# Looking for Analog to PWM signal -

Hello All:

This may be a repeat post - I looked at my history and did not see it.

I am looking for a product ( finished/qualified) that takes a standard Analog signal ( 0-10V and/or 4-20mA) and converts to a PWM signal with fixed but settable; Frequency of ~ 100 to 5000hZ - possibly with a dip switch.

For example - if using the 0-10V input - at 5V the PWM signal has DS of 50%.

Needs to be hardwired - not a programmable device. In some circles this would be considered a signal conditioner.

DragonPetter
Hi,
You can do this with a 555 timer and a comparator.

You configure the 555 timer to generate a sawtooth waveform, and you feed that waveform into the - input of the comparator, and then your DC voltage setting on the +. As you decrease the voltage level, the ramp voltage will hit it faster each cycle and turn the comparator off for a longer % of the cycle.

I don't know of anything fully qualified since this is a pretty simple circuit that anyone would just make probably.