Product overview
Description
The LD3985 provides up to 150 mA, from 2.5 V to 6 V input voltage. The ultra low drop voltage, low quiescent current and low noise make it suitable for low power applications and in battery-powered systems. Regulator ground current increases slightly in dropout only, prolonging the battery life. Power supply rejection is better than 60 dB at low frequencies and rolls off at 10 kHz. High power supply rejection is maintained down to low input voltage levels common to battery operated circuits. Shutdown logic control function is available, 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 LD3985 is designed to work with low ESR ceramic capacitors. Typical applications are in mobile phones and similar battery-powered wireless systems.
-
All features
- Input voltage from 2.5 to 6 V
- Stable with low ESR ceramic capacitors
- Ultra low-dropout voltage (60 mV typ. at 150 mA load, 0.4 mV typ. at1 mA load)
- Very low quiescent current (85 μA typ. at no load, 170 μA typ. at 150 mA load; max.1.5 μA in OFF mode)
- Guaranteed output current up to 150 mA
- Wide range of output voltages: 1.22 V; 1.8 V; 2.5 V; 2.7 V; 2.8 V;2.9 V; 3.3 V; 4.7 V
- Fast turn-on time: typ. 200 μs [CO = 1 μF, CBYP = 10 nF and IO = 1 mA]
- Logic-controlled electronic shutdown
- Internal current and thermal limit
- Output low noise voltage 30 μVRMS over 10 Hz to 100 kHz
- SVR of 60 dB at 1 kHz, 50 dB at 10 kHz
- Temperature range: -40 °C to 125 °C
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Related Applications
All resources
| Resource title | Version | Latest update |
|---|
Product Specifications (1)
| Resource title | Version | Latest update | ||
|---|---|---|---|---|
| 17.0 | 06 Dec 2019 | 06 Dec 2019 |
Presentations (1)
| Resource title | Version | Latest update | ||
|---|---|---|---|---|
| 2.2 | 02 Aug 2023 | 02 Aug 2023 |
Flyers (2)
| Resource title | Version | Latest update | ||
|---|---|---|---|---|
| 1.0 | 19 Sep 2023 | 19 Sep 2023 | ||
| 1.0 | 05 Jul 2024 | 05 Jul 2024 |
Brochures (3)
| Resource title | Version | Latest update | ||
|---|---|---|---|---|
| 3.0 | 27 Jul 2022 | 27 Jul 2022 | ||
| 2.0 | 17 Jul 2024 | 17 Jul 2024 | ||
| 2.0 | 25 May 2023 | 25 May 2023 |
EDA Symbols, Footprints and 3D Models
STMicroelectronics - LD3985
Speed up your design by downloading all the EDA symbols, footprints and 3D models for your application. You have access to a large number of CAD formats to fit with your design toolchain.
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Symbols
Footprints
3D models
Quality and Reliability
| Part Number | Marketing Status | Package | Grade | RoHS Compliance Grade | Material Declaration** |
|---|---|---|---|---|---|
| LD3985M122R | Active | SOT23-5L | Industrial | Ecopack2 | |
| LD3985M18R | Active | SOT23-5L | Industrial | Ecopack2 | |
| LD3985M25R | Active | SOT23-5L | Industrial | Ecopack2 | |
| LD3985M27R | Active | SOT23-5L | Industrial | Ecopack2 | |
| LD3985M28R | Active | SOT23-5L | Industrial | Ecopack2 | |
| LD3985M29R | Active | SOT23-5L | Industrial | Ecopack2 | |
| LD3985M30R | Active | SOT23-5L | Industrial | Ecopack2 | |
| LD3985M33R | Active | SOT23-5L | Industrial | Ecopack3 | |
| LD3985M47R | Active | SOT23-5L | 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
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
SOT23-5L
Grade
Industrial
RoHS Compliance Grade
Ecopack2
Marketing Status
Package
SOT23-5L
Grade
Industrial
RoHS Compliance Grade
Ecopack3
Marketing Status
Package
SOT23-5L
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 | ||||||||||||||||||||||||||||||||||||||||||||||
| LD3985M47R | Active | 0.2788 / 1k | Available at 2 distributors Distributor availability of LD3985M47R
Distributor reported inventory date: 3/29/2025 | | | | Buy from Distributor | | SOT23-5L | Tape and Reel | MALAYSIA | EAR99 | NEC | -40 | 125 | Industrial | 4.7 | 2 | 0.15 | ||||||||||||||||||||||||||||
| LD3985M25R | Active | 0.2788 / 1k | Available at 2 distributors Distributor availability of LD3985M25R
Distributor reported inventory date: 3/29/2025 | | | | Buy from Distributor | | SOT23-5L | Tape and Reel | CHINA | EAR99 | NEC | -40 | 125 | Industrial | 2.5 | 2 | 0.15 | ||||||||||||||||||||||||||||
| LD3985M33R | Active | 0.2788 / 1k | Available at 3 distributors Distributor availability of LD3985M33R
Distributor reported inventory date: 3/29/2025 | | | | Buy from Distributor | | SOT23-5L | Tape and Reel | CHINA | EAR99 | NEC | -40 | 125 | Industrial | 3.3 | 2 | 0.15 | ||||||||||||||||||||||||||||
| LD3985M122R | Active | 0.2788 / 1k | Available at 1 distributors Distributor availability of LD3985M122R
Distributor reported inventory date: 3/29/2025 | | | | Buy from Distributor | | SOT23-5L | Tape and Reel | MALAYSIA | EAR99 | NEC | -40 | 125 | Industrial | 1.22 | 2 | 0.15 | ||||||||||||||||||||||||||||
| LD3985M18R | Active | 0.2788 / 1k | Available at 3 distributors Distributor availability of LD3985M18R
Distributor reported inventory date: 3/29/2025 | | | | Buy from Distributor | | SOT23-5L | Tape and Reel | MALAYSIA | EAR99 | NEC | -40 | 125 | Industrial | 1.8 | 2 | 0.15 | ||||||||||||||||||||||||||||
| LD3985M30R | Active | 0.2788 / 1k | Available at 4 distributors Distributor availability of LD3985M30R
Distributor reported inventory date: 3/29/2025 | | | | Buy from Distributor | | SOT23-5L | Tape and Reel | CHINA | EAR99 | NEC | -40 | 125 | Industrial | 3 | 2 | 0.15 | ||||||||||||||||||||||||||||
| LD3985M27R | Active | 0.2788 / 1k | Available at 2 distributors Distributor availability of LD3985M27R
Distributor reported inventory date: 3/29/2025 | | | | Buy from Distributor | | SOT23-5L | Tape and Reel | MALAYSIA | EAR99 | NEC | -40 | 125 | Industrial | 2.7 | 2 | 0.15 | ||||||||||||||||||||||||||||
| LD3985M29R | Active | 0.2788 / 1k | Available at distributors Distributor availability of LD3985M29R
Distributor reported inventory date: | | | | Buy from Distributor | | SOT23-5L | Tape and Reel | MALAYSIA | EAR99 | NEC | -40 | 125 | Industrial | 2.9 | 2 | 0.15 | ||||||||||||||||||||||||||||
| LD3985M28R | Active | 0.2788 / 1k | Available at 2 distributors Distributor availability of LD3985M28R
Distributor reported inventory date: 3/29/2025 | | | | Buy from Distributor | | SOT23-5L | Tape and Reel | MALAYSIA | EAR99 | NEC | -40 | 125 | Industrial | 2.8 | 2 | 0.15 | ||||||||||||||||||||||||||||
LD3985M47R Active
Part Number:
LD3985M47R
Operating Temperature (°C)
Min:
-40
Max:
125
Grade:
Industrial
Output Voltage (V) (nom):
4.7
Output Tolerance (typ):
2
Output Current (A) (nom):
0.15
MOUSER
Stock
8Min.Order
1DIGIKEY
Stock
11Min.Order
1Distributor reported inventory date: 3/29/2025
Stock
Min.Order
LD3985M25R Active
Part Number:
LD3985M25R
Operating Temperature (°C)
Min:
-40
Max:
125
Grade:
Industrial
Output Voltage (V) (nom):
2.5
Output Tolerance (typ):
2
Output Current (A) (nom):
0.15
MOUSER
Stock
4606Min.Order
1DIGIKEY
Stock
8487Min.Order
1Distributor reported inventory date: 3/29/2025
Stock
Min.Order
LD3985M33R Active
Part Number:
LD3985M33R
Operating Temperature (°C)
Min:
-40
Max:
125
Grade:
Industrial
Output Voltage (V) (nom):
3.3
Output Tolerance (typ):
2
Output Current (A) (nom):
0.15
Farnell Element14
Stock
20731Min.Order
1MOUSER
Stock
60061Min.Order
1DIGIKEY
Stock
28798Min.Order
1Distributor reported inventory date: 3/29/2025
Stock
Min.Order
LD3985M122R Active
Part Number:
LD3985M122R
Operating Temperature (°C)
Min:
-40
Max:
125
Grade:
Industrial
Output Voltage (V) (nom):
1.22
Output Tolerance (typ):
2
Output Current (A) (nom):
0.15
DIGIKEY
Stock
422Min.Order
1Distributor reported inventory date: 3/29/2025
Stock
Min.Order
LD3985M18R Active
Part Number:
LD3985M18R
Operating Temperature (°C)
Min:
-40
Max:
125
Grade:
Industrial
Output Voltage (V) (nom):
1.8
Output Tolerance (typ):
2
Output Current (A) (nom):
0.15
MOUSER
Stock
3266Min.Order
1FUTURE
Stock
3000Min.Order
3000DIGIKEY
Stock
18707Min.Order
1Distributor reported inventory date: 3/29/2025
Stock
Min.Order
LD3985M30R Active
Part Number:
LD3985M30R
Operating Temperature (°C)
Min:
-40
Max:
125
Grade:
Industrial
Output Voltage (V) (nom):
3
Output Tolerance (typ):
2
Output Current (A) (nom):
0.15
Farnell Element14
Stock
3273Min.Order
1MOUSER
Stock
9847Min.Order
1AVNET
Stock
54000Min.Order
0DIGIKEY
Stock
25252Min.Order
1Distributor reported inventory date: 3/29/2025
Stock
Min.Order
LD3985M27R Active
Part Number:
LD3985M27R
Operating Temperature (°C)
Min:
-40
Max:
125
Grade:
Industrial
Output Voltage (V) (nom):
2.7
Output Tolerance (typ):
2
Output Current (A) (nom):
0.15
MOUSER
Stock
8561Min.Order
1DIGIKEY
Stock
2863Min.Order
1Distributor reported inventory date: 3/29/2025
Stock
Min.Order
LD3985M29R Active
Part Number:
LD3985M29R
Operating Temperature (°C)
Min:
-40
Max:
125
Grade:
Industrial
Output Voltage (V) (nom):
2.9
Output Tolerance (typ):
2
Output Current (A) (nom):
0.15
Distributor reported inventory date:
Stock
Min.Order
LD3985M28R Active
Part Number:
LD3985M28R
Operating Temperature (°C)
Min:
-40
Max:
125
Grade:
Industrial
Output Voltage (V) (nom):
2.8
Output Tolerance (typ):
2
Output Current (A) (nom):
0.15
Farnell Element14
Stock
1598Min.Order
1MOUSER
Stock
2532Min.Order
1Distributor reported inventory date: 3/29/2025
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