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National Instruments 24-Bit Half/Full-Bridge Analog Input Module NI 9237 User Manual

Page 25

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© National Instruments Corp.

25

NI 9237 Operating Instructions and Specifications

Rejection at oversample rate

1

f

s

= 10 kS/s.................................. 60 dB @ 640 kHz

f

s

= 50 kS/s.................................. 90 dB @ 3.2 MHz

Common-mode voltage,
all signals to earth ground................. ±60 VDC

CMRR

Relative to earth ground

2

(f

in

= 0 to 60 Hz) ......................... 140 dB

Relative to EX–
(f

in

= 0 to 1 kHz) ......................... 85 dB

SFDR (1 kHz, –60 dBFS)................. 106 dB

Total Harmonic Distortion (THD)

1 kHz, –20 dBFS ........................ 100 dB
8 kHz, –20 dBFS ........................ 90 dB

1

Rejection by analog prefilter of signal frequencies at oversample rate.

2

Measured with a balanced cable. Shielded cables that are not twisted-pair may be

significantly unbalanced. To improve the balance of shielded, twisted-pair cables,
NI recommends twisting together the AI+/AI

pair, the RS+/RS

pair, and the

EX+/EX

pair.