MSP1250

Power Converter 150kHz 3A

Step-down Voltage Regulator

Connection Diagrams and Ordering Information

Bent and Staggered Leads, Through Hole

Package

Surface Mount Package

5-Lead TO-220 (T)

5-Lead TO-263 (S)

PIN FUNCTIONS

+VIN —This is the positive input supply for the IC switching regulator. A suitable input

bypass capacitor must be present at this pin to minimize voltage transients and to supply

the switching currents needed by the regulator.

Ground —Circuit ground.

Output —Internal switch. The voltage at this pin switches between (+VIN - VSAT) and

approximately -0.5V, with a duty cycle of approximately VOUT/VIN. To minimize coupling to

sensitive circuitry, the PC board copper area connected to this pin should be kept to a

minimum.

FeedBack —Senses the regulated output voltage to complete the feedback loop.

—Allows the switching regulator circuit to be shut down using logic level signals

thus dropping the total input supply current to approximately 80 µA. Pulling this pin below

a threshold voltage of approximately 1.3V turns the regulator on, and pulling this pin above

1.3V

(up to a maximum of 25V)

shuts the regulator down. If this shutdown feature is not

needed, the

pin can be wired to the ground pin or it can be left open, in either