LM1085 Datasheet, PDF (1/8 Pages) National Semiconductor (TI) – 3A Low Dropout Positive Regulators

3A L.D.O. VOLTAGE REGULATOR (Adjustable & Fixed)
LM1085
FEATURES
● Output Current of 3A
● Fast Transient Response
● 0.04% Line Regulation
● 0.2% Load Regulation
● Internal Thermal and Current Limiting
● Adjustable or Fixed Output Voltage(1.5V, 1.8V, 2.5V, 3.3V, 5.0V)
● Surface Mount Package TO-263 3LD & TO-252 3L
● 100% Thermal Limit Burn-in
● Low Dropout Voltage 1.5V at 3A Output Current
● Moisture Sensitivity Level 3
TO-263 PKG
TO-252 PKG
APPLICATIONS
● High Efficiency Linear Regulators / Power Supply
● High Efficiency "Green" Computer Systems
● Constant Current Regulators
● Portable Instrumentation
● SMPS Post-Regulator
● Adjustable Power Supplies
● Powering VGA & Sound Card
1. ADJ / GND 2. OUTPUT 3. INPUT
* Heatsink surface connected to Pin 2.
ORDERING INFORMATION
Device
Package
LM1085R-X.X
TO-263 3LD
LM1085RS-X.X
TO-252 3LD
(X.X=VOUT=1.5V, 1.8V, 2.5V, 3.3V, 5.0V, ADJ)
DESCRIPTION
The LM1085 series of positive adjustable and fixed regulators are designed to provide 3A with high efficient.
All internal circuitry is designed to operate down to 1.5V input to output differential.
On-chip trimming adjusts the reference voltage to 1%.
It's low dropout voltage and fast transient response make it ideal for low voltage microprocessor applications.
Internal current and thermal limiting provides protection against any overload condition that would create
excessive junction temperature.
TEST & TYPICAL APPLICATION CIRCUIT
LM1085-3.3V
LM1085-ADJ
Note
(1) C1 needed if device is far away from filter capacitors.
(2) C2 minimum value required for stability
V_REF=V_OUT-V_ADJ=1.25V(Typ.)
I_ADJ=55㎂(Typ.)
V_OUT = V_REF x (1+RF2/RF1) + I_ADJ x RF2
Nov. 2010-Rev. 1.4
-1-
HTC