Methods and apparatuses for a low EMI power supply. The power supply may
include a control circuit, a power switch connected to the control circuit, an
anti-parallel diode connected to the power switch, an inductor coupled to the anti-parallel
diode, an output diode coupled to the inductor, and an output capacitor connected
to the output diode. The power supply may include a series diode and no anti-parallel
diode. The power supply provides a controllable and variable high voltage power
supply from a small number of devices while, at the same time, producing low EMI.
Power conversion is achieved at high efficiencies due to the recycling of energy
in parasitic capacitance. Due to its low EMI, the power supply is particularly
well suited for driving electronic devices such as avalanche photodiodes.
