AP8802EV2

Issue 5 August 2009

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© Diodes Incorporated 2009

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Figure 3: Component layout and circuit board view

AP8802EV2 Connection Point Definition

Name

Description

VIN

Positive supply voltage.

GND

Supply Ground (0V).

CTRL

Internal voltage ref. pin (1.25V). This pin can be used to achieve dimming and

soft-start, and for switching the output current off.

•

Leave floating for normal operation.

•

See 'Circuit Features' section to achieve dimming, soft-start and for

switching the output current off.

LED A

LED A

connects to the external LED anode

LED K

LED K

connects to the external LED cathode

AP8802EV2 BASIC OPERATION AT FULL VOLTAGE

1.

Connect external LEDs across the test pins ‘LED A’ (anode) and ‘LED K’ (cathode). The

number of external LEDs that can be connected depends on their operating power and

forward voltage drop, but typically 12 x 3.2V LEDs can be connected using a 45V rail. For an

external load other than LEDs, the positive terminal of the load should be connected to the

anode and the negative to the cathode.

2.

Connect VIN and GND.

Warning: The board does not have reverse battery/supply protection.

3.

Set the PSU to the desired input voltage (usually between 12V and 45V)

4.

Turn on the PSU. The external LEDs will illuminate and the current should be

approximately 1A

5.

The switching waveform on the SW pin can be acquired using the test point J1

Warning: Do not stare at the LEDs directly.

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