Dual mode Digital Pulse Modulation (PWM & PFM) generator ASIC for Laser Electro-Optic Q-switching application

Due to the wide applications of DPWM (Digital Pulse Width Modulation) /DPFM (Digital Pulse Frequency Modulation) in the industry, a 4-bit Dual Mode (PWM/PFM) Digital Pulse Modulation (DMDPM) 40-pin 0.5 μm-process CMOS chip is designed, fabricated, and tested. The chip has an optimized occupation area (of the un-scaled chip) of (1105λ × 1080λ = 331.5μm × 324μm) ~ 13.26% of the allowed area (3000λ × 3000λ), and a maximum frequency of 150 MHz. Beside simulation results, experimental chip test results are presented as well. An application of proposed scheme is applied in Laser Electro-Optic Q-switching. The advantage of wide range of pulse durations/frequencies offered by our chip, is utilized to electro-optically modulate a Laser light. Our dual mode DMDPM chip would further allow to modulate various Lasers meeting their pump pulse duration requirement.