Complex in-bore electronics (e.g. motion trackers, digitizer etc.) frequently requires various voltage rails. This poses especially a challenge when bi-polar voltages are required because in-bore voltage inversion is typically not possible due to the EMI of such converter. The here presented switched capacitator voltage inverter allows in-bore operation without disturbing the MRI scanner due to the very low EMI. Lab and 3T MRI measurement were performed to verify the EMC compatibility and characterize the device.