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Document No. 6041, Rev. B

Figure 2. W-6237EVAL2 Board

The board is powered from an external voltage applied to the VIN (T1) pad. The circuit is delivered with the jumper

shunt on the J4 connector, which connects the 8 LEDs string available on board to the W-6237 output. The user

can move the jumper to other connector, J2 or J3, if he desires to connect a different number of LEDs (6 or 7 LEDs).

The user can connect his own white LEDs between VOUT (T7) and LED (T10) test points, with no jumper shunt set

to any of J2 to J4 connectors.

The LED current is set through the external resistors connected to the FB pin (R1, R2). Using the variable resistor R2,

the LED current can be set from 3mA to 30mA. Most white LEDs are driven at a maximum current between 15mA and

20mA to ensure a pure "white" light.

The board also demonstrates the W-6237 shutdown mode and LED brightness control by using an external PWM

signal or DC voltage. Resistor R3 and R5 (R5 – soldered on board by the user) are used to adjust the LED current

using the dimming control with an external applied DC voltage on the FB pin. The ON/OFF operation and dimming

control can be selected using the jumper options for the J1 connector.

Test points T1 to T10 are available to apply the external voltages/signal generator or to measure the output voltages

/ signals provided by W-6237.

The component placement is shown in Figure 2. Table 1 presents the component list for this evaluation board.

W-6237

W-6237EVAL2 Rev.1.0

W-6237

COPAL ELECTRONICS

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