WD3124DA

Will Semiconductor Ltd.

2

Oct, 2017 - Rev. 1.2

Pin configuration (Top view)

1

2

3

4

5

6

7

8

9

10 VOUT

PGND

SGND

FB

RSET

VIN

C1

C2

FLASH

EN

GND

Pin descriptions

Symbol

DFN3x3-10L

Descriptions

VIN

1

Input voltage for the charge pump. Decouple with 4.7μF or 10μF ceramic

capacitor close to the pins of the IC.

C1

2

Positive input for the external flying capacitor. Connect a ceramic 1μF

capacitor close to the pins of the IC.

C2

3

Negative input for the external flying capacitor. Connect a ceramic 1μF

capacitor close to the pins of the IC.

FLASH

4

Logic input to toggle operation between FLASH and TORCH mode. In

TORCH mode FB is regulated to the internal 50mV reference. In FLASH

mode FB reference voltage can be adjusted by changing the resistor from

on desired current in TORCH mode and Flash mode.

EN

5

Shutdown control input. Connect to VIN for normal operation, connect to

ground for shutdown. For normal operation, suggest connecting to VIN only

after the VIN has settled if the VIN ramping up is slow.

6

Connect a resistor from this pin to ground. When in FLASH mode (FLASH =

High) this resistor sets the current regulation point according to the following:

FB

7

Feedback input for the current control loop. Connect directly to the current

sense resistor.

SGND

8

Internal ground pin. Control circuitry returns current to this pin.

PGND

9

Power ground pin. Flying capacitor current returns through this pin.

VOUT

10

Charge Pump Output Voltage. Decouple with an external capacitor. At least

1μF is recommended. If Higher value capacitor is used, output ripple is

smaller.