Description

The PMP30276 is a tampering protected power supply reference design which can withstand an external magnetic field of 200mT. The frequency and amplitude modulation modes and the transformer were optimized for the protection against magnetic tampering at the expense of efficiency. The design uses the UCC28740 flyback controller to generate an isolated output 12V@0.5A (1.0A peak) from an AC input (156VAC-440VAC). The UCC28740 uses an optical coupler to regulate the output and to improve transient response.