RDR-866 - 2.5 W non-isolated power supply, using LinkSwitch-TNZ to generate AC zero-crossing signals losslessly

This engineering report describes a non-isolated buck converter power supply with an input line zero-crossing detection (ZCD) output signal. Nominal output is 5 V, 500mA over 90-300 VAC input range. The PSU is powered by the LinkSwitch-TNZ IC controller. The LinkSwitch-TNZ family of ICs combines power conversion with lossless generation of AC zero-crossing signals, typically used in system clocking and timing functions. The device integrates a 725 V power MOSFET, oscillator, high-voltage switching current source for self-biasing, frequency dithering, fast (cycle-by-cycle) current limit, hysteretic thermal shutdown, and output and input overvoltage protection circuitry on a monolithic IC . Designs using the highly integrated LinkSwitch-TNZ IC are more flexible than discrete implementations, reducing component count by 40% or more. Key design goals are low cost, low audible noise and compact form factor suitable for wireless (WiFi, NBIoT, etc.) and relay power. This file contains power supply specifications, schematics, bill of materials, transformer documentation, printed circuit layout, performance and test data.