A 1-5 GHz Frequency-to-Voltage Converter Using Limiting Amplifier

Abstract

A frequency-to-voltage converter (FVC) is designed for directly converting an input radio-frequency to a dc output voltage over a wide microwave frequency range. The proposed circuit consists of a limiting amplifier (LA) for converting input frequency to correspond ac magnitude and a power detector for ac magnitude to dc voltage conversion. Consequently, the circuit converts the signal frequency of 1-5 GHz to the measured dc voltage of 0.25-1.39 V under the input power level at +5 dBm. The RMS error is below 1.37 %. Implemented in 0.18 mu m CMOS technology, the dc power consumption varies from 17.4 to 19.4 mW with 1.8 V supply voltage, depending on the input frequency. The fabricated chip occupies the size of 860 x 500 mu m(2).