Tunable triangular pulse-generator for ISM band radar

A simple tunable triangular pulse-generator for 24 GHz ISM band pulse radar is reported, which consists of V–I converters and charge pumps where the control signals are produced by a resistive ladder, digital logic, and switches. In the proposed pulse-generator, by applying tunable input signals to the V–I converters, the amount of currents flowing through the charge pumps can be controlled without requiring the current source switching, and thus the switching noise can be avoided. Implemented in a 0.13 μm CMOS technology, measured tuning ranges of pulse-width and -amplitude are 12.7–28.5 ns and 15.0–216.1 mVpp, respectively, while dissipating 4.5 mW from a 1.5 V supply.