LM61440 - 4A, 36V Low EMI Synchronous Buck Converter | TI
MPN: LM61440 β Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $2.85 | $2.85 |
| 10 | $2.56 | $25.60 |
| 100 | $2.28 | $228.00 |
| 500 | $2.05 | $1,025.00 |
| 1,000 | $1.82 | $1,820.00 |
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)
LM61440AASQRJRRQ1
β Drop-Inπ Reference alternative (not in catalog)
LM61440AANRJRR
β Drop-Inπ Reference alternative (not in catalog)
LM61440 Maximum Ratings & Electrical Characteristics
| Input Voltage Range | 3.0 V to 36 V |
| Output Current | 4 A |
| Output Voltage Range | 1 V to 36 V (adjustable) |
| Transient Tolerance | 42 V |
| Switching Frequency | [DATA_NEEDED: switching frequency] |
| Efficiency | [DATA_NEEDED: efficiency] |
| Control Architecture | Current-mode control |
| Integrated MOSFETs | Yes (high-side and low-side) |
| Soft Recovery | Yes |
| Spread Spectrum | Pseudo-random |
| SW Node Rise Time | Adjustable |
| Package | 14-Pin 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 | EN β Enable pin (active high) |
| Pin 3 | RT β Switching frequency timing resistor |
| Pin 4 | FB β Feedback pin for output voltage regulation |
| Pin 5 | COMP β Compensation pin |
| Pin 6 | GND β Ground |
| Pin 7 | SW β Switch node output |
| Pin 8 | BST β Bootstrap capacitor connection |
| Pin 9 | VOUT β Output voltage sense |
| Pin 10 | PG β Power good indicator |
| Pin 11 | SS β Soft-start timing |
| Pin 12 | MODE β Mode selection (FPWM or auto) |
| Pin 13 | GND β Ground |
| Pin 14 | PAD β Exposed thermal pad (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
LM61440 is suitable for 6 applications: Automotive Power Supplies, Industrial Control Systems, Telecom and Networking Equipment, Point-of-Load (POL) Converters, Battery-Powered Devices, LED Lighting Systems.
Automotive Power Supplies
The LM61440 is ideal for automotive power supplies due to its wide input range (3.0V to 36V) and 42V transient tolerance, which handle load dump and cold-crank conditions. Its low-EMI features help meet automotive EMC standards, and the AEC-Q100 qualified variant ensures reliability. The 4A output current can power infotainment systems, ADAS modules, and body control units. The soft recovery feature prevents output overshoot during voltage dips, protecting sensitive electronics.
Recommended
Industrial Control Systems
In industrial control systems, the LM61440 provides a robust power solution with its 3.0V to 36V input range and 4A output. It can operate from 24V industrial buses with ample headroom, and the 42V transient tolerance protects against voltage spikes from inductive loads. The current-mode control ensures stable operation with fast transient response, making it suitable for PLCs, motor drives, and factory automation. The low-EMI design reduces interference with sensitive control signals.
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 features, including pseudo-random spread spectrum and adjustable SW node rise time, help minimize interference with high-speed data lines. The 4A output can power FPGAs, ASICs, and line cards. The wide input range accommodates various bus voltages, and the integrated MOSFETs reduce board space, enabling compact designs for routers, switches, and base stations.
Recommended
Point-of-Load (POL) Converters
The LM61440 is an excellent choice for point-of-load converters, providing up to 4A from a 3.0V to 36V input. Its adjustable output down to 1V makes it suitable for powering low-voltage digital cores, memory, and I/O. The current-mode control with integrated compensation simplifies design, and the small 14-pin PowerVFQFN package saves board space. The soft recovery feature ensures smooth startup, and the low-EMI design reduces noise coupling to nearby circuits.
Recommended
Battery-Powered Devices
For battery-powered devices, the LM61440's wide input range (3.0V to 36V) allows operation from various battery chemistries, including Li-ion and lead-acid. The high efficiency of the synchronous architecture extends battery life, and the low quiescent current (if specified) helps in standby modes. The 4A output can handle peak loads, while the soft recovery prevents output overshoot during battery voltage drops. The small package is ideal for portable and wearable devices.
Recommended
LED Lighting Systems
The LM61440 can be used in LED lighting systems to provide a regulated voltage or current to LED drivers. Its wide input range (3.0V to 36V) accommodates various supply voltages, and the 4A output can drive multiple LED strings. The low-EMI features are beneficial in lighting applications to avoid interference with communication systems. The soft recovery ensures smooth dimming transitions, and the small package allows integration into compact lighting fixtures.
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 | LM61440AASQRJRRQ1 | LM61440AANRJRR | TPS54360DDAR | TPS5450DDAR |
|---|---|---|---|---|---|---|
| Package | 14-Pin PowerVFQFN (RJR) | 14-Pin PowerVFQFN (RJR) | 14-Pin PowerVFQFN (RJR) | 14-Pin PowerVFQFN (RJR) | SOIC-8 | SOIC-8 |
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments |
| Input Voltage Range | 3.0V to 36V | 3.0V to 36V | 3.0V to 36V | 3.0V to 36V | 4.5V to 60V | 5.5V to 36V |
| Output Current | 4A | 4A | 4A | 4A | 3.5A | 5A |
| Transient Tolerance | 42V | 42V | 42V | 42V | 65V | 36V |
| Low EMI Features | Yes (spread spectrum, adjustable SW rise time) | Yes | Yes | Yes | No | No |
| Automotive Grade | No (standard) | Yes (AEC-Q100) | Yes (AEC-Q100) | No | No | No |
| Control Architecture | Current-mode | Current-mode | Current-mode | Current-mode | Current-mode | Current-mode |
Key Differentiators
- Low EMI design with pseudo-random spread spectrum (vs TPS54360DDAR)
- Soft recovery from dropout (vs TPS5450DDAR)
- 42V transient tolerance (vs TPS5450DDAR)
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 a solid ground plane and connect the exposed pad (pin 14) directly to the ground plane with multiple vias to enhance thermal dissipation. Keep the SW node trace short and wide to minimize parasitic inductance and EMI.
The LM61440 in the 14-pin PowerVFQFN package can dissipate significant power at high input-output voltage differentials. For example, at VIN=24V, VOUT=5V, and 4A load, power dissipation is approximately 76W, which is not feasible without a heatsink. Ensure adequate copper area and airflow, or reduce output current to stay within thermal limits. The exposed pad must be soldered to a large copper pour for heat sinking.
Do not exceed the absolute maximum input voltage of 42V. The soft recovery feature prevents output overshoot during dropout, but ensure the input supply can handle transient currents. Use a bootstrap capacitor (100nF) between BST and SW pins. The RT pin sets the switching frequency; choose a resistor value per the datasheet to avoid instability. Verify the feedback resistor divider for accurate output voltage.
Compliance Information
RoHS compliant per TI product page. AEC-Q100 qualified for LM61440-Q1 variant.
