Product overview
Description
The LD2981 is a 100 mA fixed-output voltage regulator. The low-drop voltage and the ultra low quiescent current make them suitable for low noise, low power applications and in battery powered systems.
The quiescent current in sleep mode is less than 1 μA when INHIBIT pin is pulled low. Shutdown logic control function is available on pin n° 3 (TTL compatible). This means that when the device is used as local regulator, it is possible to put a part of the board in standby, decreasing the total power consumption. The LD2981 is designed to work with low ESR ceramic capacitor. Typical applications are in cellular phone, palmtop/laptop computer, personal digital assistant (PDA), personal stereo, camcorder and camera.
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All features
- Ultra low dropout voltage (0.17 V typ. at 100 mA load, 7 mV typ. at 1 mA load)
- Very low quiescent current (80 μA typ. at no load in on mode; max 1 μA in off mode)
- Guaranteed output current up to 100 mA
- Logic-controlled electronic shutdown
- Output voltage of 2.5; 3.0; 3.3; 5.0 V
- Internal current and thermal limit
- ± 0.75% tolerance output voltage available (A version)
- Output low noise voltage 160 μVRMS
- Temperature range: -40 to 125 °C
- Small package SOT23-5L and SOT-89
- Fast dynamic response to line and load changes
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Related Applications
Industrial
EDA Symbols, Footprints and 3D Models
STMicroelectronics - LD2981
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3D models
Quality and Reliability
Part Number | Marketing Status | Package | Grade | RoHS Compliance Grade | Longevity Commitment | Longevity Starting Date | Material Declaration** |
---|---|---|---|---|---|---|---|
LD2981ABM30TR | Active | SOT23-5L | Industrial | Ecopack2 | - | - | |
LD2981ABM33TR | Active | SOT23-5L | Industrial | Ecopack2 | - | - | |
LD2981ABM50TR | Active | SOT23-5L | Industrial | Ecopack2 | - | - | |
LD2981ABU33TR | Active | SOT-89 | Industrial | Ecopack2 | - | - | |
LD2981ABU50TR | Active | SOT-89 | Industrial | Ecopack2 | - | - | |
LD2981CM30TR | Active | SOT23-5L | Industrial | Ecopack2 | - | - | |
LD2981CM33TR | Active | SOT23-5L | Industrial | Ecopack2 | - | - | |
LD2981CM50TR | Active | SOT23-5L | Industrial | Ecopack2 | - | - | |
LD2981CU33TR | Active | SOT-89 | Industrial | Ecopack2 | - | - | |
LD2981CU50TR | Active | SOT-89 | Industrial | Ecopack2 | - | - |
Marketing Status
Package
SOT23-5L
Grade
Industrial
RoHS Compliance Grade
Ecopack2
Marketing Status
Package
SOT23-5L
Grade
Industrial
RoHS Compliance Grade
Ecopack2
Marketing Status
Package
SOT23-5L
Grade
Industrial
RoHS Compliance Grade
Ecopack2
Marketing Status
Package
SOT-89
Grade
Industrial
RoHS Compliance Grade
Ecopack2
Marketing Status
Package
SOT-89
Grade
Industrial
RoHS Compliance Grade
Ecopack2
Marketing Status
Package
SOT23-5L
Grade
Industrial
RoHS Compliance Grade
Ecopack2
Marketing Status
Package
SOT23-5L
Grade
Industrial
RoHS Compliance Grade
Ecopack2
Marketing Status
Package
SOT23-5L
Grade
Industrial
RoHS Compliance Grade
Ecopack2
Marketing Status
Package
SOT-89
Grade
Industrial
RoHS Compliance Grade
Ecopack2
(**) The Material Declaration forms available on st.com may be generic documents based on the most commonly used package within a package family. For this reason, they may not be 100% accurate for a specific device. Please contact our sales support for information on specific devices.
Sample & Buy
Part Number | Marketing Status | Budgetary Price (US$)*/Qty | Order from ST | Order from distributors | Package | Packing Type | RoHS | Country of Origin | ECCN (US) | ECCN (EU) | Operating temperature (°C) | Operating Temperature (°C) (max) | Grade | Output Voltage (V) (nom) | Output Tolerance (typ) | Output Current (A) (nom) | |||||||||||||||||||||||||||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
min | max | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||
LD2981ABU50TR | | | Available at 3 distributors Distributor availability of LD2981ABU50TR
Distributor reported inventory date: 4/26/2025 | | | | Buy from Distributor | |
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LD2981CM33TR | | | Available at 5 distributors Distributor availability of LD2981CM33TR
Distributor reported inventory date: 4/26/2025 | | | | Buy from Distributor | |
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LD2981ABM50TR | | | Available at 5 distributors Distributor availability of LD2981ABM50TR
Distributor reported inventory date: 4/26/2025 | | | | Buy from Distributor | |
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LD2981CM30TR | | | Available at 3 distributors Distributor availability of LD2981CM30TR
Distributor reported inventory date: 4/26/2025 | | | | Buy from Distributor | |
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LD2981ABU33TR | | | Available at 6 distributors Distributor availability of LD2981ABU33TR
Distributor reported inventory date: 4/26/2025 | | | | Buy from Distributor | |
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LD2981ABM30TR | | | Available at 4 distributors Distributor availability of LD2981ABM30TR
Distributor reported inventory date: 4/26/2025 | | | | Buy from Distributor | |
|
|
|
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LD2981ABM33TR | | | Available at 3 distributors Distributor availability of LD2981ABM33TR
Distributor reported inventory date: 4/26/2025 | | | | Buy from Distributor | |
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LD2981CU50TR | | | Available at 4 distributors Distributor availability of LD2981CU50TR
Distributor reported inventory date: 4/26/2025 | | | | Buy from Distributor | |
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LD2981CM50TR | | | Available at 4 distributors Distributor availability of LD2981CM50TR
Distributor reported inventory date: 4/26/2025 | | | | Buy from Distributor | |
|
|
|
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LD2981CU33TR | | | Available at 3 distributors Distributor availability of LD2981CU33TR
Distributor reported inventory date: 4/26/2025 | | | | Buy from Distributor | |
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LD2981ABU50TR Active
Part Number:
LD2981ABU50TR
Operating Temperature (°C)
Min:
Max:
Grade:
Industrial
Output Voltage (V) (nom):
5
Output Tolerance (typ):
0.75
Output Current (A) (nom):
0.1
Farnell Element14
Stock
6992Min.Order
1MOUSER
Stock
1202Min.Order
1DIGIKEY
Stock
30002Min.Order
1Distributor reported inventory date: 4/26/2025
Stock
Min.Order
LD2981CM33TR Active
Part Number:
LD2981CM33TR
Operating Temperature (°C)
Min:
Max:
Grade:
Industrial
Output Voltage (V) (nom):
3.3
Output Tolerance (typ):
0.75
Output Current (A) (nom):
0.1
MOUSER
Stock
4219Min.Order
1FUTURE
Stock
6000Min.Order
3000AVNET
Stock
33000Min.Order
0DIGIKEY
Stock
10470Min.Order
1Newark Element14
Stock
277Min.Order
0Distributor reported inventory date: 4/26/2025
Stock
Min.Order
LD2981ABM50TR Active
Part Number:
LD2981ABM50TR
Operating Temperature (°C)
Min:
Max:
Grade:
Industrial
Output Voltage (V) (nom):
5
Output Tolerance (typ):
0.75
Output Current (A) (nom):
0.1
Farnell Element14
Stock
1813Min.Order
1MOUSER
Stock
1561Min.Order
1AVNET
Stock
27000Min.Order
0DIGIKEY
Stock
5427Min.Order
1Newark Element14
Stock
1683Min.Order
0Distributor reported inventory date: 4/26/2025
Stock
Min.Order
LD2981CM30TR Active
Part Number:
LD2981CM30TR
Operating Temperature (°C)
Min:
Max:
Grade:
Industrial
Output Voltage (V) (nom):
3
Output Tolerance (typ):
0.75
Output Current (A) (nom):
0.1
Farnell Element14
Stock
1718Min.Order
1MOUSER
Stock
4137Min.Order
1DIGIKEY
Stock
2970Min.Order
1Distributor reported inventory date: 4/26/2025
Stock
Min.Order
LD2981ABU33TR Active
Part Number:
LD2981ABU33TR
Operating Temperature (°C)
Min:
Max:
Grade:
Industrial
Output Voltage (V) (nom):
3.3
Output Tolerance (typ):
0.75
Output Current (A) (nom):
0.1
MOUSER
Stock
4859Min.Order
1FUTURE
Stock
2550Min.Order
1AVNET
Stock
5000Min.Order
0DIGIKEY
Stock
66805Min.Order
1Newark Element14
Stock
2996Min.Order
0YOSUN
Stock
100Min.Order
1Distributor reported inventory date: 4/26/2025
Stock
Min.Order
LD2981ABM30TR Active
Part Number:
LD2981ABM30TR
Operating Temperature (°C)
Min:
Max:
Grade:
Industrial
Output Voltage (V) (nom):
3
Output Tolerance (typ):
0.75
Output Current (A) (nom):
0.1
Farnell Element14
Stock
223Min.Order
1ANGLIA Live
Stock
5Min.Order
1MOUSER
Stock
3126Min.Order
1DIGIKEY
Stock
2978Min.Order
1Distributor reported inventory date: 4/26/2025
Stock
Min.Order
LD2981ABM33TR Active
Part Number:
LD2981ABM33TR
Operating Temperature (°C)
Min:
Max:
Grade:
Industrial
Output Voltage (V) (nom):
3.3
Output Tolerance (typ):
0.75
Output Current (A) (nom):
0.1
Farnell Element14
Stock
1252Min.Order
1MOUSER
Stock
4577Min.Order
1DIGIKEY
Stock
19818Min.Order
1Distributor reported inventory date: 4/26/2025
Stock
Min.Order
LD2981CU50TR Active
Part Number:
LD2981CU50TR
Operating Temperature (°C)
Min:
Max:
Grade:
Industrial
Output Voltage (V) (nom):
5
Output Tolerance (typ):
0.75
Output Current (A) (nom):
0.1
MOUSER
Stock
9624Min.Order
1AVNET
Stock
25000Min.Order
0DIGIKEY
Stock
20389Min.Order
1Newark Element14
Stock
329Min.Order
0Distributor reported inventory date: 4/26/2025
Stock
Min.Order
LD2981CM50TR Active
Part Number:
LD2981CM50TR
Operating Temperature (°C)
Min:
Max:
Grade:
Industrial
Output Voltage (V) (nom):
5
Output Tolerance (typ):
0.75
Output Current (A) (nom):
0.1
Farnell Element14
Stock
619Min.Order
1MOUSER
Stock
4255Min.Order
1AVNET
Stock
15000Min.Order
0DIGIKEY
Stock
13082Min.Order
1Distributor reported inventory date: 4/26/2025
Stock
Min.Order
LD2981CU33TR Active
Part Number:
LD2981CU33TR
Operating Temperature (°C)
Min:
Max:
Grade:
Industrial
Output Voltage (V) (nom):
3.3
Output Tolerance (typ):
0.75
Output Current (A) (nom):
0.1
MOUSER
Stock
8728Min.Order
1DIGIKEY
Stock
2362Min.Order
1Newark Element14
Stock
83Min.Order
0Distributor reported inventory date: 4/26/2025
Stock
Min.Order
(*) Suggested Resale Price (USD) per defined quantity for BUDGETARY USE ONLY. For quotes, prices in local currency, please contact your local ST Sales Office or our Distributors