5

Test Setup

5.1

Test Equipment

5.1.1

Voltage Source:

5.1.2

Multimeters

5.1.3

Output Load

5.1.4

Oscilloscope

5.1.5

Signal Generator

5.1.6

Fan

5.1.7

Recommended Wire Gauge

Test Setup

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WARNING

High voltages, that may cause injury, exist on this evaluation

module (EVM). Please ensure all safety procedures are followed

when working

on

this

EVM.

Never

leave

a

powered

EVM

unattended.

The

use

of

isolated

test

equipment

is

highly

recommended.

See Figure 3 for recommended test set up.

• Source 1: Isolated AC voltage source or VARIAC, capable of 90 VRMS to 264 VRMS at 150 W.

• Source 2: A 3.3-V DC source capable of 100 mA.

Three digital multimeters are recommend, one for current measurement, A1, and two for voltage

measurements, V1 and V2.

It is recommended that actual high brightness LED’s (HB-LED’s) are used for the load. They should be

rated at 0.9 A. The HB-LED’s should be connected in series. Their voltage drop should be between 55

VDC and 110 VDC. Alternatively a constant voltage electronic load could be used. If using a constant

voltage electronic load a 1000-

µF/250 VDC capacitor is required at the input to the electronic load. The

1000

µF capacitor should not be used if using HB-LED’s as the load.

A digital or analog oscilloscope with current probe is required to view the AC current in the PFC inductor

or buck inductor.

A signal generator that can produce a square wave pulse train at between 200 Hz and 1 kHz is required

to do external PWM dimming.

Forced air cooling is not required

A minimum of 18 AWG wire is recommended. Also the wire connections between the AC source and the

EVM, and the EVM and load should be less than two feet long. The AC input connector accepts a

standard IEC320-C13 connector with ground pin.

A 0.9-A Constant Current Supply with PFC for 100-W LED Lighting Applications

6

SLUU355A – March 2009 – Revised June 2009

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