Microsemi
Linfinity Microelectronics Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 1
Copyright 2001
Rev. 1.4, 2003-01-06
WWW.Microsemi .COM
LX8580A
7.5A Ver
y
Low Dropout Positive Re
g
ulator
P
RODUCTION
D
ATA
S
HEET
INTEGRATED PRODUCTS
DESCRIPTION
The LX8580A is a high-
performance, very low dropout voltage
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 for generating 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
VCTRL ≥ V OUT + 1.3V Max VOUT
VPW R ≥ V OUT + VDROPOUT
LX8580A
VPWR
VCTRL
4
1
3
2
5ADJUST
SENSE
OUTPUT
R1
R2
RL
2
1
2
1RI
R
R
VV ADJREFOUT ×+
+=
PACKAGE ORDER INFO
TA (°C) DROPOUT
VOLTAGE P Plastic TO-220
5-Pin DF S-PAK
5-pin DD Plastic TO-263
5-PIN
0 to 125 0.1V – 0.7V LX8580A-00CP LX8580A-00CDF LX8580A-00CDD
Note: Available in Tape & Reel.
Append the letter “T” to the part number. (i.e. LX8580A-00CDDT)
L
LX
X8
85
58
80
0A
A
Microsemi
Linfinity Microelectronics Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 2
Copyright 2001
Rev. 1.4, 2003-01-06
WWW.Microsemi .COM
LX8580A
7.5A Ver
y
Low Dropout Positive Re
g
ulator
P
RODUCTION
D
ATA
S
HEET
INTEGRATED PRODUCTS
ABSOLUTE MAXIMUM RATINGS
V
CTRL Input Voltage.........................................................................................13V
VPWR 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
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 PACKAGE (5-PIN)
(Top View)
1
2
3
TAB is OUTPUT
4
5
OUTPUT
VPWR
VCTRL
ADJUST
SENSE
DD PACKAGE (5-PIN)
(Top View)
1SENSE
OUTPUT
VPWR
2
3
TAB is OUTPUT
4
5VCTRL
ADJUST
DF PACKAGE
(Top Vi ew)
TAB is OUTPUT
1SENSE
ADJUST
OUTPUT
VCTRL
VPWR
2
3
4
5
THERMAL DATA
P Plastic TO-220 5-Pin
THERMAL RESISTANCE-JUNCTION TO TAB, θJT 3.0°C/W
THERMAL RESISTANCE-JUNCTION TO AMBIENT, θJA 65°C/W
DD Plastic TO-263 5-Pin
THERMAL RESISTANCE-JUNCTION TO TAB, θJT 3.0°C/W
THERMAL RESISTANCE-JUNCTION TO AMBIENT, θJA 35°C/W
DF Plastic S-Pack 5-Pin
THERMAL RESISTANCE-JUNCTION TO TAB, θJT 3.0°C/W
THERMAL RESISTANCE-JUNCTION TO AMBIENT, θJA 35°C/W
Junction Temperature Calculation: TJ = TA + (PD x θJA). θJA assume device is mounted
on a 0.5 inch2 copper pad. The θJA numbers are guidelines for the thermal performance of
the device/pc-board system. All of the above assume no ambient airflow.
FUNCTIONAL PIN DESCRIPTION
PIN NAME DESCRIPTION
1 SENSE This pin is the positive side of the reference voltage for the device. With this pin it is pos sible to
Kelvin-sense the output voltage at the lo ad.
2 ADJUST
This pin is the negative side of the reference voltage for the device. Ripple rejectio n can be
improved by adding a small bypass capacito r from the ADJUST pin to ground. The capacitor value
should be selected so that:
where FR is the ripple frequency and R1 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 VCTRL This pin is the voltage supply pin for the co ntrol circuitry of the device. The current flow into this pin
will be about 1% of the output current. Please refer to the electrical charact eristics section of
the data sheet for dropout voltage for load co nditions.
5 VPWR
This is the collector of the power section of the LX8580A. The output 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
VPWR and OUTPUT).
P
PA
AC
CK
KA
AG
GE
E
D
DA
AT
TA
A
1R
RRF2 1
Cπ
≤
Microsemi
Linfinity Microelectronics Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 3
Copyright 2001
Rev. 1.4, 2003-01-06
WWW.Microsemi .COM
LX8580A
7.5A Ver
y
Low Dropout Positive Re
g
ulator
P
RODUCTION
D
ATA
S
HEET
INTEGRATED PRODUCTS
ELECTRICAL CHARACTERISTICS
Unless otherwise specified, the following specifications apply over the operating ambient temperature 0°C≤ TA≤ 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
VCTRL = 2.75V, VPWR = 2V, ILOAD = 10mA, TA=25°C1.243 1.250 1.257
VCTRL = 2.7V to 6V, VPWR = 1.75V to 5.5V
ILOAD = 10mA to 4A 1.237 1.250 1.263
Reference Voltage VREF
VCTRL = 2.7V to 6V, VPWR = 2.05V to 5.5V
ILOAD = 10mA to 7.5A 1.237 1.250 1.263
V
VCTRL = 2.5V to 10V, VPWR = 1.75V to 5.5V
ILOAD = 10mA, TA=25°C 1 3 mV
Line Regulation ∆VREF(VIN) VCTRL = 2.5V to 10V, VPWR = 1.75V to 5.5V
ILOAD = 10mA 2 6 mV
Load Regulation ∆VREF(IOUT) VCTRL = 2.75V, VPWR = 2.1V ILOAD = 10mA to 7.5A
(VADJ = 0) 2 7 mV
Thermal Regulation ∆VOUT(Pwr) 30ms Pulse 0.002 0.020 %/W
Thermal Resistance RθJT Control Circuitry/Power Transistor 0.65 2.70 °C/W
Ripple Rejection VCTRL = VPWR = 3.75V Avg, VRIPPLE = 1VP-P
VADJ = 0, IOUT = 4A 60 80 dB
VCTRL = 2.75V, VPWR = 2.05V, ILOAD = 100mA 3 10
VCTRL = 2.75V, VPWR = 2.05V, ILOAD = 3A 30 50
VCTRL = 2.75V, VPWR = 1.75V, ILOAD = 3A 33 55
V
CTRL Pin Current (Note 2) ICTRL
VCTRL = 2.75V, VPWR = 2.05V, ILOAD = 7.5A 70 120
mA
Adjust Pin Current IADJ VCTRL = 2.75V, VPWR = 2.05V,
ILOAD = 0mA, VADJ = 0 20 60 100
µA
Current Limit IOUT(MAX) VCTRL = 2.75V, VPW R = 2.05V, ∆VOUT = 100mV,
VADJ = 0 7.7 9 A
VPWR = 2.05, ILOAD = 100mA 0.90 1.15
VPWR = 2.05, ILOAD = 1.5A 1.00 1.15
VPWR = 2.05, ILOAD = 3A 1.05 1.18
VPWR = 2.05, ILOAD = 5A 1.06 1.20
Dropout Voltage (Control Section)
Minimum VCTRL (Note 1)
(VPWR - VOUT) VCTRL-VOUT
VPWR = 2.05, ILOAD = 7.5A 1.10 1.30
V
VCTRL = 2.75V, ILOAD = 100mA 0.03 0.05
VCTRL = 2.75V, ILOAD = 1.5A, TA = 85°C 0.10 0.13
VCTRL = 2.75V, ILOAD = 1.5A 0.13 0.15
VCTRL = 2.75V, ILOAD = 3A, TA = 85°C 0.20 0.25
VCTRL = 2.75V, ILOAD = 3A 0.25 0.28
VCTRL = 2.75V, ILOAD = 5A, TA = 85°C 0.38 0.43
VCTRL = 2.75V, ILOAD = 5A 0.40 0.45
VCTRL = 2.75V, ILOAD = 7.5A, TA = 85°C 0.52 0.65
Dropout Voltage (Power Section)
Minimum VPWR (Note 1)
(VPWR - VOUT)
(VADJ = 0)
VPWR-VOUT
VCTRL = 2.75V, ILOAD = 7.5A 0.59 0.70
V
Minimum Load Current VCTRL = 5V, VPWR = 3.3V, VADJ = 0
Note 3 5 10 mA
Note 1: Dropout is caused by either minimum control voltage (VCTRL) or minimum power voltage (VPWR). 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 c urrent required for 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
Linfinity Microelectronics Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 4
Copyright 2001
Rev. 1.4, 2003-01-06
WWW.Microsemi .COM
LX8580A
7.5A Ver
y
Low Dropout Positive Re
g
ulator
P
RODUCTION
D
ATA
S
HEET
INTEGRATED PRODUCTS
SIMPLIFIED BLOCK DIAGRAM
VREF
Voltage
Regulation
Amplifier
T he rm al Ov erlo a d
Current
Limiting
Amplifier OUTPUT
VPWR
SENSE
ADJUST
VCTRL
TYPICAL APPLICATION
LX8580A
VCTRL
VPWR
OUTPUT
SENSE
ADJUST
5.0V
3.3V
Tantalum
100µF
Tantalum
33µF
VOUT = 2.8V
500µF
R1
R2
2ADJ
1
2
REFOUT RI
R
R
1VV ×+
+=
R1 = 121 Ω
R2 = 150 Ω
B
BL
LO
OC
CK
K
D
DI
IA
AG
GR
RA
AM
M
Microsemi
Linfinity Microelectronics Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page
5
Copyright 2001
Rev. 1.4, 2003-01-06
WWW.Microsemi .COM
LX8580A
7.5A Ver
y
Low Dropout Positive Re
g
ulator
P
RODUCTION
D
ATA
S
HEET
INTEGRATED PRODUCTS
CHARACTERISTIC CURVES
Reference Voltage vs. Temperature
1.2500
1.2505
1.2510
1.2515
1.2520
1.2525
1.2530
0255075100125
TJ(°C)
VREF(VOLTS)
Load Regulation vs. Output Current
0.00
0.05
0.10
0.15
0.20
012345678
Output Current (A)
Output Voltage Deviation(%)
VCTRL Dropout, VPWR=3.25V
1.00
1.02
1.04
1.06
1.08
1.10
1.12
02468
Output Current (A)
VCTRL 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
Linfinity Microelectronics Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 6
Copyright 2001
Rev. 1.4, 2003-01-06
WWW.Microsemi .COM
LX8580A
7.5A Ver
y
Low Dropout Positive Re
g
ulator
P
RODUCTION
D
ATA
S
HEET
INTEGRATED PRODUCTS
PACKAGE DIMENSIONS
P 5-Pin Plastic TO-220
A
G
F
B
D
C
J
R
K
N
S
T
15
MILLIMETERS 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
Seatin g Plane
E
G
MILLIMETERS 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
ME
EC
CH
HA
AN
NI
IC
CA
AL
LS
S
Microsemi
Linfinity Microelectronics Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page
7
Copyright 2001
Rev. 1.4, 2003-01-06
WWW.Microsemi .COM
LX8580A
7.5A Ver
y
Low Dropout Positive Re
g
ulator
P
RODUCTION
D
ATA
S
HEET
INTEGRATED PRODUCTS
PACKAGE DIMENSIONS
DF 5-Pin Plastic S-Pak
A
BK
FG
J
H
C
E
I
D
MILLIMETERS 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 2.80 3.10 0.110 0.122
E 1.50 1.75 0.059 0.069
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
Note: Dimensions do not include mold flash or protrusions; these shall not exceed 0.155mm(.006”) on any side. Lead dimension shall
not include solder coverage.
M
ME
EC
CH
HA
AN
NI
IC
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Microsemi
Linfinity Microelectronics Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page
8
Copyright 2001
Rev. 1.4, 2003-01-06
WWW.Microsemi .COM
LX8580A
7.5A Ver
y
Low Dropout Positive Re
g
ulator
P
RODUCTION
D
ATA
S
HEET
INTEGRATED PRODUCTS
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 the product and to discontinue product at any time.
N
NO
OT
TE
ES
S
