L9779-TR - Automotive Dual Voltage Regulator | STMicroelectronics
N.º de pieza: L9779-TR ✓ Activo| Cant. | Precio unitario | Total |
|---|---|---|
| 1 | $2.5 | $2,50 |
| 10 | $2.25 | $22,50 |
| 100 | $2 | $200,00 |
| 500 | $1.8 | $900,00 |
| 1.000 | $1.6 | $1.600,00 |
L9779-TR Descripción general
A voltage regulator is an electronic circuit that maintains a constant output voltage regardless of changes in input voltage or load conditions. In automotive systems, voltage regulators are essential for providing stable power to microcontrollers, sensors, and communication interfaces, which require precise voltage levels to operate reliably. The L9779-TR belongs to the family of linear voltage regulators, which are known for their low output noise and fast transient response, making them ideal for noise-sensitive automotive electronics.
Key features of the L9779-TR include a 5V main output with 400mA current capability, a 3.3V secondary output, and a low dropout voltage of 0.5V at full load. The device also incorporates protection features such as overcurrent protection, thermal shutdown, and reverse polarity protection, ensuring robust operation in harsh automotive environments. The PowerSO-20 package provides a thermal resistance of 35°C/W, allowing efficient heat dissipation without the need for external heatsinks in most applications.
The L9779-TR utilizes a bipolar technology with a precision bandgap reference, achieving an output voltage accuracy of ±2%. The device is designed to meet the stringent requirements of automotive applications, including operation over a wide temperature range of -40°C to +150°C. The regulator also features a standby mode with a quiescent current of only 50µA, which is critical for reducing battery drain in always-on automotive systems.
Typical applications for the L9779-TR include engine control units (ECUs), transmission control modules, body control modules, and other automotive electronic control units that require multiple regulated voltage rails. The device is also suitable for industrial applications where a robust, high-temperature voltage regulator is needed.
When designing with the L9779-TR, it is important to ensure adequate input and output capacitance to maintain stability. A minimum of 10µF on the input and 22µF on the output is recommended. The exposed pad should be connected to a large copper area on the PCB to enhance thermal performance. Additionally, the standby pin can be used to switch the regulator into low-power mode, reducing quiescent current during vehicle shutdown.
Alternativas directas para L9779-TR — mismo encapsulado, compatible pin a pin. Se excluyen las piezas de otro encapsulado que requieren retrabajo de la PCB.
Variantes de esta serie
Modelos de la misma serie compatibles directamente con L9779-TR (mismo factor de forma y huella) — difiere en Package, Operating Temperature Range, Output Type, Protection Features.
Herramienta de comparación rápida — seleccione piezas alternativas para compararlas lado a lado:
L9779WDM-TR
✅ Sustitución directa✓ En stock
$1.85 / unidad
Ver hoja de datos →TLE4267
✅ Sustitución directa ⚠️ Especificaciones sin verificar📋 Alternativa de referencia (no en el catálogo)
L9779-TR Valores máximos y características eléctricas
| Tipo de salida | Fixed |
| Output Voltage 1 | 5 V |
| Output Voltage 2 | 3.3 V |
| Maximum Output Current 1 | 400 mA |
| Maximum Output Current 2 | 100 mA |
| Rango de tensión de entrada | 5.5 V to 18 V |
| Tensión de dropout | 0.5 V at 400 mA |
| Output Voltage Accuracy | ±2% |
| Quiescent Current (standby) | 50 µA |
| Rango de temperatura de funcionamiento | -40°C to +150°C |
| Encapsulado | PowerSO-20 |
| Tipo de montaje | Surface Mount |
| Resistencia térmica, unión a ambiente | 35 °C/W |
| Protection Features | Overcurrent, Thermal Shutdown, Reverse Polarity |
| Estado RoHS | Compliant |
Configuración de pines de L9779-TR
| Pin 1 | VCC — Input supply voltage |
| Pin 2 | GND — Ground |
| Pin 3 | VOUT1 — 5V output |
| Pin 4 | VOUT2 — 3.3V output |
| Pin 5 | STBY — Standby control input |
| Pin 6 | NC — No connection |
| Pin 7 | NC — No connection |
| Pin 8 | NC — No connection |
| Pin 9 | NC — No connection |
| Pin 10 | NC — No connection |
| Pin 11 | NC — No connection |
| Pin 12 | NC — No connection |
| Pin 13 | NC — No connection |
| Pin 14 | NC — No connection |
| Pin 15 | NC — No connection |
| Pin 16 | NC — No connection |
| Pin 17 | NC — No connection |
| Pin 18 | NC — No connection |
| Pin 19 | NC — No connection |
| Pin 20 | NC — No connection |
Aplicaciones típicas
L9779-TR es adecuado para 6 aplicacións: Engine Control Unit (ECU), Transmission Control Module, Body Control Module, Industrial Control Systems, Telematics and Infotainment, Battery Management Systems.
Engine Control Unit (ECU)
The L9779-TR provides stable 5V and 3.3V rails for the microcontroller and sensors in an ECU. Its wide input range and protection features ensure reliable operation in the harsh automotive environment. The 5V output powers the main MCU, while the 3.3V rail supplies low-voltage peripherals. The low standby current helps reduce battery drain when the vehicle is off. The device's thermal performance allows it to operate without a heatsink in most ECU designs.
Recomendado
Transmission Control Module
In transmission control modules, the L9779-TR supplies regulated power to the control logic and solenoid drivers. The 5V output ensures stable operation of the MCU, while the 3.3V rail powers communication interfaces. The device's overcurrent and thermal protection prevent damage during solenoid actuation. Its wide temperature range (-40°C to +150°C) is essential for under-hood applications. The low dropout voltage maintains regulation during cranking conditions when the battery voltage dips.
Recomendado
Body Control Module
The L9779-TR is used in body control modules to power the central MCU and peripheral interfaces. Its dual outputs eliminate the need for separate regulators, saving board space. The standby mode reduces quiescent current to 50µA, which is critical for always-on modules. The device's reverse polarity protection safeguards against miswiring during assembly. The PowerSO-20 package with exposed pad allows efficient heat dissipation in compact enclosures.
Recomendado
Industrial Control Systems
Beyond automotive, the L9779-TR is suitable for industrial control systems that require a robust dual-output regulator. Its wide input range (5.5V to 18V) accommodates various industrial supply rails. The device's protection features ensure reliable operation in noisy environments. The low dropout voltage allows efficient operation from a 5.5V rail. The operating temperature range of -40°C to +150°C makes it suitable for factory floor equipment.
Recomendado
Telematics and Infotainment
In telematics and infotainment systems, the L9779-TR provides clean power to the application processor and communication modules. The 5V output powers the main processor, while the 3.3V rail supplies the GPS and cellular modules. The low output noise ensures minimal interference with RF circuits. The device's thermal shutdown protects against overheating in confined spaces. The standby mode helps reduce battery drain when the vehicle is parked.
Recomendado
Battery Management Systems
The L9779-TR is used in battery management systems to power the monitoring IC and communication interfaces. Its wide input range allows operation from the battery pack voltage. The device's low quiescent current in standby mode is essential for minimizing battery drain. The overcurrent protection prevents damage during fault conditions. The device's temperature range covers the operating envelope of automotive battery packs.
Recomendado
Resumen de productos recomendados
Datos de referencia de ingeniería para L9779-TR — comparación, orientación de diseño e información de cumplimiento.
Guía de selección
Comparación con alternativas
| Parámetro | Este producto | L9779 | TLE4267 | MC7805CD2T |
|---|---|---|---|---|
| Package | PowerSO-20 | PowerSO-20 | PowerSO-20 | D2PAK |
| Brand | STMicroelectronics | STMicroelectronics | Infineon | onsemi |
| Output Voltage 1 | 5V | 5V | 5V | 5V |
| Output Voltage 2 | 3.3V | 3.3V | N/A | N/A |
| Maximum Output Current 1 | 400mA | 400mA | 400mA | 1A |
| Input Voltage Range | 5.5V to 18V | 5.5V to 18V | 5.5V to 42V | 7V to 25V |
| Dropout Voltage | 0.5V | 0.5V | 0.5V | 2V |
| Quiescent Current (standby) | 50µA | 50µA | 70µA | 6mA |
Diferenciadores clave
- Dual output (5V and 3.3V) in a single package (frente a TLE4267)
- Low standby quiescent current of 50µA (frente a MC7805CD2T)
- Wide input voltage range of 5.5V to 18V (frente a MC7805CD2T)
Notas de diseño
Place input and output capacitors as close to the VCC and VOUT pins as possible. Use a minimum of 10µF on the input and 22µF on the output for stability. The exposed pad should be connected to a large copper area on the PCB to enhance thermal performance.
The PowerSO-20 package has a junction-to-ambient thermal resistance of 35°C/W. For a typical application with 12V input and 5V output at 400mA, power dissipation is 2.8W, resulting in a temperature rise of 98°C. Ensure adequate copper area or airflow to keep the junction temperature below 150°C.
Do not exceed the maximum input voltage of 18V. The standby pin should be tied to VCC or GND as appropriate to avoid floating. Ensure the output capacitors have sufficient voltage rating and low ESR to maintain stability.
Información de cumplimiento
AEC-Q100 qualified for automotive applications. RoHS compliant per STMicroelectronics product page.
