Design and analysis of a frequency division and duty cycle control circuit for

In this article, a complementary metal-oxide-semiconductor (CMOS) frequency and duty cycle controller (FDCC) is presented for on-chip signal synthesis. The circuit consists of a few logic gates and a voltage-controlled oscillator, and is functionally similar to a programmable divide-by-N frequency divider. It is designed for driving integrated sensor and actuator systems. Compared with other frequency dividers with the same control flexibility, the proposed circuit features a compact topology and allows the control over the output signal duty cycle. For the proof-of-concept, a prototype 1 x 4 array of identical FDCCs has been fabricated on a 0.35 mu m Austria Mikro Systeme (AMS) CMOS process. Each FDCC occupies an active area of 0.0051 mm2, which is area-efficient. The array has been validated to generate 4 synchronized 4 MHz similar to 64 MHz outputs with a duty cycle tuning range of 3.125% similar to 96.875%. Although driven by a 5-V power supply, it still provides a relatively high power-efficiency of 1.26 GHz/mW.