The AP7510 utilizes an unique combination of digital and analog conversion techniques, which features adjustable scaling and approaches the nearly absolute accuracy of purely digital fre- quency division. The Frequency Scaler accepts a variety of signal inputs, such as sine wave, square wave and pulses. It can also accept a contact closure input by attaching a jumper across pins 4 and 6. A top-mounted, single-turn sensitivity potentiometer permits an adjustable input sensitivity from 50mV to 5V. The conditioned and amplified frequency input is fed into an optocoupler, which consists of an LED and a phototransistor encapsulated in the same housing.
The optocoupler provides full DC to DC isolation and feeds the input into the digital frequency divider circuitry. The input is then divided down and channelled through an over-current-protected output driver. The result is a proportionally reduced square wave frequency output. If a 5V TTL-compatible output is desired, use pins 9 and 10 for output. If a 24V square wave output is desired, connect the load between pins 7 and 9.
The AP7510 Frequency Scaler can be used to directly interface between totalizers and turbine flowmeters, magnetic tachometer sensors and other frequency transducers. A continuously adjustable scaling factor (input-to-output ratio) of 0.00001 to 0.99999 is provided to precisely match the frequency transducer and totalizer. The AP7510 provides a square wave output which can be used to drive electronic counters with TTL, CMOS, or 24V inputs.