PWM Q's?

MCUs from Microchip, STMicro, TI, and many others have excellent PWMs built in.

The 16-bit MSP430F5172 from TI is a good one, though limited to 32k flash 2k RAM. It’s only $1.70 in 1,000 qty. The PWM has 4 ns resolution.

From the MSP430F5172 data sheet:

TD0

TD0 is a 16-bit timer/counter with three capture/compare registers supporting up to 256-MHz / 4-ns resolution.

TD0 can support multiple capture/compares, PWM outputs, and interval timing. TD0 also has extensive interrupt capabilities. Interrupts may be generated from the counter on overflow conditions and from each of the capture/compare registers. External fault inputs as well as a external timer counter clear is supported along with interrupt flags from the TEC0 module.

Also STMicro makes a number of stand-alone PWM chips with features like these from the SG2525:

• 8 to 35 v operation
  
• 5.1 v reference trimmed to ± 1 %
  
• 100 hz to 500 khz oscillator range
  
• Separate oscillator sync terminal
  
• Adjustable deadtime control
  
• Internal soft-start
  
• Pulse-by-pulse shutdown
  
• Input undervoltage lockout with hysteresis
  
• Latching pwm to prevent multiple pulses
  
• Dual source/sink output drivers