component
LP3981-28B5F
Public Made by Adomby adom
LOWPOWER Voltage Regulators - Linear, Low Drop Out (LDO) Regulators, SOT-23-5. Pinout cross-checked by two models against the datasheet, KiCad symbol/footprint/3D.
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LP3981-28B5F
LOWPOWER · Voltage Regulators - Linear, Low Drop Out (LDO) Regulators · SOT-23-5
LP3981-28B5F from LOWPOWER, in a SOT-23-5. Pinout and pin descriptions extracted from the manufacturer datasheet (extract_pins, cross-checked by a second model); symbol, footprint, and 3D from KiCad-official CAD.
Pinout
| Pin | Name | Type | Function |
|---|---|---|---|
| 1 | VIN | power_in | Power input voltage pin; the recommended supply input range is 2.5V to 5.5V, and the absolute maximum supply input voltage is 6V. |
| 2 | GND | power_in | Ground reference pin for the LDO regulator, to be returned to a clean analog ground. |
| 3 | EN | input | Chip enable, active high with TTL-logic thresholds (logic-high at 1.2V or above to turn on, logic-low at 0.4V or below to shut down); the pin is high impedance, so a 100kΩ pull-down to GND is recommended when the control signal may float. |
| 4 | NC | unconnected | No connection; this pin is not connected internally. |
| 5 | VOUT | power_out | Regulated output voltage pin; a ceramic output capacitor of at least 1µF with ESR greater than 25mΩ is specified to ensure stability. |
Key specifications
| Parameter | Value |
|---|---|
| Manufacturer | LOWPOWER |
| Package | SOT-23-5 |
| Category | Power Management (PMIC) |
| Pins | 5 |
Electrical characteristics
Limits as printed in the datasheet (page.json metadata.characteristics carries them as data).
| Parameter | Symbol | Min | Typ | Max | Unit | Conditions | Page |
|---|---|---|---|---|---|---|---|
| Output Voltage Accuracy | ΔVOUT | -2 | 2 | % | IOUT = 1mA | 3 | |
| Current Limit | ILIM | 360 | 400 | mA | RLOAD = 1Ω | 3 | |
| Quiescent Current | IQ | 45 | 120 | μA | VEN ≥ 1.2V, IOUT = 0mA | 3 | |
| Dropout Voltage | VDROP | 170 | 200 | mV | IOUT = 200mA, VOUT > 2.8V | 3 | |
| Dropout Voltage | VDROP | 220 | 300 | mV | IOUT = 300mA, VOUT > 2.8V | 3 | |
| Line Regulation | ΔVLINE | 0.3 | % | VIN = (VOUT + 1V) to 5.5V, IOUT = 1mA | 3 | ||
| Load Regulation | ΔVLOAD | 2 | % | 1mA < IOUT < 300mA | 3 | ||
| Standby Current | ISTBY | 0.01 | 1 | μA | VEN = GND, Shutdown | 3 | |
| EN Input Bias Current | IIBSD | 0.01 | 100 | nA | VEN = GND or VIN | 3 | |
| Logic-Low Voltage (EN threshold) | VIL | 0.4 | V | VIN=3V to 5.5V, Shutdown | 3 | ||
| Logic-High Voltage (EN threshold) | VIH | 1.2 | V | VIN=3V to 5.5V, Start-Up | 3 | ||
| Output Noise Voltage | 100 | uVRMS | 10Hz to 100kHz, IOUT=200mA COUT=1µF | 3 | |||
| Maximum Output Current | Imax | 300 | mA | VEN=VIN, VIN>2.5V | 3 | ||
| Supply Input Voltage | 6 | V | 3 | ||||
| Power Dissipation SOT-25 | PD | 400 | mW | TA = 25°C | 3 | ||
| Lead Temperature (Soldering, 10 sec.) | 260 | °C | 10 sec soldering | 3 | |||
| Storage Temperature Range | -65 | 150 | °C | 3 | |||
| ESD Susceptibility HBM | 2 | kV | Human Body Model | 3 | |||
| ESD Susceptibility MM | 200 | V | Machine Model | 3 | |||
| Supply Input Voltage | 2.5 | 5.5 | V | 3 | |||
| EN Input Voltage | 0 | 5.5 | V | 3 | |||
| Operation Junction Temperature Range | -40 | 125 | °C | 3 | |||
| Operation Ambient Temperature Range | -40 | 85 | °C | 3 | |||
| Package Thermal Resistance SOT-25 | θJA | 250 | °C/W | 3 | |||
| Power Supply Rejection Rate | PSRR | -76 | dB | f=100Hz, COUT=1µF, IOUT=50mA | 3 | ||
| Power Supply Rejection Rate | PSRR | -73 | dB | f=10kHz, COUT=1µF, IOUT=50mA | 3 | ||
| Thermal Shutdown Temperature | TSD | 150 | °C | 3 |
CAD (KiCad official)
- Symbol:
LP3981-28B5F - Footprint:
Package_TO_SOT_SMD:SOT-23-5 - 3D model: SOT-23-5 (KiCad packages3D, STEP)
- 3D model files:
lp3981-28b5f-etched.step/lp3981-28b5f-etched.glbcarry the MPN laser-etched on the die in a toggleableAdom.LaserEtchgroup (Fusion-ready);lp3981-28b5f.step/lp3981-28b5f.glbare the bare package body.
Provenance
Data extracted from the manufacturer datasheet, not a distributor listing:
- Datasheet: LOWPOWER datasheet (6 pp, sha256
bf3050f50c362057, retrieved 2026-10-18, tier: lcsc) - Extractor: parts-factory
2.0.0/extract_pins 0.3, primaryclaude-haiku-5-5(text), consensusclaude-sonnet-5-5(agreed), guards: pin_guards 0.1: passed. Pins are checked against the footprint pad set and their cited datasheet pages before publish. - CAD: KiCad official libraries (CC-BY-SA 4.0).
# LP3981-28B5F
**LOWPOWER** · Voltage Regulators - Linear, Low Drop Out (LDO) Regulators · SOT-23-5
LP3981-28B5F from LOWPOWER, in a SOT-23-5. Pinout and pin descriptions extracted from the manufacturer datasheet (extract_pins, cross-checked by a second model); symbol, footprint, and 3D from KiCad-official CAD.
## Pinout
| Pin | Name | Type | Function |
|---|---|---|---|
| 1 | VIN | power_in | Power input voltage pin; the recommended supply input range is 2.5V to 5.5V, and the absolute maximum supply input voltage is 6V. |
| 2 | GND | power_in | Ground reference pin for the LDO regulator, to be returned to a clean analog ground. |
| 3 | EN | input | Chip enable, active high with TTL-logic thresholds (logic-high at 1.2V or above to turn on, logic-low at 0.4V or below to shut down); the pin is high impedance, so a 100kΩ pull-down to GND is recommended when the control signal may float. |
| 4 | NC | unconnected | No connection; this pin is not connected internally. |
| 5 | VOUT | power_out | Regulated output voltage pin; a ceramic output capacitor of at least 1µF with ESR greater than 25mΩ is specified to ensure stability. |
## Key specifications
| Parameter | Value |
|---|---|
| Manufacturer | LOWPOWER |
| Package | SOT-23-5 |
| Category | Power Management (PMIC) |
| Pins | 5 |
## Electrical characteristics
Limits as printed in the datasheet (page.json `metadata.characteristics` carries them as data).
| Parameter | Symbol | Min | Typ | Max | Unit | Conditions | Page |
|---|---|---|---|---|---|---|---|
| Output Voltage Accuracy | ΔVOUT | -2 | | 2 | % | IOUT = 1mA | 3 |
| Current Limit | ILIM | | 360 | 400 | mA | RLOAD = 1Ω | 3 |
| Quiescent Current | IQ | | 45 | 120 | μA | VEN ≥ 1.2V, IOUT = 0mA | 3 |
| Dropout Voltage | VDROP | | 170 | 200 | mV | IOUT = 200mA, VOUT > 2.8V | 3 |
| Dropout Voltage | VDROP | | 220 | 300 | mV | IOUT = 300mA, VOUT > 2.8V | 3 |
| Line Regulation | ΔVLINE | | | 0.3 | % | VIN = (VOUT + 1V) to 5.5V, IOUT = 1mA | 3 |
| Load Regulation | ΔVLOAD | | | 2 | % | 1mA < IOUT < 300mA | 3 |
| Standby Current | ISTBY | | 0.01 | 1 | μA | VEN = GND, Shutdown | 3 |
| EN Input Bias Current | IIBSD | | 0.01 | 100 | nA | VEN = GND or VIN | 3 |
| Logic-Low Voltage (EN threshold) | VIL | | | 0.4 | V | VIN=3V to 5.5V, Shutdown | 3 |
| Logic-High Voltage (EN threshold) | VIH | 1.2 | | | V | VIN=3V to 5.5V, Start-Up | 3 |
| Output Noise Voltage | | | | 100 | uVRMS | 10Hz to 100kHz, IOUT=200mA COUT=1µF | 3 |
| Maximum Output Current | Imax | | | 300 | mA | VEN=VIN, VIN>2.5V | 3 |
| Supply Input Voltage | | | | 6 | V | | 3 |
| Power Dissipation SOT-25 | PD | | | 400 | mW | TA = 25°C | 3 |
| Lead Temperature (Soldering, 10 sec.) | | | | 260 | °C | 10 sec soldering | 3 |
| Storage Temperature Range | | -65 | | 150 | °C | | 3 |
| ESD Susceptibility HBM | | | | 2 | kV | Human Body Model | 3 |
| ESD Susceptibility MM | | | | 200 | V | Machine Model | 3 |
| Supply Input Voltage | | 2.5 | | 5.5 | V | | 3 |
| EN Input Voltage | | 0 | | 5.5 | V | | 3 |
| Operation Junction Temperature Range | | -40 | | 125 | °C | | 3 |
| Operation Ambient Temperature Range | | -40 | | 85 | °C | | 3 |
| Package Thermal Resistance SOT-25 | θJA | | 250 | | °C/W | | 3 |
| Power Supply Rejection Rate | PSRR | | -76 | | dB | f=100Hz, COUT=1µF, IOUT=50mA | 3 |
| Power Supply Rejection Rate | PSRR | | -73 | | dB | f=10kHz, COUT=1µF, IOUT=50mA | 3 |
| Thermal Shutdown Temperature | TSD | | 150 | | °C | | 3 |
## CAD (KiCad official)
- Symbol: `LP3981-28B5F`
- Footprint: `Package_TO_SOT_SMD:SOT-23-5`
- 3D model: SOT-23-5 (KiCad packages3D, STEP)
- 3D model files: `lp3981-28b5f-etched.step` / `lp3981-28b5f-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `lp3981-28b5f.step` / `lp3981-28b5f.glb` are the bare package body.
## Provenance
Data extracted from the manufacturer datasheet, not a distributor listing:
- **Datasheet:** [LOWPOWER datasheet](https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8588912711329177600) (6 pp, sha256 `bf3050f50c362057`, retrieved 2026-10-18, tier: lcsc)
- **Extractor:** parts-factory `2.0.0` / `extract_pins 0.3`, primary `claude-haiku-5-5` (text), consensus `claude-sonnet-5-5` (agreed), guards: pin_guards 0.1: passed. Pins are checked against the footprint pad set and their cited datasheet pages before publish.
- **CAD:** KiCad official libraries (CC-BY-SA 4.0).
[Datasheet PDF](docs/lp3981-28b5f-datasheet.pdf)