FTM Board Club
36 to 60VIN, 2.5, 3.3, 5.0, and 12VOUT ZVS Buck Regulator & LED Driver

The PI354x-00 evaluation board demonstrates the features and benefits of the Vicor ZVS high-voltage Buck Regulator family. There are four preconfigured evaluation boards available: PI3542-00-EVAL1 (2.5V), PI3543-00-EVAL1 (3.3V), PI3545-00-EVAL1 (5.0V) and PI3546-00-EVAL1 (12.0V).

The evaluation board provides several options for applying input power (VIN and GND) and output load (VOUT and GND). The user can solder tab style banana jacks or wire, use threaded connectors with retaining nuts, or solder turret pins for clip-on connections.


 The general-purpose amplifier (VDIFF) is preset with a gain of two, but can be easily reconfigured for differential measurements by adding extra 0603 resistors (RD1 – RD5). The lighting option (LGH) can be explored by ordering any of the evaluation boards. When using the lighting option, connections are made between the VIN (anode) and the LGH (cathode) terminals (see Figure 3). Three parallel shunt footprints (2512) are available to program a desired LED constant current. Each evaluation board is preset with a constant current of 1.0A implementing three 0.3Ω resistors in parallel (RS1 – RS3). R6, R7 and C22 are used to set the LGH compensation (please refer to the data sheet for design calculations, theory of operation, as well as maximum compliant voltage requirements). REA1 and REA2 are used to adjust the output voltage regulation. There are additional schematic features that allow a low-frequency dimming circuit (included on the PI3543-00-EVAL1-00 only) to be utilized. This consists of a MOSFET and driver circuit to allow the user to pulse the LED on and off using an external dimming PWM signal. This signal should be limited to less than 10kHz. Since dimming circuity is only available on the PI3543-00-EVAL1, be sure to order that part number if LED dimming is to be explored.