NJW4181U3-15B - 100mA 35V LDO Regulator, 1.5V Fixed | Nisshinbo
Teilenummer: NJW4181U3-15B ✓ Aktiv| Menge | Stückpreis | Gesamt |
|---|---|---|
| 1 | $1.25 | $1,25 |
| 10 | $1.1 | $11,00 |
| 100 | $0.95 | $95,00 |
| 500 | $0.82 | $410,00 |
| 1.000 | $0.7 | $700,00 |
NJW4181U3-15B Übersicht
An LDO (Low-Dropout) linear regulator is a DC voltage regulator that maintains a stable output voltage even when the input-to-output differential is small. As a member of the linear regulator family within the broader voltage-regulator and power-management-IC hierarchy, an LDO uses a pass element (typically a PNP transistor or P-channel MOSFET) that is never fully saturated, trading efficiency for low noise and fast transient response. LDOs are preferred over switching regulators in noise-sensitive analog and sensor signal chains because they introduce no switching ripple.
Key features of the NJW4181U3-15B include 100 mA continuous output current, 1.5 V fixed output (factory-trimmed, no external resistors required), 9 µA typical quiescent current to minimize standby drain on battery-backed systems, and an input range that comfortably covers 24 V industrial rails. The part is offered in two packages: the 3-pin SOT-89 (U3) for direct 78L-series replacement, and the smaller ESON6 DFN for space-constrained sensor modules. Per the manufacturer datasheet, the device integrates internal current limit and thermal shutdown protection.
Architecturally, the NJW4181U3-15B uses a PNP pass element with a precision bandgap reference and error amplifier, achieving the very-low-Iq target by biasing internal nodes with low-current mirrors. The wide VIN tolerance is enabled by the high-VCEO PNP process used at Nisshinbo's bipolar fab, allowing safe operation up to 35 V without external protection. Compared with classic 78L05/78L12 parts, the NJW4181 family lowers quiescent current by roughly an order of magnitude while keeping the same 3-terminal pinout.
Typical applications include 24 V industrial sensor power conditioning, battery-powered IoT endpoints, microcontroller always-on rails, metering and HVAC peripherals, and any subsystem requiring post-regulation after a 24 V to 30 V bus. The fixed 1.5 V output is a common core voltage for low-power digital signal chains and legacy logic families.
When designing with this part, ensure that input-to-output headroom stays within the dropout limit at the required load, and provide adequate copper area under the SOT-89 tab for thermal dissipation. For battery applications, the 9 µA Iq becomes the dominant standby draw and should be included in the energy budget.
This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet alone.
Drop-in-Alternativen für NJW4181U3-15B – gleiches Gehäuse, Pin-kompatibel. Bauteile mit anderem Gehäuse, die eine PCB-Überarbeitung erfordern, sind ausgeschlossen.
Schnellvergleichstool – Wählen Sie Alternativbauteile für den Direktvergleich:
NJW4181U3-33
✅ Drop-In ⚠️ Spezifikationen ungeprüft📋 Referenzalternative (nicht im Katalog)
NJW4181U3-05
✅ Drop-In ⚠️ Spezifikationen ungeprüft📋 Referenzalternative (nicht im Katalog)
NJW4181U3-12
✅ Drop-In ⚠️ Spezifikationen ungeprüft📋 Referenzalternative (nicht im Katalog)
NJW4181U3-25
✅ Drop-In ⚠️ Spezifikationen ungeprüft📋 Referenzalternative (nicht im Katalog)
NJW4181U2-15B
✅ Drop-In ⚠️ Spezifikationen ungeprüft📋 Referenzalternative (nicht im Katalog)
NJW4181U3-15B Grenzwerte & elektrische Eigenschaften
| Manufacturer | Nisshinbo Micro Devices Inc. |
| Series | NJW4181 |
| Regulator Type | LDO, Fixed, Positive |
| Output Voltage (Nominal) | 1.5 V |
| Maximaler Ausgangsstrom | 100 mA |
| Eingangsspannungsbereich | 17 V to 35 V |
| Quiescent Current (Typical) | 9 µA |
| Betriebstemperaturbereich | -40 °C to +125 °C |
| Thermisches Abschalten | Internal |
| Strombegrenzung | Internal |
| Gehäuse | SOT-89 (U3), 3 pins |
| Montageart | Surface Mount |
| RoHS-Status | Compliant |
| Lead-Free | Yes |
| Country of Origin | Japan |
NJW4181U3-15B Pin-Konfiguration
| Pin 1 | VIN — Input voltage (17V to 35V) |
| Pin 2 | GND — Ground |
| Pin 3 | VOUT — Regulated 1.5V output |
Typische Anwendungen
NJW4181U3-15B ist geeignet für 6 Anwendungs: 24V Industrial Sensor Power Conditioning, Battery-Powered IoT Endpoint, 24V Bus Post-Regulator for Microcontroller Rails, HVAC and Building Automation Peripherals, Automotive 12V/24V Sensor Power Rail, Metering and Measurement Front-End.
24V Industrial Sensor Power Conditioning
The NJW4181U3-15B fits 24 V industrial sensor power conditioning because its 17 V to 35 V input range directly accepts a nominal 24 V rail with ample headroom for transients and load-dump events typical of factory automation environments. The 100 mA output capability is well matched to low-power sensor signal chains, 1.5 V ADC references, and microcontroller always-on rails. Compared to a switching regulator, the linear LDO adds no switching noise — important for precision analog sensors — and the 9 µA quiescent current keeps standby drain low in battery-backed field instrumentation. Place a 1 µF ceramic input capacitor and a 1 µF to 10 µF output capacitor close to the device, and provide at least 50 mm² of copper under the SOT-89 tab to keep junction temperature within the -40 °C to +125 °C range at full load.
Empfohlen
Battery-Powered IoT Endpoint
The NJW4181U3-15B suits battery-powered IoT endpoints because its 9 µA quiescent current becomes a near-negligible share of the total system energy budget, especially when the MCU is in deep sleep. The fixed 1.5 V output can power low-power wireless transceivers, MEMS sensor front-ends, or RTC domains that need a stable always-on rail. The wide 17 V to 35 V input allows direct connection to a multi-cell battery stack or a high-voltage harvesting source (e.g., solar or thermoelectric). The SOT-89 (U3) package provides adequate thermal dissipation for 100 mA bursts during active transmission without requiring an external heatsink, while the very-low-Iq design extends battery life by 5x to 10x compared with legacy 78L-series parts.
Empfohlen
24V Bus Post-Regulator for Microcontroller Rails
The NJW4181U3-15B works as a 24 V bus post-regulator for microcontroller core and I/O rails because its 35 V input tolerance easily survives inductive switching transients on industrial field wiring. The fixed 1.5 V output is well suited to legacy 1.5 V logic families and as a reference for ADC inputs in mixed-voltage systems. With 100 mA available, the part can power a small MCU plus its associated analog front-end from a single 24 V bus without an intermediate switching converter, simplifying the BOM and EMI signature. Use a 10 µF ceramic output capacitor to maintain stability under load transients, and add a TVS diode at the input if the bus is exposed to outdoor surge events.
Empfohlen
HVAC and Building Automation Peripherals
The NJW4181U3-15B fits HVAC and building automation peripherals because the 24 VAC rectified supply commonly used in thermostats and damper actuators falls squarely within its 17 V to 35 V input range. The 100 mA output is sufficient for sensor signal conditioning, low-power MCUs, and 1.5 V reference rails. The very-low 9 µA quiescent current is a key advantage in battery-backed smoke detectors and wireless thermostats where standby lifetime is critical. The SOT-89 package handles the -40 °C to +125 °C industrial temperature range without thermal derating at typical 10-50 mA loads, and the linear topology introduces no EMI that could interfere with RF links in wireless thermostats.
Empfohlen
Automotive 12V/24V Sensor Power Rail
Although the NJW4181U3-15B is not AEC-Q100 qualified, the part is widely used in non-safety automotive applications such as cabin accessories, infotainment peripherals, and aftermarket sensor modules where the 17 V to 35 V input range easily handles 12 V cranking transients and 24 V truck bus voltages. The fixed 1.5 V output is useful for powering low-voltage digital isolators, signal-conditioning ICs, and sensor analog front-ends. The linear LDO topology avoids the EMI of switching converters that could couple into AM/FM antennas or CAN bus lines. For under-the-hood or safety-critical applications, select an AEC-Q100-qualified alternative instead.
Empfohlen
Metering and Measurement Front-End
The NJW4181U3-15B suits metering and measurement front-ends because its linear topology adds no switching ripple that could couple into sensitive analog measurement channels. The 1.5 V output is a common reference voltage for 16-bit and 24-bit ADCs used in electricity, water, and gas meters. The 100 mA output capability is adequate to power the ADC, an MCU, and a low-power LCD or LED display. The wide 17 V to 35 V input range supports direct connection to rectified mains-derived rails in isolated power supplies, and the 9 µA quiescent current is negligible compared to the typical 10-50 mA active consumption of the meter's measurement and communication circuits.
Empfohlen
Zusammenfassung der empfohlenen Produkte
Technische Referenzdaten für NJW4181U3-15B – Vergleich, Designhinweise und Compliance-Informationen.
Auswahlhilfe
Vergleich mit Alternativen
| Parameter | Dieses Produkt | NJW4181U3-33 | NJW4181U3-05 | NJW4181U3-12 | NJW4181U3-25 | NJW4181U2-15B |
|---|---|---|---|---|---|---|
| Package | SOT-89 (U3) | SOT-89 (U3) - same | SOT-89 (U3) - same | SOT-89 (U3) - same | SOT-89 (U3) - same | SOT-89 (U3) - same |
| Brand | Nisshinbo Micro Devices | Nisshinbo Micro Devices | Nisshinbo Micro Devices | Nisshinbo Micro Devices | Nisshinbo Micro Devices | Nisshinbo Micro Devices |
| Output Voltage | 1.5 V | 3.3 V | 5.0 V | 12 V | 2.5 V | 1.5 V |
| Output Current | 100 mA | 100 mA | 100 mA | 100 mA | 100 mA | 100 mA |
| Quiescent Current | 9 µA | 9 µA | 9 µA | 9 µA | 9 µA | 9 µA |
| Regulator Type | LDO Fixed Positive | LDO Fixed Positive | LDO Fixed Positive | LDO Fixed Positive | LDO Fixed Positive | LDO Fixed Positive |
| Operating Temperature | -40 °C to +125 °C | -40 °C to +125 °C | -40 °C to +125 °C | -40 °C to +125 °C | -40 °C to +125 °C | -40 °C to +125 °C |
Wichtigste Unterscheidungsmerkmale
- Very-low 9 µA quiescent current vs 1-3 mA for legacy 78L-series (vs. 78L15 (legacy 3-terminal regulator))
- Wide 17 V to 35 V input range directly accepts 24 V industrial rails (vs. NJW4181U3-33 (same family, 3.3V output))
- Same NJW4181 family supports SOT-89 and ESON6 DFN packages (vs. 78L15 in TO-92 or SOT-89)
Designhinweise
Estimated: at VIN=24V, VOUT=1.5V, IOUT=100mA, the NJW4181U3-15B dissipates approximately 2.25W. With the SOT-89 (U3) package thermal resistance of approximately 100 °C/W on a standard JEDEC 1oz 4-layer test board, the junction temperature rise above ambient is roughly 225 °C at full load — clearly above the 150 °C absolute maximum. Therefore, at full 100 mA load and 24 V input, a continuous operation requires either a substantial copper heatsink (1+ cm²) on the tab or operation at a lower VIN. The datasheet thermal curves should be consulted before finalizing the layout.
Per Nisshinbo’s recommended land pattern, place the input capacitor (1 µF X7R ceramic minimum, 10 µF preferred) as close as possible to the VIN pin and the output capacitor (1 µF to 10 µF X7R ceramic) as close as possible to the VOUT pin. The SOT-89 tab (pin 2 on most variants, or floating tab) should be soldered to a copper pour that is thermally connected to VIN or GND depending on the variant. Use 1 oz copper or thicker on outer layers to maximize heat spreading under the package.
Do not exceed the absolute maximum input voltage of 35 V (or higher transient as specified in the datasheet). The NJW4181U3-15B is a 3-terminal device with no enable pin, so adding a power-switching MOSFET upstream is required if the application needs to cut quiescent current to zero. The 9 µA Iq is the dominant standby drain — verify that the upstream supply can be switched off if the system must achieve true zero-Iq standby. Reverse-voltage protection at the input is recommended if the source can be connected backwards.
Compliance-Informationen
RoHS compliant per Nisshinbo product page. Not AEC-Q100 qualified. Lead-free SOT-89 package.
