LTC1772HS6 View Datasheet(PDF) - Linear Technology

Part Name

Description

Manufacturer

LTC1772HS6

Constant Frequency Current Mode Step-Down DC/DC Controller in SOT-23

Linear Technology 

LTC1772

PIN FUNCTIONS

ITH/RUN (Pin 1): This pin performs two functions. It

serves as the error amplifier compensation point as well as

the run control input. The current comparator threshold

increases with this control voltage. Nominal voltage range

for this pin is 0.7V to 1.9V. Forcing this pin below 0.35V

causes the device to be shut down. In shutdown all

functions are disabled and the PGATE pin is held high.

GND (Pin 2): Ground Pin.

VFB (Pin 3): Receives the feedback voltage from an exter-

nal resistive divider across the output.

SENSE– (Pin 4): The Negative Input to the Current Com-

parator.

VIN (Pin 5): Supply Pin. Must be closely decoupled to GND

Pin 2.

PGATE (Pin 6): Gate Drive for the External P-Channel

MOSFET. This pin swings from 0V to VIN.

W

FUNCTIONAL DIAGRA

VIN SENSE–

5

4

+

ICMP

–

SLOPE

OSC

COMP

RS1

R

Q

S

SWITCHING

LOGIC AND

BLANKING

CIRCUIT

VIN

PGATE

6

VIN

0.3V

GND

2

FREQ

FOLDBACK

SHORT-CIRCUIT

DETECT

0.3V

0.15V

BURST

+

CMP

–

SLEEP

0.5µA

VIN

VOLTAGE

REFERENCE

UNDERVOLTAGE

LOCKOUT

1 ITH/RUN

0.35V

VREF

0.8V

+

SHDN

CMP

–

SHDN

UV

OVP

EAMP

VREF

+

60mV

VREF

0.8V

VFB

3

VIN

1.2V

1772 FD

1772fb

4

Share Link: