SPX1580 Datasheet, PDF (1/8 Pages) Sipex Corporation – 7A Ultra Low Dropout Voltage Regulator Fast Response, Adjustable & Fixed

®
SPX1580
7A Ultra Dropout Voltage Regulator
Fast Response, Adjustable & Fixed
FEATURES
■ Low Dropout Voltage 540mV at 7A Full Load Current
■ Adjustable Ouput Down to 1.25V from ATX Power Supply
■ Fixed Output Voltages of 3.3V and 2.5V
■ Extremely Tight Load and Line Regulation
■ Standard 5-Terminal Low Cost TO-220 and TO-263
■ Replacement to Industry Standard LT1580
SPX1580
5 Pin TO-220
123 45
SPX1580
5 Pin TO-263
1 23
APPLICATIONS
■ 3.3V ATX Power Supplies
■ 3.3V to 2.9V for Portable PENTIUM^TM Processor
■ 5V to 3.5V VRE Supply
■ High efficiency "Green" Computer Systems
Now Available in Lead Free Packaging
DESCRIPTION
The SPX1580 is a 7A Low Dropout Regulator with extremely low dropout voltage. The adjustable version
requires only two external resistors to set the output voltage. The fixed version has a preset output of 3.3V
or 2.5V and does not require any external resistors. The SPX1580 features a low dropout of 540mV(Typ.)
and offers fast transient response. This device is suitable for Pentium applications requiring 2.5V from 3.3V
ATX power supplies, where a low current input voltage 1V greater than the output voltage is available. With
an external sense pin the load regulation is less than 1mV. This device is an excellent choice for the use
of powering low voltage microprocessors that require a lower dropout, fast transient response to regulate
from 3.3V and 5V supplies. The SPX1580 is also an excellent choice as a post regulator for switching
supplies applications.
The SPX1580 offers protection against over-current faults, reversed input polarity, over temperature
operation and positive and negative transient voltage.
The SPX1580 is offered in a 5 pin TO-220 and TO-263 compatible with industry standard 5-terminal
regualtors. For 5A, 3A and 1.5A ultra low dropout versions refer to SPX1581, SPX1582 and SPX1583 data
sheets respectively.
TYPICAL APPLICATIONS CIRCUITS
3.3V
V_IN
5V
V_CTRL
V_IN
5
3
C1
SPX1580
33µF
4
1
V_CTRL
2
ADJ
C2
10µF
V_OUT
SENSE
R1
124Ω
R2
124Ω
2.5V
V_OUT
3.3V
V_IN
5V
V_CTRL
C4
68µF
V_IN
5
3 ^VOUT
C1
SPX1580
33µF
4
1
V_CTRL
2
SENSE
C2
10µF
GND
2.5V
V_OUT
C4
68µF
Date: 5/14/04
(1) V_CTRL needed when V_IN < 5V.
(2) V_OUT = V_REF (1+R₂/R₁)+I_ADJ R₂.
(3) V_REF is measured across adjust to sense.
SPX1580 7A Ultra Dropout Voltage Regulator
1
(1) V_CTRL needed when V_IN < 5V.
©Copyright 2004 Sipex Corporation