• Industrial and Telecom Applications
• Isolated Flyback Converters
• PLC I/O Modules
• Wide-Range DC-Input Isolated Power Supplies

The MAX17690E evaluation kit (EV kit) is a fully assembled and tested circuit board that demonstrates the operation of an isolated 16.5W no-opto flyback DC-DC converter with secondary-side synchronous rectification. This circuit is implemented using the MAX17690, a no-opto, flyback controller in a 16-pin TQFN package with an exposed pad. The synchronous rectification on the secondary side is enabled by replacing the secondary diode with a MOSFET to achieve 84.7% efficiency. The circuit uses the MAX17606, a secondary-side synchronous rectifier driver in a 6-pin SOT23 package for driving the secondary-side MOSFET.

The EV kit output is con gured for an isolated +3.3V and provides up to 5A of output current. The EV kit is programmed to operate at a 200kHz switching frequency. The transformer provides the galvanic isolation between input and output, up to 1500V_RMS. The EV kit regulates the output voltage within ±5% over the line, load, and temperature without using the auxiliary winding/optocoupler for output voltage feedback.