LM5117MHX/NOPB - 5.5-65V Synchronous Buck Controller | Texas Instruments
MPN: LM5117MHX/NOPB β Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $3.42 | $3.42 |
| 10 | $3.08 | $30.80 |
| 100 | $2.74 | $274.00 |
| 500 | $2.47 | $1,235.00 |
| 1,000 | $2.19 | $2,190.00 |
Drop-in alternatives for LM5117MHX/NOPB 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:
LM5117PMHX/NOPB
β Drop-Inπ Reference alternative (not in catalog)
LM5117QPMHX/NOPB
β Drop-Inπ Reference alternative (not in catalog)
LM25117PMHX/NOPB
β Drop-Inπ Reference alternative (not in catalog)
LM5117MHX/NOPB
β Drop-Inβ In Stock
$2.19 / Unit
View Datasheet βLM5117PMHE/NOPB
β Drop-Inπ Reference alternative (not in catalog)
LM5117QPMHE/NOPB
β Drop-Inπ Reference alternative (not in catalog)
LM25117QPMHX/NOPB
β Drop-Inπ Reference alternative (not in catalog)
LM5117MHX/NOPB
β Drop-Inβ In Stock
$2.19 / Unit
View Datasheet βLM5117MHX/NOPB Maximum Ratings & Electrical Characteristics
| Function | Step-Down (Buck) Controller |
| Output Type | Single |
| Input Voltage Range | 5.5V to 65V |
| Output Voltage Range | 1.5V to 60V (adjustable) |
| Switching Frequency | 50kHz to 750kHz |
| Control Method | Current Mode (emulated ramp) |
| Number of Outputs | 1 |
| Package | HTSSOP-20 (PWP) |
| Operating Temperature Range | -40Β°C to +125Β°C |
| Analog Current Monitor | Yes |
| Soft-Start | Yes (programmable) |
| Overcurrent Protection | Hiccup mode |
| Thermal Shutdown | Yes |
| RoHS Status | Compliant |
| Mounting Type | Surface Mount |
LM5117MHX/NOPB Pin Configuration
| Pin 1 | VIN β Input supply voltage |
| Pin 2 | VCC β Internal regulator output |
| Pin 3 | BST β Bootstrap for high-side gate driver |
| Pin 4 | HO β High-side gate drive output |
| Pin 5 | SW β Switch node |
| Pin 6 | LO β Low-side gate drive output |
| Pin 7 | PGND β Power ground |
| Pin 8 | CS β Current sense input |
| Pin 9 | FB β Feedback input |
| Pin 10 | COMP β Compensation network |
| Pin 11 | SS β Soft-start programming |
| Pin 12 | RT β Switching frequency set |
| Pin 13 | AGND β Analog ground |
| Pin 14 | EN β Enable input |
| Pin 15 | CM β Current monitor output |
| Pin 16 | NC β No connect |
| Pin 17 | NC β No connect |
| Pin 18 | NC β No connect |
| Pin 19 | NC β No connect |
| Pin 20 | NC β No connect |
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
LM5117MHX/NOPB is suitable for 6 applications: Industrial Power Supplies, Automotive Electronics, Telecom and Networking Equipment, Battery-Powered Systems, Server and Datacenter Power, General-Purpose Step-Down Converters.
Industrial Power Supplies
The LM5117MHX/NOPB is ideal for industrial power supplies that require a wide input voltage range and high efficiency. With an input range of 5.5V to 65V, it can handle 12V, 24V, and 48V rails commonly found in factory automation, test equipment, and process control. The current mode control with emulated ramp ensures stable operation under varying load conditions, while the analog current monitor enables precise current sensing for system protection. The programmable switching frequency allows optimization for efficiency or EMI, making it a versatile choice for robust industrial designs.
Recommended
Automotive Electronics
In automotive applications, the LM5117MHX/NOPB provides a reliable solution for step-down conversion from the vehicle's 12V or 24V battery bus. Its wide input range accommodates load dump transients up to 65V, and the operating temperature range of -40Β°C to +125Β°C meets automotive environmental requirements. The device's current mode control ensures stable operation during rapid load changes, such as those from infotainment systems, lighting, and sensors. For full AEC-Q100 compliance, the LM5117QPMHX/NOPB variant is recommended, offering the same performance with automotive-grade qualification.
Recommended
Telecom and Networking Equipment
The LM5117MHX/NOPB is well-suited for telecom and networking equipment that operates from 48V backplane rails. Its 5.5V to 65V input range directly handles 48V inputs with margin for transients, and the synchronous buck topology achieves high efficiency, reducing thermal stress in dense equipment racks. The analog current monitor is valuable for load monitoring and fault detection in redundant power architectures. The programmable switching frequency allows designers to place switching noise outside sensitive communication bands, improving system EMI performance.
Recommended
Battery-Powered Systems
For battery-powered systems, the LM5117MHX/NOPB efficiently steps down battery voltages to regulated rails, extending battery life. Its wide input range supports various battery chemistries, from 2-cell Li-ion (up to 8.4V) to 48V lead-acid packs. The low quiescent current and high efficiency at light loads help maximize runtime. The device's soft-start feature prevents inrush current during startup, protecting the battery and downstream components. The analog current monitor can be used to implement fuel gauging or battery health monitoring.
Recommended
Server and Datacenter Power
In server and datacenter applications, the LM5117MHX/NOPB can be used to generate intermediate bus voltages from a 48V distribution rail. Its high efficiency reduces power loss and cooling requirements, contributing to overall energy savings. The current mode control provides fast transient response to handle dynamic loads from processors and memory. The analog current monitor enables accurate power monitoring for management systems. The device's robust protection features, including hiccup mode overcurrent and thermal shutdown, ensure reliable operation in high-availability environments.
Recommended
General-Purpose Step-Down Converters
The LM5117MHX/NOPB serves as a flexible building block for general-purpose step-down converters in a wide range of applications. Its adjustable output voltage and programmable switching frequency allow it to be tailored to specific requirements, from low-voltage logic supplies to higher-voltage industrial rails. The external MOSFETs enable scaling to different power levels, making it suitable for both low-power and high-power designs. The device's ease of compensation and comprehensive protection features simplify the design process, reducing time-to-market.
Recommended
Recommended Products Summary
Engineering reference data for LM5117MHX/NOPB β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | LM5117PMHX/NOPB | LM5117QPMHX/NOPB | LM25117PMHX/NOPB |
|---|---|---|---|---|
| Package | HTSSOP-20 (PWP) | HTSSOP-20 (PWP) | HTSSOP-20 (PWP) | HTSSOP-20 (PWP) |
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments |
| Input Voltage Range | 5.5V to 65V | 5.5V to 65V | 5.5V to 65V | 4.5V to 42V |
| Switching Frequency | 50kHz to 750kHz | 50kHz to 750kHz | 50kHz to 750kHz | 50kHz to 750kHz |
| Control Method | Current Mode (emulated ramp) | Current Mode (emulated ramp) | Current Mode (emulated ramp) | Current Mode (emulated ramp) |
| Analog Current Monitor | Yes | Yes | Yes | Yes |
| Automotive Grade | No | No | Yes (AEC-Q100) | No |
| Operating Temperature Range | -40Β°C to +125Β°C | -40Β°C to +125Β°C | -40Β°C to +125Β°C | -40Β°C to +125Β°C |
Key Differentiators
- Wide input voltage range up to 65V (vs LM25117PMHX/NOPB)
- Analog current monitor output (vs LM25117PMHX/NOPB)
- Automotive-grade variant available (vs LM5117PMHX/NOPB)
Design Notes
For optimal performance, place the input capacitor, high-side MOSFET, low-side MOSFET, and output inductor in a tight loop to minimize parasitic inductance. Use a solid ground plane and separate power ground from analog ground, connecting them at a single point. Keep the bootstrap capacitor close to the BST and SW pins. Refer to the LM5117 datasheet layout guidelines for detailed recommendations.
The HTSSOP-20 package has an exposed thermal pad that must be soldered to a copper area on the PCB for effective heat dissipation. The power dissipation in the controller itself is relatively low, but the external MOSFETs and inductor may generate significant heat. Ensure adequate copper area and airflow for the power stage components. The thermal pad should be connected to the ground plane with multiple vias to improve thermal conductivity.
A common pitfall is improper selection of the external MOSFETs. Ensure the gate drive voltage (VCC) is sufficient to fully enhance the MOSFETs, and consider the total gate charge to avoid excessive switching losses. Also, the current sense resistor (if used) must be placed correctly to avoid noise pickup. The soft-start capacitor should be sized to prevent output overshoot during startup. Always verify the loop compensation using the guidelines in the datasheet.
Compliance Information
RoHS compliant per TI product page. Not AEC-Q100 qualified; use LM5117QPMHX/NOPB for automotive.
