Pin Description

Pin

Name

Pin

Number

Description

D

1, 15,

16, 17

Drain-

The Drain of the internal N-channel MOSFET, connect to the output load.

S

2, 3, 4, 5

Source-

The source of the internal N-channel MOSFET, connect to the input power source bus

voltage.

SP

6

Positive Sense Input & Clamp:

Connect SP pin to the S pin. The polarity of the voltage

difference between SP and SN provides an indication of current flow direction through the

MOSFET.

FT

7

Fault State Output:

This open collector pin pulls low when a fault occurs. Fault logic inputs

are VC Under-Voltage, Input Under-Voltage, Input Over-Voltage, Forward Over-Current, light

load, reverse current, and Over-Temperature. Leave this pin open if unused.

BK

8

Blanking timer Input-Output:

Connect a resistor from BK to GND to set the blanking time for

the Reverse Comparator function. To configure in slave mode, connect BK to VC. To

configure in master mode with the fastest turn-off response connect BK directly to GND.

SL

9

Slave Input-Output:

This pin is used for paralleling multiple PI2121 solutions in high power

applications. When the PI2121 is configured as the Master, this pin functions as an output

PI2121 is configured in slave mode.

VC

10

Input Supply Pin:

This pin is the supply pin for the control circuitry and gate driver. Connect

a 1μF capacitor between VC pin and the GND pin. Voltage on this pin is limited to 15.5V by

an internal shunt regulator in high auxiliary voltage applications. For high voltage auxiliary

supply applications connect a shunt resistor between VC and the auxiliary supply.

GND

11

Ground:

This pin is ground for the gate driver and control circuitry.

OV

12

Input Over Voltage Input:

The OV pin is used to detect an input source over-voltage

condition in ground referenced applications. When the OV pin voltage crosses the OV

programmable through an external resistor divider. Connect OV to GND to disable this

function.

UV

13

Input Under-Voltage Input:

The UV pin is used to detect an input source under-voltage

condition in ground referenced applications. When the UV pin voltage drops below the UV

programmable through an external resistor divider. Connect UV to VC to disable this function.

SN

14

Negative Sense Input & Clamp-

Connect SN to D pin. The polarity of the voltage difference

between SP and SN provides an indication of current flow direction through the MOSFET.

Package Pin-out

17 Pin LGA (5mm x 7mm)

Top view

Picor Corporation • picorpower.com

PI2121

Rev. 1.0