7b32-custom Analog Devices, Inc., 7b32-custom Datasheet - Page 2

• Manufacturer Part Number: 7b32-custom
• Description: Isolated Process Current Input
• Manufacturer: Analog Devices, Inc.

GENERAL DESCRIPTION
The 7B32 is a single-channel signal conditioning module that
interfaces, amplifies and filters a process-current input and
provides a protected precision output voltage of either +1V to
+5 V or 0 V to +10 V. Process-current input signals are
measured by reading the voltage across an internal 200Ω
protected resistor. Model 7B32 features a nonlinearity of +0.02%
maximum and an accuracy of +0.1% maximum (+0.01%
typical). To accurately measure low level signals in electrically
noisy environments, 1500 V rms of galvanic transformer-based
isolation with a common mode rejection (CMR) of 105 dB @
50/60 Hz is provided. Rated to operate with a nominal +24
VDC supply, Model 7B32 is mix-and-match and hot-swappable
with other 7B Series input modules, so it can be inserted or
removed from any socket in the same backplane without
disturbing system power.
The floating current input of Model 7B32 is fully protected up
to 120 V rms line voltage. A one-pole 100 Hz filter
preconditions the voltage signal across the 200W protected
input resistor prior to amplification by a low drift amplifier.
Amplitude modulation is used to implement transformer
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Figure 2
isolation(1500 V rms input-to-output and power). Isolated
front-end circuitry power is supplied by a DC/DC converter.
The output section contains a two-pole low pass filter (-3 dB @
100 Hz), a buffer amplifier and a power oscillator. The two-pole
output filter and subsequent buffer ensures that a low noise, low
impedance (<1Ω) signal is available at the output to drive loads
to 2 kΩ minimum
7B32