GENERAL DESCRIPTION

The AD7750 is a Product-to-Frequency Converter (PFC) that can be configured for power measurement or voltage-to-frequency conversion. The part contains the equivalent of two channels of A/D conversion, a multiplier, a digital-to-frequency converter, a reference and other conditioning circuitry. Channel 1 has a differential gain amplifier with selectable gains of 1 or 16. Channel 2 has a differential gain amplifier with a gain of 2. A high pass filter can be switched into the signal path of Channel 1 to remove any offsets.

FEATURES

Two Differential Analog Input Channels

Product of Two Channels

Voltage-to-Frequency Conversion on a Single Channel

Real Power Measurement Capability

< 0.2% Error Over the Range 400% Ibasic to 2% Ibasic

Two or Four Quadrant Operation (Positive and Negative Power)

Gain Select of 1 or 16 on the Current Channel (Channel 1)

Choice of On-Chip or External Reference

Choice of Output Pulse Frequencies Available (Pins F1 and F2)

High Frequency Pulse Output for Calibration Purposes (FOUT)

HPF on Current Channel for Offset Removal

Single 5 V Supply and Low Power