Techniques are provided herein for generating PWM signals. Furthermore, a direct-drive method is disclosed in which a PWM signal is generated as a differential signal made up of OUTP and OUTN signals, where OUTP is a copy of OUTN but shifted in time by half a period. The PWM signal is generated by passing each of an input period and an input duty cycle through corresponding sigma-delta circuits to generate a refined period and a refined duty cycle, respectively. In some example cases, a threshold mapper uses a lookup table (LUT) or similar mechanism to select timing thresholds for rise times and fall times for each of the OUTP and OUTN signals, where the timing thresholds are selected based on the refined period and the refined duty cycle. In some example cases, a pulse generator generates the OUTP and OUTN signals based on the timing thresholds.