L7983TR - 38V 3A Step-Down Switching Regulator | STMicroelectronics
MPN: L7983TR β Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $1.85 | $1.85 |
| 10 | $1.66 | $16.60 |
| 100 | $1.48 | $148.00 |
| 500 | $1.33 | $665.00 |
| 1,000 | $1.2 | $1,200.00 |
Drop-in alternatives for L7983TR β same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
L7983
β Drop-Inπ Reference alternative (not in catalog)
L7986TR
β Drop-Inβ 99,999 In Stock
$1.85 / Unit
View Datasheet βTPS5430
β Drop-Inπ Reference alternative (not in catalog)
NCP3063
β Drop-Inπ Reference alternative (not in catalog)
L7983TR Maximum Ratings & Electrical Characteristics
| Output Type | Adjustable |
| Output Voltage Range | 0.6 V to 38 V |
| Maximum Output Current | 3 A |
| Input Voltage Range | 4.5 V to 38 V |
| Switching Frequency | 250 kHz |
| Efficiency | 90% typical at 12V to 5V, 2A |
| Control Architecture | Current Mode |
| Quiescent Current | 2 mA |
| Operating Temperature | -40C to +150C |
| Package | SOIC-8 (SO-8) |
| Mounting Type | Surface Mount |
| MSL Level | 3 (168 hours) |
| RoHS Status | Compliant |
| Enable Pin | Yes (active-high) |
| Protection Features | Overcurrent, Thermal Shutdown |
L7983TR Pin Configuration
| Pin 1 | VIN β Input supply voltage |
| Pin 2 | GND β Ground |
| Pin 3 | EN β Enable (active high) |
| Pin 4 | FB β Feedback voltage |
| Pin 5 | COMP β Compensation |
| Pin 6 | SW β Switch node |
| Pin 7 | VOUT β Output voltage |
| Pin 8 | GND β Ground |
Safe Operating Area (SOA) & Thermal Characteristics
No official SOA curve available for this component. Always operate within absolute maximum ratings specified in the datasheet. Ensure adequate cooling and derate as needed.
Typical Applications
L7983TR is suitable for 6 applications: Industrial Power Supplies, Automotive Systems, Distributed Power Architectures, Point-of-Load (POL) Converters, Battery-Powered Equipment, Telecom and Networking Equipment.
Industrial Power Supplies
The L7983TR is ideal for industrial power supplies that require a wide input voltage range (4.5V to 38V) and output currents up to 3A. Its high efficiency (90% typical) reduces heat dissipation, making it suitable for enclosed industrial enclosures. The device can step down 24V bus voltages to 5V or 3.3V for logic circuits, sensors, and microcontrollers. The enable pin allows for power sequencing in multi-rail systems, ensuring proper startup order. The fixed 250kHz switching frequency simplifies EMI filtering, which is critical in industrial environments with strict electromagnetic compatibility requirements. The current-mode control provides stable operation under varying load conditions, which is common in industrial automation where motors and actuators cause load transients. The SOIC-8 package is easy to assemble and replace, reducing maintenance costs. Overall, the L7983TR offers a robust and efficient solution for industrial power conversion.
Recommended
Automotive Systems
In automotive systems, the L7983TR can be used to step down the 12V battery voltage to 5V or 3.3V for infotainment systems, sensors, and control units. The wide input voltage range (4.5V to 38V) accommodates load dump and cold-crank conditions, which can cause voltage spikes and dips. The operating temperature range of -40C to +150C ensures reliable operation in harsh automotive environments. The high efficiency reduces power loss, which is important for battery life in electric vehicles. The enable pin allows for power sequencing, ensuring that sensitive electronics are powered up in the correct order. The current-mode control provides fast transient response, which is essential for handling sudden load changes from motors and actuators. While the L7983TR is not AEC-Q100 qualified, it can be used in non-safety-critical automotive applications. For safety-critical applications, consider automotive-grade alternatives.
Recommended
Distributed Power Architectures
The L7983TR is well-suited for distributed power architectures where a central power bus (e.g., 24V) is stepped down to various lower voltages at the point of load. Its 3A output current can power FPGAs, ASICs, and other high-current digital loads. The wide input voltage range allows it to be used in systems with varying bus voltages. The high efficiency reduces the need for heatsinking, enabling compact designs. The fixed 250kHz switching frequency allows for the use of small inductors and capacitors, reducing board space. The enable pin enables power sequencing, which is critical in complex systems with multiple voltage rails. The current-mode control ensures stable operation even with dynamic loads, which is common in digital systems. The SOIC-8 package is widely available and cost-effective, making it a popular choice for distributed power designs.
Recommended
Point-of-Load (POL) Converters
The L7983TR is an excellent choice for point-of-load (POL) converters that need to provide a regulated voltage close to the load. Its 3A output current is sufficient for many digital loads, such as microprocessors, FPGAs, and memory. The wide input voltage range (4.5V to 38V) allows it to be used in systems with intermediate bus voltages. The high efficiency (90% typical) minimizes power loss and heat generation, which is critical in dense PCB layouts. The fixed 250kHz switching frequency enables the use of small external components, reducing the overall solution size. The enable pin allows for power sequencing, ensuring that the load is powered up in the correct order. The current-mode control provides excellent line and load regulation, ensuring a stable output voltage. The SOIC-8 package is easy to integrate into existing designs, making it a versatile POL solution.
Recommended
Battery-Powered Equipment
The L7983TR is suitable for battery-powered equipment that requires efficient step-down conversion to extend battery life. Its high efficiency (90% typical) reduces power loss, which is critical for battery-operated devices. The wide input voltage range (4.5V to 38V) allows it to operate from various battery configurations, such as 2S to 8S Li-ion packs. The low quiescent current (2mA) helps minimize standby power consumption, extending battery life in sleep modes. The enable pin can be used to shut down the regulator when not needed, further reducing power consumption. The current-mode control provides stable operation as the battery voltage decreases over time. The SOIC-8 package is compact and lightweight, making it suitable for portable devices. The fixed 250kHz switching frequency allows for small external components, reducing the overall footprint.
Recommended
Telecom and Networking Equipment
The L7983TR is used in telecom and networking equipment to step down 48V or 24V bus voltages to lower voltages for line cards, switches, and routers. Its wide input voltage range (4.5V to 38V) covers common telecom bus voltages. The 3A output current can power multiple loads, such as FPGAs, ASICs, and PHY chips. The high efficiency reduces heat generation, which is important in densely packed equipment racks. The fixed 250kHz switching frequency simplifies EMI filtering, which is critical in telecom applications with strict EMC standards. The enable pin allows for power sequencing, ensuring that line cards are powered up in the correct order. The current-mode control provides stable operation under varying load conditions, which is common in networking equipment with bursty traffic. The SOIC-8 package is widely used and easy to source, making it a reliable choice for telecom designs.
Recommended
Recommended Products Summary
Engineering reference data for L7983TR β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | L7983 | L7986TR | TPS5430 | NCP3063 |
|---|---|---|---|---|---|
| Package | SOIC-8 | SOIC-8 - same | SOIC-8 - same | SOIC-8 - same | SOIC-8 - same |
| Brand | STMicroelectronics | STMicroelectronics | STMicroelectronics | Texas Instruments | onsemi |
| Input Voltage Range | 4.5V to 38V | 4.5V to 38V | 4.5V to 38V | 5.5V to 36V | 3V to 40V |
| Output Current | 3A | 3A | 3A | 3A | 1.5A |
| Switching Frequency | 250kHz | 250kHz | 250kHz | 500kHz | 150kHz |
| Enable Pin | Yes | Yes | Yes | Yes | No |
| Quiescent Current | 2mA | 2mA | 2mA | 3mA | 2.5mA |
| Operating Temperature | -40C to +150C | -40C to +150C | -40C to +150C | -40C to +125C | -40C to +125C |
Key Differentiators
- Wide input voltage range (4.5V to 38V) (vs TPS5430)
- Higher output current (3A) compared to NCP3063 (vs NCP3063)
- Enable pin for power sequencing (vs NCP3063)
Design Notes
For optimal performance, place the input capacitor (10uF) and output capacitor (22uF) as close to the VIN and VOUT pins as possible. Use short, wide traces for high-current paths to minimize parasitic inductance and resistance. The feedback resistor divider should be placed away from the inductor to avoid noise coupling. A solid ground plane is essential for thermal management and EMI reduction.
The L7983TR can dissipate significant power at high input voltages and output currents. For example, at VIN=24V, VOUT=5V, and 3A load, the power dissipation is approximately 57W (assuming 90% efficiency). The SOIC-8 package has a thermal resistance of about 100C/W (theta_JA), so a heatsink or large copper area is required to keep the junction temperature below the maximum rating. Use a 2-ounce copper pour on the PCB to improve heat dissipation.
Do not exceed the absolute maximum input voltage of 38V. Ensure the inductor saturation current rating is higher than the peak switch current to avoid core saturation. The feedback resistor divider should use 1% tolerance resistors to maintain output voltage accuracy. The compensation network (COMP pin) must be designed according to the datasheet guidelines to ensure stability. Avoid running the device without a load, as this can cause output voltage overshoot.
Compliance Information
RoHS compliant per STMicroelectronics product page. Not AEC-Q100 qualified. Lead-free per datasheet.
