

dB

Common Mode Range

2/–1.5**

2.2/–1.7**

11.5/–11**

11.7/–11.2**

V

*Input referred noise for the respective gain. **Typical values based on single lab tested sample of each amplifier.

TYPICAL APPLICATIO S

Table 5. Typical Performance of the LTC2420 ADC When Used with the

LT1920 Instrumentation Amplifiers in Figure 34’s Differential Digitizing Circuit

PARAMETER

TOTAL (UNITS)

Differential Input Voltage Range

– 30 to 400

– 3 to 40

– 30 to 500

– 3 to 50

mV

Zero Error

–160

– 2650

– 213

– 2625

µV

Maximum Input Current

2.0

nA

Nonlinearity

±8.2

±7.4

±6.5

±6.1

ppm

Noise (Without Averaging)

1.8*

0.25*

1.5*

0.27*

Noise (Averaged 64 Readings)

0.2*

0.03*

0.19*

0.03*

Resolution (with Averaged Readings)

21

20.6

21.3

20.5

Bits

Overall Accuracy (Uncalibrated)

17.2

17.3

17.5

18.2

Bits

Common Mode Rejection Ratio

≥120

dB

Common Mode Range

2/–1.5**

2.2/–1.7**

11.5/–11**

11.7/–11.2**

V

*Input referred noise for the respective gain. **Typical values based on single lab tested sample of each amplifier.