A medical device for providing a stimulation therapy includes stimulation circuitry configured to provide a plurality of electrical pulses to be delivered to a patient. The stimulation circuitry contains a microcontroller configured to generate the electrical pulses. Each electrical pulse includes a primary phase, an interphase after the primary phase, and a recovery phase after the primary phase. Consecutive electrical pulses are separated by a standby period. The microcontroller is configured to operate in an active mode during at least one of: the primary phase and the interphase. The microcontroller is configured to operate in a power-conservation mode during a substantial majority of the standby period. The microcontroller consumes substantially less power when operating in the power-conservation mode than in the active mode.