recommend voltage doubler ic ?

None of the voltage doubler IC's that I've seen will provide that much current - they're intended for just a couple of milliamps. You'll most likely need to make a switch-mode DC-DC converter, or find a module (although 12v to 24v doesn't seem to be very common).

Peter

Don't know if it helps but Powerbox make a 12v-24v dc-dc converter module that will do 100mA. They are in the Farnell catalogue but can be had cheaper direct from Powerbox (might be a MOQ though, I've only ever ordered qty from them). Available as a PCB mounted module or in a chassis with screw terminals.

James

I'm with Pete - AFAIK all the doubler IC's are small current. Options are a small switcher like an MC34063, or a dedicated Kemo module if the 24V doesn't require tight regulation.

I'll say the same as the other respondents. Unless you're building thousands, just use an off-the-shelf converter module. The 'capacitor doubler' type chips are only meant for 10mA ? at most.

Graham

-- due to the hugely increased level of spam please make the obvious adjustment to my email address

Actually there are quite a few switched capacitor inverters/doublers that will do over 100mA (e.g. MAX660, MAX1680), but the problem is the 24V operation.

I agree, a DC-DC converter module is the best way to go, something like this:

Dave.