Re: 300 mA from a microcontroller pin

Tomás Ó hÉilidhe wrote:

I have a 14-pin PIC microcontroller, the 16F684 to be exact. Each pin can be either 5 V, 0 V or high impedance, however they can only source or sink 25 mA, but I need 300 mA (both sourced and sunk). Currently, I'm using a setup consisting of an NPN and a PNP transistor in order to provide more current, like so: http://img124.imageshack.us/img124/6215/
driverbeforegj7.jpg (the microcontroller is on the far left).

I've heard of things called "drivers" that can be used to boost the current, whilst still being able to provide the three states of 5 V, 0 V and high impedance. I've searched the web and come across things like the ULN2003 the MAX15025, but I'm having difficulty finding what I want. It seems that the ones that can provide enough current can only source current, while the ones that can source and sink tend not to be able to provide enough current.

Can someone please suggest a driver chip so that I can effectively get 300 mA out of my microcontroller pins? Remember that I need the three states.


What are you driving that you need 3-state 300 mA outputs ? Depending on the application, there may be alternative solutions.
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