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3

Document No. 6041, Rev. B

W-6237 EVALUATION

The W-6237EVAL2 gives the user a way to evaluate the W-6237 in a typical application of driving multiple LEDs.

The user can connect 6 to 8 LEDs in series to the W-6237 output, using the jumper options for J2, J3 or J4 header-

pin connectors.

The following steps are an example of how the user can evaluate the W-6237 white LED driver:

1) Driving 8 LEDs in series and Shutdown Mode

a)

Connect the 8-LEDs string to the W-6237 output using a jumper shunt on J4 header-pin connector (J2 , J3

not jumpered).

b)

Set the R2 potentiometer to the middle position.

c)

Apply the external voltage supply, Vext (3.0V < VIN < 5V) between VIN (T1) and GND (T2).

d)

The W-6237 is in the shutdown mode (SHDN pin is connected to GND) if the J1 connector is not jumpered.

- Connect a current meter between Vext and VIN pad to measure the shutdown current: ISD << 1 A

- In this mode of operation the LEDs are disconnected from the output: LEDs are OFF

e)

Connect SHDN pin of the W-6237 to VIN using a jumper shunt between Pin #1 and Pin #2 of J1 connector

- Observe that LEDs are ON.

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Table 1. W-6237EVAL2 Board List of Components