AD7740YRTZ-REEL7 (ANALOG DEVICES)

The AD7740YRTZ-REEL7 is an ultrasmall synchronous Voltage-to-Frequency Converter (VFC) works from a single 3.0 to 3.6 or 4.75 to 5.25V supply consuming 0.9mA. The part contains an on-chip 2.5V bandgap reference but the user may overdrive this using an external reference. This external reference range includes VDD. The full-scale output frequency is synchronous with the clock signal on the CLKIN pin. This clock can be generated with the addition of an external crystal (or resonator) or supplied from a CMOS-compatible clock source. The part has a maximum input frequency of 1MHz. For an analog input signal that goes from 0V to VREF, the output frequency goes from 10 to 90% of fCLKIN. In buffered mode, the part provides very high input impedance and accepts a range of 0.1V to VDD - 0.2V on the VIN pin. There is also an unbuffered mode of operation that allows VIN to go from -0.15V to VDD + 0.15V. The modes are interchangeable using the BUF pin.