The FAN53330 and FAN5333A/B Evaluation Boards (datasheet) are compact circuits including the FAN5330 SX or FAN5333A/B SX in a 5-Lead SOT23 package and an external Schottky diode which delivers stored inductor current to six of Fairchild's super bright white LEDs. The FAN5330 and FAN5333A/B demo boards are completely assembled and tested surface mount boards, providing easy probe access points to all inputs and outputs so that electrical characteristics and waveforms can be easily measured.

Features

- 1.6MHz PWM Switching Frequency
- Adjustable Output Voltage
- 100mV Feedback Voltage (FAN5330 and FAN333A)
- 300mV Feedback Voltage (FAN5333B)
- Low Shutdown Current: <1uA
- Cycle-by-Cycle Current Limit
- 1.5A Peak Switch Current
- Small 5-lead SOT23 Package

Where To Begin:

1: Connect Vin (1.8 to 5.5V) and Gnd (0V).
2: Use jumper J1 to select "ON" and "OFF" modes.
3: Verify that the output current ILED = .02A for all models.
(Note: ILED = (VREF / R) where VREF = 0.1V(typical) for the FAN5333A/FAN5330 and VREF = 0.3V(typical) for the FAN5333B. R = 5Ohm for the FAN5333A/FAN5330 and R = 15Ohm for the FAN5333B)
4: To verify output current at VOUT, observe that the current remains constant for varying input voltage levels.
5: To verify supply current in “ON” and “OFF” modes, observe that in shutdown mode, supply current will drop below 1uA at Vin.
6: Verify that VOUT is independent of VIN in the 1.8 to 5.5V range and the load current does not exceed its maximum value.
(Note: Although the load current is indirectly limited by the maximum inductor current, VOUT is not allowed to be shorted to ground. Failure results in damaging the Schottky diode and/or the IC)
(Note: The Schottky diode D1, rectifies the voltage pulses generated by the inductor)

Schematic Diagram

PCB Layout

FAN5330/5333A/B List of Materials

To see the schematic at high resolution, go in Download - FAN5330_5333A_B.pdf.
Source: Farichildsemi