LD6919

4/12/2010

1

Leadtrend Technology Corporation

www.leadtrend.com.tw

LD6919-DS-00b April 2010

500mA, Ultra-Low Noise, High PSRR CMOS LDO Regulator

with Soft Start Function

REV: 00b

General Description

The LD6919 is a micro power linear regulator with very low

output voltage drop during load transient, featuring

ultra-low noise, low-dropout and high ripple rejection ratio

for optimal performance of battery-powered systems. This

SS pin can suppress the noise and is built in with soft start

function. Using Leadtrend’s own proprietary control

scheme, the output voltage can be set by the value chosen

stable with an output capacitor of 1

μF which reduces the

board space and cost.

The LD6919 is available in a space saving SOT25,

SC70-6 and WDFN-6L 1.6mm x 1.6mm package.

+Patented

Features

Wide Operating Input Voltage Range：2.5V to 5.5V

Very-Low Output

Voltage

Drop

during

Load

Transient

Ultra-Low Noise for RF Application

Shutdown Current <1

μA

High PSRR 70dB@1kHz

Stable with 1

μF Output Capacitor

Thermal Shutdown and Current Limiting Protection

Soft Start Operation

Fixed Output Voltage: 1.5V to 3.3V (step：0.1V) and

Applications

Battery-Powered Equipment

Hand-Held Instruments

Palmtops, Notebook Computers

Typical Application

Fig. 1 Typical Application Circuit for General Purpose

Reference example

3.1V

2.2M

3.0V

680k

2.8V

510k

2.7V

300k

2.5V

100k

1.8V

)

R

(w/o

V

73

)

k

(

R

)

k

(

R

)

(w.R

V

J

OUT

J

J

J

OUT

×

+

Ω

Ω

=