Microsemi
Integrated Products Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 1
Copyright © 2001
Rev. 1.4b, 2005-05-04
WWW.Microsemi .COM
LX8580A
7.5A Ver
y
Low Dropout Positive Re
g
ulator
P
RODUCTION
D
ATA
S
HEET
TM ®
DESCRIPTION
The LX8580A is a high-
performance, very low dropout voltag e
regulator, designed for use with
advanced microprocessors, micro
controllers, or video graphics
controllers. This product can be used
with separate voltage supplies for the
control and power sections, allowing a
power regulation dropout voltage as
low as 100mV @ 1.5A. In AGP bus
systems requiring regulation of 3.3V
to 2.85V @ 3A, the LX8580A has a
max dropout of 250mV making it an
ideal power supply solution for today’s
graphics applications.
The LX8580A can also be used in a
single voltage supply configuration
with a dropout performance
similar to that of the LX8584 (1.3V @
7.5A).
The LX8580A is supplied in a five-
terminal TO-220, TO-263, or Linfinity’s
S-PAK packages, which allows the
implementation of remote (Kelvin)
voltage sensing. This sensing
compensates for output voltage
variations due to load changes and
resistive voltage drops in connectors and
board traces. Typical load regulation
measured at the sense pin is less that
1mV for a load current step of 7mA to
7.5A.
The LX8580A is ideal fo r generatin g a
secondary 2V-2.85V low voltage supply
on a motherboard where a 3.3V supply
is already available.
IMPORTANT: For the most current data, consult MICROSEMI’s website: http://www.microsemi.com
KEY FEATURES
Low Dropout, 650mV at 7.5A
Output Current in Dual Supply
Mode
Fast Transient Response
Remote Sensing
1mV Load Regulation
Adjustable Output
APPLICATIONS/BENEFITS
Microprocessor/Micro controller
Supplies
3.3V to 2.85V Voltage
Conversion
High-Current Regulators
Post Regulation for Switching
Power Supplies
PRODUCT HIGHLIGHT
V
CTRL
≥
V
OUT
+ 1.3V Max V
OUT
V
PW R
≥
V
OUT
+ V
DROPOUT
LX8580A
V
PWR
V
CTRL
4
1
3
2
5ADJUST
SENSE
OUTPUT
R
1
R
2
R
L
2
1
2
1
RI
R
R
VV ADJREFOUT
×+
⎟
⎟
⎠
⎞
⎜
⎜
⎝
⎛
+=
PACKAGE ORDER INFO
P
Plastic TO-220
5-Pin
DF
S-PAK
5-pin
DD
Plastic TO-263
5-PIN
T
A
(°C) D
ROPOUT
V
OLTAGE
RoHS Compliant
Transition DC: 0515
0 to 125 0.1V – 0.7V LX8580A-00CP LX8580A-00CDF LX8580A-00CDD
Note: Available in Tape & Reel. Append the letters “TR” to the part number. (i.e. LX8580A-00CDD-TR)
L
LX
X8
85
58
80
0A
A
Microsemi
Integrated Products Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 2
Copyright © 2001
Rev. 1.4b, 2005-05-04
WWW.Microsemi .COM
LX8580A
7.5A Ver
y
Low Dropout Positive Re
g
ulator
P
RODUCTION
D
ATA
S
HEET
TM ®
ABSOLUTE MAXIMUM RATINGS
V
CTRL
Input Voltage.........................................................................................13V
V
PWR
Input Voltage............................................................................................7V
Power Dissipation......................................................................Internally Limited
Operating Junction Temperature.................................................................. 150°C
Storage Temperature Range...........................................................-65°C to 150°C
Lead Temperature (Soldering 180 seconds) ................................................ 300°C
RoHS Peak Package Solder Reflow Temperature (40 second maximum exposure) .......260°C (+0, -5)
Note: 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
.
PACKAGE PIN OUT
P P
ACKAGE
(5-P
IN
)
(Top View)
1
2
3
TAB is OUTPUT
4
5
OUTPUT
V
PWR
V
CTRL
ADJUST
SENSE
DD PACKAGE (5-PIN)
(Top View)
1
SENSE
OUTPUT
V
PWR
2
3
TAB is OUTPUT
4
5
V
CTRL
ADJUST
DF P
ACKAGE
(Top View)
TAB is OUTPUT
1
SENSE
ADJUST
OUTPUT
V
CTRL
V
PWR
2
3
4
5
RoHS 100% Matte Tin Lead Finish
THERMAL DATA
P
Plastic TO-220 5-Pin
THERMAL RESISTANCE
-
JUNCTION TO
T
AB
,
θ
JT
3.0°C/W
THERMAL RESISTANCE
-
JUNCTION TO
A
MBIENT
,
θ
JA
65°C/W
DD
Plastic TO-263 5-Pin
THERMAL RESISTANCE
-
JUNCTION TO
T
AB
,
θ
JT
3.0°C/W
THERMAL RESISTANCE
-
JUNCTION TO
A
MBIENT
,
θ
JA
35°C/W
DF
Plastic S-Pack 5-Pin
THERMAL RESISTANCE
-
JUNCTION TO
T
AB
,
θ
JT
3.0°C/W
THERMAL RESISTANCE
-
JUNCTION TO
A
MBIENT
,
θ
JA
35°C/W
Junction T emperature Calculation: T
J
= T
A
+ (P
D
x θ
JA
). θ
JA
assume device is mounted on a 0.5 i nch
2
copper pa d.
The θ
JA
numbers are guidelines for the thermal performance of the device/pc-board system. All of the above assume
no ambient airflow.
P
PA
AC
CK
KA
AG
GE
E
D
DA
AT
TA
A
Microsemi
Integrated Products Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 3
Copyright © 2001
Rev. 1.4b, 2005-05-04
WWW.Microsemi .COM
LX8580A
7.5A Ver
y
Low Dropout Positive Re
g
ulator
P
RODUCTION
D
ATA
S
HEET
TM ®
FUNCTIONAL PIN DESCRIPTION
P
IN
N
AME
D
ESCRIPTION
1 SENSE
This pin is the positive side of the reference voltage for the device. With this pin it is possible to Kelvin-sense the
output voltage at the load.
2 ADJUST
This pin is the negative side of the reference voltage for the device. Ripple rejection can be improved by adding
a small bypass capacitor from the ADJUST pin to ground. The capacitor value should be selected so that:
where F
R
is the ripple frequency and R
1
is the value of the resistor between the ADJUST and
SENSE leads of the LX8580A
3 OUTPUT This is the regulated power output of the device
4 V
CTRL
This pin is the voltage supply pin for the control circuitry of the device. The current flow into this pin will be about
1% of the output current. Please refer to the electrical characteristics section of
the data sheet for dropout voltage for load conditions.
5 V
PWR
This is the collector of the power section of the LX8580A. The o utput load current is supplied through this pin.
For the device to regulate, the voltage at this pin must be between 0.1V and 0.8V greater than the output voltage
(Higher output current require higher voltages differences between V
PWR
and OUTPUT).
TYPICAL APPLICATION
LX8580A
V
CTRL
V
PWR
OUTPUT
SENSE
ADJUST
5.0V
3.3V
Tantalum
100µF
Tantalum
33µF
V
OUT
= 2.8V
500µF
R
1
R
2
2ADJ
1
2
REFOUT RI
R
R
1VV ×+
⎟
⎟
⎠
⎞
⎜
⎜
⎝
⎛+=
R
1
= 12 1 Ω
R
2
= 15 0 Ω
P
PA
AC
CK
KA
AG
GE
E
D
DA
AT
TA
A
1R
R
RF2 1
Cπ
≤
Microsemi
Integrated Products Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 4
Copyright © 2001
Rev. 1.4b, 2005-05-04
WWW.Microsemi .COM
LX8580A
7.5A Ver
y
Low Dropout Positive Re
g
ulator
P
RODUCTION
D
ATA
S
HEET
TM ®
ELECTRICAL CHARACTERISTICS
Unless otherwise specified, the following specifications apply over the operating ambient temperature 0°C
≤
T
A
≤
125°C. Low duty cycle
pulse testing techniques are used which maintains junction and case temperatures are equal to the ambient temperature.
LX8580A
Parameter Symbol Test Conditions Min Typ Max
Units
V
CTRL
= 2.75V, V
PWR
= 2V, I
LOAD
= 10mA, T
A
=25°C1.243 1.250 1.257
V
CTRL
= 2.7V to 6V, V
PWR
= 1.75V to 5.5V
I
LOAD
= 10mA to 4A 1.237 1.250 1.263
Reference Voltage V
REF
V
CTRL
= 2.7V to 6V, V
PWR
= 2.05V to 5.5V
I
LOAD
= 10mA to 7.5A 1.237 1.250 1.263
V
V
CTRL
= 2.5V to 10V, V
PWR
= 1.75V to 5.5V
I
LOAD
= 10mA, T
A
=25°C 1 3 mV
Line Regulation ∆V
REF
(V
IN
) V
CTRL
= 2.5V to 10V, V
PWR
= 1.75V to 5.5V
I
LOAD
= 10mA 2 6 mV
Load Regulation ∆V
REF
(I
OUT
) V
CTRL
= 2.75V, V
PWR
= 2.1V I
LOAD
= 10mA to 7.5A
(V
ADJ
= 0) 2 7 mV
Thermal Regulation ∆V
OUT
(Pwr)
30ms Pulse 0.002 0.020 %/W
Thermal Resistance R
θJT
Control Circuitry/Power Transistor 0.65 2.70 °C/W
Ripple Rejection V
CTRL
= V
PWR
= 3.75V Avg, V
RIPPLE
= 1V
P-P
V
ADJ
= 0, I
OUT
= 4A 60 80 dB
V
CTRL
= 2.75V, V
PWR
= 2.05V, I
LOAD
= 100mA 3 10
V
CTRL
= 2.75V, V
PWR
= 2.05V, I
LOAD
= 3A 30 50
V
CTRL
= 2.75V, V
PWR
= 1.75V, I
LOAD
= 3A 33 55
V
CTRL
Pin Current (Note 2) I
CTRL
V
CTRL
= 2.75V, V
PWR
= 2.05V, I
LOAD
= 7.5A 70 120
mA
Adjust Pin Current I
ADJ
V
CTRL
= 2.75V, V
PWR
= 2.05V,
I
LOAD
= 0mA, V
ADJ
= 0 20 60 100
µA
Current Limit I
OUT(MAX)
V
CTRL
= 2.75V, V
PWR
= 2.05V, ∆V
OUT
= 100mV,
V
ADJ
= 0 7.7 9 A
V
PWR
= 2.05, I
LOAD
= 100mA 0.90 1.15
V
PWR
= 2.05, I
LOAD
= 1.5A 1.00 1.15
V
PWR
= 2.05, I
LOAD
= 3A 1.05 1.18
V
PWR
= 2.05, I
LOAD
= 5A 1.06 1.20
Dropout Voltage (Control Section)
Minimum V
CTRL
(Note 1)
(V
PWR
- V
OUT
) V
CTRL
-V
OUT
V
PWR
= 2.05, I
LOAD
= 7.5A 1.10 1.30
V
V
CTRL
= 2.75V, I
LOAD
= 100mA 0.03 0.05
V
CTRL
= 2.75V, I
LOAD
= 1.5A, T
A
= 85°C 0.10 0.13
V
CTRL
= 2.75V, I
LOAD
= 1.5A 0.13 0.15
V
CTRL
= 2.75V, I
LOAD
= 3A, T
A
= 85°C 0.20 0.25
V
CTRL
= 2.75V, I
LOAD
= 3A 0.25 0.28
V
CTRL
= 2.75V, I
LOAD
= 5A, T
A
= 85°C 0.38 0.43
V
CTRL
= 2.75V, I
LOAD
= 5A 0.40 0.45
V
CTRL
= 2.75V, I
LOAD
= 7.5A, T
A
= 85°C 0.52 0.65
Dropout Voltage (Power Section)
Minimum V
PWR
(Note 1)
(V
PWR
- V
OUT
)
(V
ADJ
= 0)
V
PWR
-V
OUT
V
CTRL
= 2.75V, I
LOAD
= 7.5A 0.59 0.70
V
Minimum Load Current V
CTRL
= 5V, V
PWR
= 3.3V, V
ADJ
= 0
Note 3 5 10 mA
Note 1: Dropout is caused by either minimum control voltage (V
CTRL
) or minimum power voltage (V
PWR
). Both parameters are specified with respect to
the output voltage. The specifications represent the minimum input/output voltage r equired to maintain 1% regulation.
Note 2: The control pin current is the drive current required f or the output transistor. This current will track output current with roughly a 1:100 ratio.
The minimum value is equal to the quiescent current of the device.
Note 3: Minimum load current is defined as the amount of output current required to maintain regulation. Typically this current provides the bias to the
external resistor divider network used to set the output voltage.
E
EL
LE
EC
CT
TR
RI
IC
CA
AL
LS
S
Microsemi
Integrated Products Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 5
Copyright © 2001
Rev. 1.4b, 2005-05-04
WWW.Microsemi .COM
LX8580A
7.5A Ver
y
Low Dropout Positive Re
g
ulator
P
RODUCTION
D
ATA
S
HEET
TM ®
SIMPLIFIED BLOCK DIAGRAM
V
REF
Voltage
Regulation
Amplifier
Thermal Overload
Current
Limiting
Amplifier OUTPUT
V
PWR
SENSE
ADJUST
V
CTRL
B
BL
LO
OC
CK
K
D
DI
IA
AG
GR
RA
AM
M
Microsemi
Integrated Products Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 6
Copyright © 2001
Rev. 1.4b, 2005-05-04
WWW.Microsemi .COM
LX8580A
7.5A Ver
y
Low Dropout Positive Re
g
ulator
P
RODUCTION
D
ATA
S
HEET
TM ®
CHARACTERISTIC CURVES
Reference Voltage vs. Temperature
1.2500
1.2505
1.2510
1.2515
1.2520
1.2525
1.2530
0255075100125
T
J
(°C)
V
REF
(VOLTS)
Load Regulation vs. Output Current
0.00
0.05
0.10
0.15
0.20
012345678
Output Current (A)
Output Voltage Deviation(%)
V
CTRL
Dropout, VPWR=3.25V
1.00
1.02
1.04
1.06
1.08
1.10
1.12
02468
Output Current (A)
V
CTRL
Dropout (V)
VPWR Dropout Voltage vs. IOUT
0.0
0.1
0.2
0.3
0.4
0.5
0.6
012345678
Power Dropout (V)
IOUT (A)
125°C
85°C
0°C
Transient Response
Ripple Rejection
10
20
30
40
50
60
70
80
90
100
100 1000 10000 100000
Frequency (Hz)
Ripple Rejection (dB
)
Vout=1.25V
Vin=3.3V
Vripple=1Vpp
Cout=820uF electrolytic
+2.2uF ceramic
Cadj= 0 uF
G
GR
RA
AP
PH
HS
S
Microsemi
Integrated Products Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 7
Copyright © 2001
Rev. 1.4b, 2005-05-04
WWW.Microsemi .COM
LX8580A
7.5A Ver
y
Low Dropout Positive Re
g
ulator
P
RODUCTION
D
ATA
S
HEET
TM ®
PACKAGE DIMENSIONS
P
5-Pin Plastic TO-220
A
G
F
B
D
C
J
R
K
N
S
T
15
M
ILLIMETERS INCHES
Dim MIN MAX MIN MAX
A 14.23 16.51 0.560 0.650
B 9.66 10.66 0.380 0.420
C 3.56 4.82 0.140 0.190
D 0.46 0.89 0.018 0.035
F 3.56 4.06 0.140 0.160
G 3.40 0.134
J 0.31 1.14 0.012 0.045
K 12.70 14.73 0.500 0.580
N 6.80 TYP 0.268 TYP
R 2.04 2.92 0.080 0.115
S 1.14 1.39 0.045 0.055
T 5.85 6.85 0.230 0.270
DD
5-Pin Plastic TO-263
A
B
K
I
F
H
C
D
0° -8°
M
N
J
Seating Plane
E
G
M
ILLIMETERS INCHES
Dim MIN MAX MIN MAX
A 10.03 10.67 0.395 0.420
B 8.51 9.17 0.335 0.361
C 4.19 4.59 0.165 0.181
D 1.14 1.40 0.045 0.055
E 0.330 0.51 0.013 0.020
F 0.74 0.89 0.029 0.035
G 1.57 1.83 0.062 0.072
H 2.29 2.79 0.090 0.110
I – 1.65 – 0.065
J 0 0.25 0 0.010
K 14.60 15.87 0.575 0.625
M 7° 7°
N 3° 3°
M
M
E
EC
CH
HA
AN
NI
IC
CA
AL
LS
S
Microsemi
Integrated Products Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 8
Copyright © 2001
Rev. 1.4b, 2005-05-04
WWW.Microsemi .COM
LX8580A
7.5A Ver
y
Low Dropout Positive Re
g
ulator
P
RODUCTION
D
ATA
S
HEET
TM ®
PACKAGE DIMENSIONS
DF
5-Pin Plastic S-Pak
A
BK
F G
J
H
C
E
I
D
L
M
M
ILLIMETERS INCHES
Dim MIN MAX MIN MAX
A 9.27 9.52 0.365 0.375
B 7.87 8.13 0.310 0.320
C 1.78 2.03 0.070 0.080
D 8.03 BSC 0.316 BSC
E 0.25 BSC 0.010 BSC
F 0.63 0.79 0.025 0.031
G 1.70 BSC 0.067 BSC
H 0.79 1.04 0.031 0.041
I 6.50 BSC 0.256 BSC
J 0.03 0.13 0.001 0.005
K 10.41 10.67 0.410 0.420
L 0.25 BSC 0.01 BSC
M 0.76 1.27 0.03 0.05
Note:
Dimensions do not include mold flash or protrusions; these shall not exceed 0.155mm(.0 06”) on any side. Lead dimension shall
not include solder coverage.
M
ME
EC
CH
HA
AN
NI
IC
CA
AL
LS
S
Microsemi
Integrated Products Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 9
Copyright © 2001
Rev. 1.4b, 2005-05-04
WWW.Microsemi .COM
LX8580A
7.5A Ver
y
Low Dropout Positive Re
g
ulator
P
RODUCTION
D
ATA
S
HEET
TM ®
NOTES
PRODUCTION DATA – Information contained in this document is proprietary to
Microsemi and is current as of publication date. This document may not be modified in
any way without the express written consent of Microsemi. Product processing does not
necessarily include testing of all parameters. Microsemi reserves the right to change the
configuration and performance of th e product an d to discontinue product at any time.
N
NO
OT
TE
ES
S
