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14

SC189

Pin Descriptions

Pin #

(MPLD-UT6)

Pin #

(SOT23-5)

Pin Name

Pin Function

1

Not Available

NC

No connection.

2

3

EN

Enable pin. When connected to logic high or tied to VIN pin, the SC189 is on. When con-

nected to logic low, the device enters shutdown and consumes less than 1µA of current.

The enable pin has a 1 MΩ internal pulldown resistor. This resistor is switched in circuit

whenever the EN pin is below the enable input high threshold, or when the part is in un-

dervoltage lockout.

3

1

VIN

Input power supplies. Powers the internal circuitry and is connected to the source of high-

side P channel MOSFET.

4

5

LX

Switching node - connect an inductor between this pin and the output capacitor.

5

2

GND

Ground connection.

6

4

VOUT

Output voltage sense pin.

T

Not Available

Thermal Pad

Thermal pad for heatsinking purposes. This pad is not connected internally. Connect it to

GND plane.