CYStech Electronics Corp.
3A Low Dropout Positive Voltage Regulator
Spec. No. : C540F3
Issued Date : 2003.06.25
Revised Date :
Page No. : 1/4
PL1085-XXXF3
Features
Dropout Voltage 1.3V at 3A Output Current.
Fast Transient Response.
Extremely Tight Line and Load Regulation.
Current Limiting and Thermal Protection.
Adjustable Output Voltage or Fixed 1.5V, 1.8V, 2.5V, 2.85, 3.0V, 3.3V, 3.5V, 5.0V.
Standard 3-Pin Power Packa
ges.
TO-263
Description
The PL1085-XXXF3 is a low dropout three terminal regulator with 3A output current capability. The output voltage is
adjustable with the use of a resistor divider or fixed 1.5V, 1.8V, 2.5V, 2.85V, 3.0V, 3.3V, 3.5V and 5.0V. Dropout voltage is
guaranteed to be at maximum of 1.3V with the maximum output current. Its low dropout voltage and fast transient response
make it ideal for low voltage microprocessor applications. Current limit and thermal protection provide protection against
any overload condition that would create excessive junction temperatures.
Applications
Mother Board I/O Power Supplies.
Microprocessor Power Supplies.
High Current Regulator.
Post Regulator for Switching Supply.
Typical Application Circuit
Vin=5V
Vout=3.3V
ADJ
C1
10μF
VREF
R1
125Ω
1%
R2
205Ω
1%
C2
10μF
V
REF
=V
OUT
-V
ADJ
=1.25V(typ)
V
OUT
=V
REF
(1+R
1
/R
2
)+I
ADJ
×R
2
I
ADJ
=55µA(typ.)
(1)C1 needed if device is far
away from filter capacitors.
(2)C2 required for stability.
Adjustable Voltage Regulator
Vin=5V
Vout=3.3V
C1
10μF
GND
C2
10μF
Fixed Voltage Regulator
PL1085F3
CYStek Product Specification