A
M I C R O S E M I
LX8384x-xx
5A Low Dropout Positive Regulators
C O M P A N Y
P RODUCTION
The LX8384/84A/84B Series ICs are
positive regulators designed to provide 5A
output current. These regulators yield
higher efficiency than currently available
devices with all internal circuitry designed
to operate down to a 1V input-to-output
differential. In each of these products, the
dropout voltage is fully specified as a
function of load current. Dropout is
guaranteed at a maximum of 1.3V (8384A)
and 1.5V (8384) at maximum output
current, decreasing at lower load currents.
In addition, on-chip trimming adjusts the
reference voltage tolerance to 1% maximum
at room temperature and 2% maximum over
the 0 to 125°C range for the LX8384A,
making this ideal for the Pentium P54CVRE specification. The LX8384B offers
0.8% tolerance at room temperature and
1.0% maximum over line, load and
temperature.
Fixed versions are also
available and specified in the Available
Options table below.
The LX8384/84A/84B Series devices are
pin-compatible with earlier 3-terminal
regulators, such as the 117 series products,
but they do require input and output
capacitors. A minimum 10µF capacitor is
required on the input and a 15µF or greater
on the output of these new devices for
stability. Although, these capacitors are
generally included in most regulator
designs.
The LX8384/84A/84B Series quiescent
current flows into the load, thereby
increasing efficiency. This feature contrasts
with PNP regulators where up to 10% of the
output current is wasted as quiescent
current. The LX8384-xxI is specified over
the industrial temperature range of -25°C to
125°C, while the LX8384-xxC/84AxxC/84B-xxC is specified over the
commercial range of 0°C to 125°C.
IMPORTANT: For the most current data, consult MICROSEMI’s website: http://www.microsemi.com
Three-Terminal Adjustable Or
Fixed Output
Guaranteed < 1.3V Headroom a
5A (LX8384A)
Guaranteed 2.0% Max.
Reference Tolerance (LX8384A)
Guaranteed 1.0% Max.
Reference Tolerance (LX8384B)
0.015% Line Regulation
0.15% Load Regulation
W W W . Microsemi . COM
®
Pentium Processor VRE
Application
High Efficiency Linear
Regulators
Power Regulators For Switching
Power Supplies
Battery Chargers
Constant Current Regulators
®
Cyrix 6x86™
AMD-K5™
IN
OUT
3.5V
at 5A
LX 8384A
5V
+
*1500µ F
6M V1500G X
S an yo
121 Ω
0.1%
AD J
+
1500µ F
5x 6M V1500G X
Sanyo
218 Ω
0.1%
LX8384/84A/84B-00
Adjustable
LX8384/84A/84B-15
1.5V
LX8384/84A/84B-33
3.3V
Table 1 - Available Options
* C apacitors must have < 20m Ω
T otal E S R for the V R E Specification
An Application of the LX8384A for the Pentium P54C Processors Meeting VRE Specification.
LX8384X
Max Ref Max Dropout
Accuracy
Voltage
0 to 125
2.0%
1.5V
2.0%
1.3V
1.0%
1.3V
-25 to 125 2.0%
1.5V
TA (°C)
Plastic TO-252
(D-Pak) 3-Pin
LX8384-xxCDT
LX8384A-xxCDT
LX8384B-xxCDT
LX8384-xxIDT
DT
Plastic TO-220
3-Pin
LX8384-xxCP
LX8384A-xxCP
LX8384B-xxCP
LX8384-xxIP
P
Plastic TO-263
3-Pin
LX8384-xxCDD
LX8384A-xxCDD
LX8384B-xxCDD
LX8384-xxIDD
DD
Note: Available in Tape & Reel.
Append the letter “T” to the part number. (i.e. LX8384-xxCPT)
Copyright 2000
Rev. 2.1d, 2001-03-15
Microsemi
Linfinity Microelectronics Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 1
A
M I C R O S E M I
LX8384x-xx
5A Low Dropout Positive Regulators
C O M P A N Y
P RODUCTION
Power Dissipation....................................................................................Internally Limited
Input Voltage .................................................................................................................10V
Input to Output Voltage Differential..............................................................................10V
Operating Junction Temperature
Plastic (DT, DD, P Packages)................................................................................ 150°C
Storage Temperature Range .......................................................................-65°C to 150 °C
Lead Temperature (Soldering, 10 Seconds)............................................................... 300°C
W W W . Microsemi . COM
TA B is V O U T
3
V IN
2
V OUT
1
AD J /
GND*
DD PACKAGE (3-PIN)
(Top View)
Note 1: Exceeding these ratings could cause damage to the device. All voltages are with respect to
Ground. Currents are positive into, negative out of specified terminal.
TA B is V O UT
V IN
3
2
DD
Plastic TO-263 3-Pin
THERMAL RESISTANCE-JUNCTION TO AMBIENT, θJA
THERMAL RESISTANCE-JUNCTION TO TAB, θJT
AD J/
G ND *
1
60°C/W
2.7°C/W
DT PACKAGE (3-PIN)
(Top View)
TA B is V O U T
P
Plastic TO-220 3-Pin
THERMAL RESISTANCE-JUNCTION TO AMBIENT, θJA
THERMAL RESISTANCE-JUNCTION TO TAB, θJT
V O UT
60°C/W
2.7°C/W
3
V IN
2
V OUT
AD J /
G N D*
1
DT
Plastic TO-252 3-Pin
THERMAL RESISTANCE-JUNCTION TO AMBIENT, θJA
THERMAL RESISTANCE-JUNCTION TO TAB, θJT
P PACKAGE (3-PIN)
60°C/W
2.7°C/W
(Top View)
*Pin 1 is GND for fixed voltage versions
Junction Temperature Calculation: TJ = TA + (PD x θJT).
The θJA & θJT numbers are guidelines for the thermal performance of the device/pc-board
system. All of the above assume no ambient airflow.
V IN
B ias C ircuit
Bandgap
C ircuit
C ontrol
C ircuit
O utput
C ircuit
PACKAGE DATA
Therm al
Lim it C ircuit
V O UT
SO A
Protection
C ircuit
A D J or
GND*
C urrent
Lim it C ircuit
*Pin 1 is GND for fixed voltage versions
Copyright 2000
Rev. 2.1d, 2001-03-15
Microsemi
Linfinity Microelectronics Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 2
A
M I C R O S E M I
LX8384x-xx
5A Low Dropout Positive Regulators
C O M P A N Y
P RODUCTION
Unless otherwise specified, the following specifications apply over the operating ambient temperature for the LX8384x-xxC with
0°C ≤ TA ≤ 125°C and the LX8384-xxI with -25°C ≤ TA ≤ 125°C except where otherwise noted. Test conditions: VIN -VOUT = 3V;
IOUT = 5A. Low duty cycle pulse testing techniques are used which maintains junction and case temperatures equal to the ambient
temperature.
Parameter
Symbol
Min
LX8384x-xx
Typ
Max
Units
LX8384-00 / 8384A-00 / 8384B-00 (ADJUSTABLE)
Reference Voltage
(Note 4)
LX8384/84A-00
VREF
LX8384B-00
Line Regulation (Note 2)
REF
Load Regulation (Note 2)
REF
Thermal Regulation
OUT
(VIN)
(IOUT)
(Pwr)
Adjust Pin Current
LX8384-00
LX8384A/84B-00
ADJ
Minimum Load Current
IOUT(MIN)
Maximum Output Current
IOUT(MAX)
Long Term Stability (Note 3)
OUT(t)
OUT(T)
1.238
1.250
1.262
V
1.225
1.250
1.270
V
1.240
1.250
1.260
V
1.238
1.250
1.262
V
0.015
0.2
%
1.3V < (VIN -VOUT), VIN < 10V, IOUT = 10mA
VOUT > VREF, VIN - VOUT = 3V,
10mA < IOUT < 5A
0.035
0.3
%
0.15
0.5
%
TA = 25°C, 20ms pulse
0.01
0.02
%/W
IADJ
Adjust Pin Current Change (Note 4)
Dropout Voltage
IOUT = 10mA, TA = 25°C
10mA < IOUT < 5A, 1.5V < (VIN -VOUT),
VIN < 10V, P < PMAX
IOUT = 10mA, TA = 25°C
10mA < IOUT < 5A, 1.5V < (VIN -VOUT),
VIN < 10V, P < PMAX
1.3V < (VIN -VOUT), VIN < 7V, IOUT = 10mA
VOUT = 5V, f= 120Hz, COUT = 100µF Tantalum,
VIN = 6.5V, CADJ = 10µF, IOUT = 5A
Ripple Rejection (Note 3)
Test Conditions
65
20
10mA < IOUT < IOUT(MAX), 1.3V < (VIN -VOUT), VIN