lx8580a.pdf

LX8580A
7.5A Very Low Dropout Positive Regulator
®
TM
P RODUCTION D ATA S HEET
KEY FEATURES
DESCRIPTION
ƒ Low Dropout, 650mV at 7.5A
Output Current in Dual Supply
Mode
ƒ Fast Transient Response
ƒ Remote Sensing
ƒ 1mV Load Regulation
ƒ Adjustable Output
similar to that of the LX8584 (1.3V @
7.5A).
The LX8580A is supplied in a fiveterminal 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.
APPLICATIONS/BENEFITS
ƒ Microprocessor/Micro controller
Supplies
ƒ 3.3V to 2.85V Voltage
Conversion
ƒ High-Current Regulators
ƒ Post Regulation for Switching
Power Supplies
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The
LX8580A
is
a
highperformance, 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
IMPORTANT: For the most current data, consult MICROSEMI’s website: http://www.microsemi.com
PRODUCT HIGHLIGHT
4
V CTR L ≥ V OU T + 1.3V Max
V CT RL
OUTPUT
3
V OUT
LX8580A
V PW R ≥ V OU T + V DR OPOUT
5
V PW R
SENSE
ADJUST
1
R1
2
RL
⎛
VOUT = VREF ⎜⎜ 1 +
⎝
R2
R2 ⎞
⎟
+ I ADJ × R 2
R 1 ⎟⎠
DROPOUT
VOLTAGE
0 to 125
0.1V – 0.7V
P
DD
LX8580A
TA (°C)
PACKAGE ORDER INFO
Plastic TO-220
S-PAK
DF 5-pin
5-Pin
Plastic TO-263
5-PIN
RoHS Compliant
Transition DC: 0515
LX8580A-00CP
LX8580A-00CDF
LX8580A-00CDD
Note: Available in Tape & Reel. Append the letters “TR” to the part number. (i.e. LX8580A-00CDD-TR)
Copyright © 2001
Rev. 1.4b, 2005-05-04
Microsemi
Integrated Products Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 1
LX8580A
®
TM
7.5A Very Low Dropout Positive Regulator
P RODUCTION D ATA S HEET
ABSOLUTE MAXIMUM RATINGS
PACKAGE PIN OUT
TAB is OUTPUT
5
VPWR
4
VCTRL
3
OUTPUT
2
ADJUST
1
SENSE
P PACKAGE (5-PIN)
(Top View)
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.
TAB is OUTPUT
THERMAL DATA
P
Plastic TO-220 5-Pin
THERMAL RESISTANCE-JUNCTION TO TAB, θJT
THERMAL RESISTANCE-JUNCTION TO AMBIENT, θJA
DD
3.0°C/W
65°C/W
5
VPWR
4
VCTRL
3
OUTPUT
2
ADJUST
1
SENSE
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VCTRL 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
DD PACKAGE (5-PIN)
(Top View)
Plastic TO-263 5-Pin
TAB is OUTPUT
THERMAL RESISTANCE-JUNCTION TO TAB, θJT
THERMAL RESISTANCE-JUNCTION TO AMBIENT, θJA
3.0°C/W
35°C/W
DF
Plastic S-Pack 5-Pin
THERMAL RESISTANCE-JUNCTION TO TAB, θJT
THERMAL RESISTANCE-JUNCTION TO AMBIENT, θJA
3.0°C/W
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.
5
VPWR
4
VCTRL
3
OUTPUT
2
ADJUST
1
SENSE
DF PACKAGE
(Top View)
RoHS 100% Matte Tin Lead Finish
PACKAGE DATA
Copyright © 2001
Rev. 1.4b, 2005-05-04
Microsemi
Integrated Products Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 2
LX8580A
®
TM
7.5A Very Low Dropout Positive Regulator
P RODUCTION D ATA S HEET
PIN
NAME
1
SENSE
DESCRIPTION
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.
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:
2
ADJUST
CR ≤
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
1
2πFRR1
This is the regulated power output of the device
4
VCTRL
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
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).
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FUNCTIONAL PIN DESCRIPTION
TYPICAL APPLICATION
5.0V
Tantalum
33µF
VCTRL
VOUT = 2.8V
OUTPUT
⎛ R ⎞
VOUT = VREF ⎜⎜1+ 2 ⎟⎟ + IADJ × R 2
⎝ R1 ⎠
SENSE
LX8580A
R1
500µF
3.3V
VPWR
ADJUST
R2
R1 = 121Ω
R2 = 150Ω
Tantalum
100µF
PACKAGE DATA
Copyright © 2001
Rev. 1.4b, 2005-05-04
Microsemi
Integrated Products Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 3
LX8580A
®
TM
7.5A Very Low Dropout Positive Regulator
P RODUCTION D ATA S HEET
Parameter
Symbol
Test Conditions
VCTRL = 2.75V, VPWR = 2V, ILOAD = 10mA, TA=25°C
Reference Voltage
VREF
∆VREF(VIN)
Line Regulation
Load Regulation
∆VREF(IOUT)
Thermal Regulation
Thermal Resistance
∆VOUT(Pwr)
RθJT
Ripple Rejection
VCTRL Pin Current (Note 2)
ICTRL
Adjust Pin Current
IADJ
Current Limit
IOUT(MAX)
Dropout Voltage (Control Section)
Minimum VCTRL (Note 1)
(VPWR - VOUT)
VCTRL-VOUT
Dropout Voltage (Power Section)
Minimum VPWR (Note 1)
(VPWR - VOUT)
(VADJ = 0)
VPWR-VOUT
LX8580A
Typ
Max
Units
1.243
1.250
1.257
1.237
1.250
1.263
1.237
1.250
1.263
1
3
mV
2
6
mV
2
7
mV
0.002
0.65
0.020
2.70
%/W
°C/W
60
80
V
dB
3
30
33
70
10
50
55
120
mA
20
60
100
µA
7.7
9
A
0.90
1.00
1.05
1.06
1.10
0.03
0.10
0.13
0.20
0.25
0.38
0.40
0.52
0.59
1.15
1.15
1.18
1.20
1.30
0.05
0.13
0.15
0.25
0.28
0.43
0.45
0.65
0.70
5
10
V
V
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 required to maintain 1% regulation.
Note 2: The control pin current is the drive current 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.
Copyright © 2001
Rev. 1.4b, 2005-05-04
Microsemi
Integrated Products Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 4
ELECTRICALS
Minimum Load Current
VCTRL = 2.7V to 6V, VPWR = 1.75V to 5.5V
ILOAD = 10mA to 4A
VCTRL = 2.7V to 6V, VPWR = 2.05V to 5.5V
ILOAD = 10mA to 7.5A
VCTRL = 2.5V to 10V, VPWR = 1.75V to 5.5V
ILOAD = 10mA, TA=25°C
VCTRL = 2.5V to 10V, VPWR = 1.75V to 5.5V
ILOAD = 10mA
VCTRL = 2.75V, VPWR = 2.1V ILOAD = 10mA to 7.5A
(VADJ = 0)
30ms Pulse
Control Circuitry/Power Transistor
VCTRL = VPWR = 3.75V Avg, VRIPPLE = 1VP-P
VADJ = 0, IOUT = 4A
VCTRL = 2.75V, VPWR = 2.05V, ILOAD = 100mA
VCTRL = 2.75V, VPWR = 2.05V, ILOAD = 3A
VCTRL = 2.75V, VPWR = 1.75V, ILOAD = 3A
VCTRL = 2.75V, VPWR = 2.05V, ILOAD = 7.5A
VCTRL = 2.75V, VPWR = 2.05V,
ILOAD = 0mA, VADJ = 0
VCTRL = 2.75V, VPWR = 2.05V, ∆VOUT = 100mV,
VADJ = 0
VPWR = 2.05, ILOAD = 100mA
VPWR = 2.05, ILOAD = 1.5A
VPWR = 2.05, ILOAD = 3A
VPWR = 2.05, ILOAD = 5A
VPWR = 2.05, ILOAD = 7.5A
VCTRL = 2.75V, ILOAD = 100mA
VCTRL = 2.75V, ILOAD = 1.5A, TA = 85°C
VCTRL = 2.75V, ILOAD = 1.5A
VCTRL = 2.75V, ILOAD = 3A, TA = 85°C
VCTRL = 2.75V, ILOAD = 3A
VCTRL = 2.75V, ILOAD = 5A, TA = 85°C
VCTRL = 2.75V, ILOAD = 5A
VCTRL = 2.75V, ILOAD = 7.5A, TA = 85°C
VCTRL = 2.75V, ILOAD = 7.5A
VCTRL = 5V, VPWR = 3.3V, VADJ = 0
Note 3
Min
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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
TM
®
7.5A Very Low Dropout Positive Regulator
P RODUCTION D ATA S HEET
SIMPLIFIED BLOCK DIAGRAM
WWW . Microsemi .C OM
VCTRL
V PW R
Current
Limiting
Amplifier
O UTPUT
Thermal O verload
Voltage
Regulation
Amplifier
SENSE
V R EF
ADJUST
BLOCK DIAGRAM
Copyright © 2001
Rev. 1.4b, 2005-05-04
Microsemi
Integrated Products Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 5
LX8580A
7.5A Very Low Dropout Positive Regulator
®
TM
P RODUCTION D ATA S HEET
Load Regulation vs. Output Current
Output Voltage Deviation(%)
Reference Voltage vs. Temperature
1.2530
V REF(VOLTS)
1.2525
1.2520
1.2515
1.2510
1.2505
1.2500
0
25
50
75
100
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CHARACTERISTIC CURVES
0.20
0.15
0.10
0.05
0.00
0
125
1
2
TJ (°C)
3
4
5
6
7
8
Output Current (A)
VPWR Dropout Voltage vs. IOUT
VCTRL Dropout, VPWR=3.25V
1.12
125°C
0.5
85°C
1.08
IOUT (A)
V CTRL Dropout (V)
0.6
1.10
1.06
1.04
1.02
0.4
0.3
0°C
0.2
0.1
1.00
0
2
4
6
0.0
8
0
1
2
Output Current (A)
3
4
5
6
7
8
Pow er Dropout (V)
Ripple Rejection
Transient Response
Ripple Rejection (dB)
100
90
80
70
60
50
Vout=1.25V
Vin=3.3V
40
Vripple=1Vpp
30
Cout=820uF electrolytic
20
+2.2uF ceramic
Cadj= 0 uF
10
100
1000
10000
100000
GRAPHS
Frequency (Hz)
Copyright © 2001
Rev. 1.4b, 2005-05-04
Microsemi
Integrated Products Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 6
LX8580A
7.5A Very Low Dropout Positive Regulator
®
TM
P RODUCTION D ATA S HEET
P
WWW . Microsemi .C OM
PACKAGE DIMENSIONS
5-Pin Plastic TO-220
B
Dim
S
F
T
A
B
C
D
F
G
J
K
N
R
S
T
A
1
C
5
R
K
D
J
G
N
DD
MILLIMETERS
MIN
MAX
14.23
16.51
9.66
10.66
3.56
4.82
0.46
0.89
3.56
4.06
3.40
0.31
1.14
12.70
14.73
6.80 TYP
2.04
2.92
1.14
1.39
5.85
6.85
INCHES
MIN
MAX
0.560
0.650
0.380
0.420
0.140
0.190
0.018
0.035
0.140
0.160
0.134
0.012
0.045
0.500
0.580
0.268 TYP
0.080
0.115
0.045
0.055
0.230
0.270
MILLIMETERS
MIN
MAX
10.03
10.67
8.51
9.17
4.19
4.59
1.14
1.40
0.330
0.51
0.74
0.89
1.57
1.83
2.29
2.79
–
1.65
0
0.25
14.60
15.87
7°
3°
INCHES
MIN
MAX
0.395
0.420
0.335
0.361
0.165
0.181
0.045
0.055
0.013
0.020
0.029
0.035
0.062
0.072
0.090
0.110
–
0.065
0
0.010
0.575
0.625
7°
3°
5-Pin Plastic TO-263
I
A
D
Dim
C
B
K
M
N
H
0° -8°
E
G
MECHANICALS
F
A
B
C
D
E
F
G
H
I
J
K
M
N
J
Seating Plane
Copyright © 2001
Rev. 1.4b, 2005-05-04
Microsemi
Integrated Products Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 7
LX8580A
7.5A Very Low Dropout Positive Regulator
®
TM
P RODUCTION D ATA S HEET
DF
WWW . Microsemi .C OM
PACKAGE DIMENSIONS
5-Pin Plastic S-Pak
A
M
C
I
L
D
B
K
H
J
F
G
E
Dim
A
B
C
D
E
F
G
H
I
J
K
L
M
INCHES
MIN
MAX
0.365
0.375
0.310
0.320
0.070
0.080
0.316 BSC
0.010 BSC
0.025
0.031
0.067 BSC
0.031
0.041
0.256 BSC
0.001
0.005
0.410
0.420
0.01 BSC
0.03
0.05
MECHANICALS
Note:
MILLIMETERS
MIN
MAX
9.27
9.52
7.87
8.13
1.78
2.03
8.03 BSC
0.25 BSC
0.63
0.79
1.70 BSC
0.79
1.04
6.50 BSC
0.03
0.13
10.41
10.67
0.25 BSC
0.76
1.27
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.
Copyright © 2001
Rev. 1.4b, 2005-05-04
Microsemi
Integrated Products Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 8
LX8580A
TM
®
7.5A Very Low Dropout Positive Regulator
P RODUCTION D ATA S HEET
WWW . Microsemi .C OM
NOTES
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.
Copyright © 2001
Rev. 1.4b, 2005-05-04
Microsemi
Integrated Products Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 9