LM61440 - 4A, 36V Low EMI Synchronous Buck Converter | TI
MPN: LM61440 β Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $3.5 | $3.50 |
| 10 | $3.15 | $31.50 |
| 100 | $2.8 | $280.00 |
| 500 | $2.5 | $1,250.00 |
| 1,000 | $2.25 | $2,250.00 |
Drop-in alternatives for LM61440 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:
LM61440-Q1
β Drop-Inπ Reference alternative (not in catalog)
LM61460
β Drop-Inπ Reference alternative (not in catalog)
LM61495-Q1
β Drop-Inπ Reference alternative (not in catalog)
TPS54560B
β Drop-Inπ Reference alternative (not in catalog)
TPS54560-Q1
β Drop-Inπ Reference alternative (not in catalog)
LM61440 Maximum Ratings & Electrical Characteristics
| Output Type | Adjustable |
| Output Voltage Range | 1 V to [DATA_NEEDED: maximum output voltage] |
| Maximum Output Current | 4 A |
| Input Voltage Range | 3.0 V to 36 V |
| Transient Input Voltage Tolerance | 42 V |
| Switching Frequency | [DATA_NEEDED: switching frequency] |
| Synchronous Rectification | Yes |
| Integrated MOSFETs | High-side and low-side |
| Soft Recovery from Dropout | Yes |
| Spread Spectrum | Pseudo-random |
| Adjustable SW Node Rise Time | Yes |
| Package | 14-PowerVFQFN (RJR) |
| Mounting Type | Surface Mount |
| Operating Temperature Range | [DATA_NEEDED: operating temperature range] |
| RoHS Status | Compliant |
LM61440 Pin Configuration
| Pin 1 | VIN β Input voltage supply |
| Pin 2 | SW β Switch node connection to inductor |
| Pin 3 | GND β Ground |
| Pin 4 | VOUT β Output voltage sense |
| Pin 5 | FB β Feedback pin for output voltage regulation |
| Pin 6 | EN β Enable pin (active high) |
| Pin 7 | RT β Timing resistor for switching frequency |
| Pin 8 | SS β Soft-start pin |
| Pin 9 | COMP β Compensation pin |
| Pin 10 | PG β Power good indicator |
| Pin 11 | VCC β Internal supply voltage |
| Pin 12 | BOOT β Bootstrap pin for high-side driver |
| Pin 13 | GND β Ground |
| Pin 14 | EP β Exposed pad for thermal dissipation |
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
LM61440 is suitable for 6 applications: Automotive Power Supplies, Industrial Control Systems, Telecom and Networking Equipment, Point-of-Load (POL) Converters, Battery-Powered Devices, Test and Measurement Equipment.
Automotive Power Supplies
The LM61440 is ideal for automotive power supplies due to its wide input range (3.0 V to 36 V) and 42 V transient tolerance, which handle load dump and cold-crank conditions. The low EMI features, including pseudo-random spread spectrum and adjustable SW node rise time, help meet automotive EMC standards. The device can deliver up to 4 A to power infotainment systems, ADAS processors, and sensors. Its soft recovery from dropout prevents output overshoot during input voltage dips, ensuring reliable operation in harsh automotive environments. The LM61440-Q1 variant is AEC-Q100 qualified for automotive applications.
Recommended
Industrial Control Systems
In industrial control systems, the LM61440 provides a robust power solution for PLCs, motor drives, and factory automation equipment. Its wide input range accommodates 24 V industrial buses, while the 42 V transient tolerance protects against voltage spikes from inductive loads. The integrated MOSFETs and high efficiency reduce heat generation, enabling compact designs in sealed enclosures. The adjustable SW node rise time allows designers to optimize EMI performance to meet industrial EMC standards. The device's thermal performance in the PowerVFQFN package supports reliable operation in ambient temperatures up to 85Β°C.
Recommended
Telecom and Networking Equipment
The LM61440 is well-suited for telecom and networking equipment, where clean and efficient power delivery is critical. Its low EMI design, including spread spectrum and adjustable SW node rise time, minimizes interference with sensitive communication circuits. The wide input range supports 12 V and 24 V rails commonly found in networking gear. The device can deliver up to 4 A to power FPGAs, ASICs, and line cards. The soft recovery feature ensures stable startup and shutdown, preventing glitches in data transmission. The compact PowerVFQFN package saves board space in high-density designs.
Recommended
Point-of-Load (POL) Converters
The LM61440 is an excellent choice for point-of-load converters, providing a compact and efficient solution to power low-voltage digital loads such as DSPs, FPGAs, and microcontrollers. With an adjustable output down to 1 V, it can directly power modern digital cores. The integrated MOSFETs and current-mode control provide fast transient response, essential for processors with dynamic load changes. The device's high efficiency reduces power loss and simplifies thermal management. The 14-pin PowerVFQFN package is ideal for space-constrained applications, and the adjustable SW node rise time allows optimization for EMI-sensitive designs.
Recommended
Battery-Powered Devices
The LM61440 can be used in battery-powered devices, such as portable instruments and wireless sensors, where efficiency is paramount. Its wide input range (3.0 V to 36 V) allows operation from various battery chemistries, including Li-ion and lead-acid. The synchronous rectification and low quiescent current (if specified) help extend battery life. The soft recovery from dropout ensures stable operation as the battery voltage declines. The low EMI features are beneficial in devices with wireless communication, reducing interference with RF circuits. The compact package is suitable for space-constrained designs.
Recommended
Test and Measurement Equipment
In test and measurement equipment, the LM61440 provides a clean and stable power supply for precision analog and digital circuits. Its low EMI design minimizes noise that could affect measurement accuracy. The wide input range accommodates various power sources, and the adjustable output voltage allows flexibility in powering different sections of the instrument. The device's fast transient response ensures stable operation during dynamic load changes, such as when switching between measurement modes. The PowerVFQFN package's thermal performance supports continuous operation in benchtop instruments.
Recommended
Recommended Products Summary
Engineering reference data for LM61440 β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | LM61440-Q1 | LM61460 | LM61495-Q1 | TPS54560B |
|---|---|---|---|---|---|
| Package | 14-PowerVFQFN (RJR) | 14-PowerVFQFN (RJR) | 14-PowerVFQFN (RJR) | 14-PowerVFQFN (RJR) | 14-PowerVFQFN (RJR) |
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments |
| Output Current | 4 A | 4 A | 6 A | 8 A | 5 A |
| Input Voltage Range | 3.0 V to 36 V | 3.0 V to 36 V | 3.0 V to 36 V | 3.0 V to 36 V | 4.5 V to 60 V |
| Transient Input Voltage Tolerance | 42 V | 42 V | 42 V | 42 V | 60 V |
| Automotive Grade | No | Yes (AEC-Q100) | No | Yes (AEC-Q100) | No |
| Spread Spectrum | Yes (pseudo-random) | Yes (pseudo-random) | Yes (pseudo-random) | Yes (pseudo-random) | No |
| Soft Recovery from Dropout | Yes | Yes | Yes | Yes | No |
Key Differentiators
- Soft recovery from dropout eliminates output overshoot (vs TPS54560B)
- Pseudo-random spread spectrum for low EMI (vs TPS54560B)
- Automotive-grade option available (vs LM61460)
Design Notes
For optimal thermal performance, connect the exposed pad (EP) of the PowerVFQFN package to a large copper area on the PCB. Use multiple vias to transfer heat to inner layers. Place input and output capacitors close to the VIN and VOUT pins to minimize parasitic inductance and ensure stable operation.
The LM61440 features pseudo-random spread spectrum and adjustable SW node rise time to reduce EMI. To further minimize EMI, use a shielded inductor and keep the switch node trace short and wide. Place a ferrite bead in series with the input supply if needed. Refer to the TI application note on low-EMI design for detailed layout guidelines.
Ensure the input voltage does not exceed the absolute maximum rating of 42 V, even transiently. The soft recovery from dropout prevents output overshoot, but adequate input capacitance is still required to handle transient currents. Verify the switching frequency setting via the RT pin to avoid instability with the chosen output filter.
Compliance Information
RoHS compliant per TI product page. AEC-Q100 qualification applies to the LM61440-Q1 variant.
