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FEATURES
Low Cost
Single or Dual Supply, 5 V to 36 V, ⴞ5 V to ⴞ18 V
Full-Scale Frequency Up to 500 kHz
Minimum Number of External Components Needed
Versatile Input Amplifier
Positive or Negative Voltage Modes
Negative Current Mode
High Input Impedance, Low Drift
Low Power: 2.0 mA Quiescent Current
Low Offset: 1 mV PRODUCT DESCRIPTION The AD654 is a monolithic V/F converter consisting of an input
amplifier, a precision oscillator system, and a high current output
stage. A single RC network is all that is required to set up any
full scale (FS) frequency up to 500 kHz and any FS input voltage
up to ± 30 V. Linearity error is only 0.03% for a 250 kHz FS,
and operation is guaranteed over an 80 dB dynamic range. The
overall temperature coefficient (excluding the effects of external
components) is typically ± 50 ppm/°C. The AD654 operates from
a single supply of 5 V to 36 V and consumes only 2.0 mA quiescent current.
The low drift (4 µV/°C typ) input amplifier allows operation
directly from small signals such as thermocouples or strain gauges
while offering a high (250 MΩ) input resistance. Unlike most …