Are there any microcontollers on the market that would be able to drive this relay directly?
If not, what is the most cost effective way to have a microcontroller control 5 relays?
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No uC (microcontroller) operates from 12V (except for 1 pin per uC for very niche application pins in a very few cases).
30 mA is more than the rated current from any uC
Drivers are easy and cheap.
5 x MOSFET. uC drives gate. Source grounded. Drain to rely. Relay to 12V. Reverse diode across relay. eg ZVN2106 [prices(http://search.digikey.com/us/en/products/ZVN2106A/ZVN2106A-ND/92596) and [datasheet]((http://www.diodes.com/datasheets/ZVN2106A.pdf)
Circuit below same for FET or bipolar EXCEPT FET does not need base resistor.
No, none operate at 12V. Use five suitable BJTs.