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Reliability
Obsolete
Features
Available in 3.3V, 5.0V, 12V and Adjustable Versions
Current Limiting and Thermal Protection
Output Current
5A
Industrial Temperature Range
-40°C to 125°C
Line Regulation
0.015% (typical)
Load Regulation
0.1% (typical)
Description
The LM1084 is a series of low dropout voltage positive regulators with a maximum dropout of 1.5V at 5A of load current. It has the same pin-out as National Semiconductor's industry standard LM317.
The LM1084 is available in an adjustable version, which can set the output voltage with only two external resistors. It is also available in three fixed voltages: 3.3V, 5.0V and 12.0V. The fixed versions intergrate the adjust resistors.
The LM1084 circuit includes a zener trimmed bandgap reference, current limiting and thermal shutdown.
The LM1084 series is available in TO-220 and TO-263 packages. Refer to the LM1085 for the 3A version, and the LM1086 for the 1.5A version.
Applications
Post Regulator for Switching DC/DC Conveter
High Efficiency Linear Regulators
Battery Charger
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LM1085▲ 3A Version
LM1086▲ 1.5A Version
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LM1085▲ 3A Version
LM1086▲ 1.5A Version
Paramaters / Values LM1084 LM1085 LM1086
Output Current 5000 mA
3000 mA
1500 mA
Output Min 1.25, 3.3, 5 Volt
3.3, 1.25, 12, 5 Volt
3.3, 1.25, 5, 2.5 Volt
Input Min Voltage 2.6 Volt
2.6 Volt
2.6 Volt
Input Max Voltage 25, 27, 29 Volt
25, 27, 18, 29 Volt
27, 25, 30, 29 Volt
Dropout Voltage 1.3 Volt
1.3 Volt
1.3 Volt
Adjustable Output No
No
No
Quiescent Current 5 mA
5 mA
2 mA
On/Off Pin No
No
No
Error Flag No
No
No
RegType LDO
LDO
LDO
Temperature Min -40 deg C
-40 deg C
-40 deg C
Temperature Max 125 deg C
125 deg C
125 deg C
Output Max 3.3, 27.5, 5 Volt
3.3, 27.5, 12, 5 Volt
3.3, 27.5, 5, 2.5 Volt
Output Voltage 3.3, 5 Volt
3.3, 12, 5 Volt
3.3, 5, 2.5 Volt
Datasheet
Featured Application Notes
More Application Notes
Part Number(s) (NSID) Top View Availability Current Reported Stock Budgetary Pricing Standard Pack Size
LM1084IT-3.3/NOPB LM1084IT-3.3RoHS
Full production Lead Time: 8 weeks
$1.41 each at 1K+ pcs rail of 45
LM1084IT-5.0/NOPB LM1084IT-5.0RoHS
Full production Lead Time: 8 weeks
$1.41 each at 1K+ pcs rail of 45
LM1084IT-ADJ/NOPB LM1084IT-ADJRoHS
Full production Lead Time: 12 weeks
$1.41 each at 1K+ pcs rail of 45
LM1084IS-12/NOPBRoHS
Lifetime buy Lead Time: 8 weeks
$1.40 each at 1K+ pcs rail of 45
LM1084IS-3.3/NOPB LM1084IS-3.3RoHS
Full production Lead Time: 8 weeks
$1.40 each at 1K+ pcs rail of 45
LM1084IS-5.0/NOPB LM1084IS-5.0RoHS
Full production Lead Time: 8 weeks
$1.40 each at 1K+ pcs rail of 45
LM1084IS-ADJ/NOPB LM1084IS-ADJRoHS
Full production Lead Time: 8 weeks
$1.40 each at 1K+ pcs rail of 45
LM1084ISX-12/NOPBRoHS
Lifetime buy Lead Time: 8 weeks Distributor Region Qty
DIGIKEY Worldwide 0
$1.40 each at 1K+ pcs reel of 500
LM1084ISX-3.3/NOPB LM1084ISX-3.3RoHS
Full production Lead Time: 8 weeks
$1.40 each at 1K+ pcs reel of 500
LM1084ISX-5.0/NOPB LM1084ISX-5.0RoHS
Full production Lead Time: 8 weeks
$1.40 each at 1K+ pcs reel of 500
LM1084ISX-ADJ/NOPB LM1084ISX-ADJRoHS
Full production Lead Time: 12 weeks
$1.40 each at 1K+ pcs reel of 500
Obsolete Versions
Obsolete Part Alternate Part or
Supplier Source Last Time Buy Date
LM1084IS-12 LM1084IS-ADJ NATIONAL SEMICONDUCTOR 01 Dec 2009
LM1084ISX-12 LM1084IS-ADJ NATIONAL SEMICONDUCTOR 01 Dec 2009
LM1084IT-12 NONE NATIONAL SEMICONDUCTOR 16 Nov 2008
Reliability Metrics
Part Number
Process
EFR Reject
EFR Sample Size
PPM
LTA Rejects
LTA Device Hours
FITS
MTTF (Hours)
LM1084IS-12 LB300 0 33664 0 0 3830500 1 1086914834
LM1084IS-3.3 LB300 0 33664 0 0 3830500 1 1086914834
LM1084IS-5.0 LB300 0 33664 0 0 3830500 1 1086914834
LM1084IS-ADJ LB300 0 33664 0 0 3830500 1 1086914834
LM1084ISX-12 LB300 0 33664 0 0 3830500 1 1086914834
LM1084ISX-3.3 LB300 0 33664 0 0 3830500 1 1086914834
LM1084ISX-5.0 LB300 0 33664 0 0 3830500 1 1086914834
LM1084ISX-ADJ LB300 0 33664 0 0 3830500 1 1086914834
LM1084IT-12 LB300 0 33664 0 0 3830500 1 1086914834
LM1084IT-3.3 LB300 0 33664 0 0 3830500 1 1086914834
LM1084IT-5.0 LB300 0 33664 0 0 3830500 1 1086914834
LM1084IT-ADJ LB300 0 33664 0 0 3830500 1 1086914834
Note: The Early Failure Rates (EFR) were calculated as point estimate PPM based on rejects and sample size for EFR.
The Long Term Failure Rates were calculated
at 60% confidence using the Arrhenius equation at 0.7eV activation energy and derating the assumed stress
temperature of 150°C to an application temperature of 55°C.
For more information on Reliability Metrics, please click
here .
Obsolete Versions
Obsolete Part Alternate Part or
Supplier Source Last Time Buy Date
LM1084IS-12 LM1084IS-ADJ NATIONAL SEMICONDUCTOR 01 Dec 2009
LM1084ISX-12 LM1084IS-ADJ NATIONAL SEMICONDUCTOR 01 Dec 2009
LM1084IT-12 NONE NATIONAL SEMICONDUCTOR 16 Nov 2008