LM5116MHX: High-Efficiency DC-DC Switching Controller IC | Features & Applications
LM5116MHX: Advanced DC-DC Switching Controller for High-Efficiency Power Conversion
The LM5116MHX from Texas Instruments (formerly National Semiconductor) represents the pinnacle of switching controller technology, engineered to deliver exceptional performance in voltage regulation for mission-critical applications. As a premier solution in the PMIC - Voltage Regulators - DC DC Switching Controllers category, this IC combines robust power handling with intelligent control features, making it indispensable for modern power supply designs.
Comprehensive Technical Overview
Core Specifications
- Topology: Synchronous Buck Converter with Current-Mode Control
- Input Voltage Range: 6V to 100V (75V non-repetitive maximum)
- Output Current: Configurable up to 10A with external components
- Switching Frequencies: Programmable 200kHz or 535kHz ( 10% accuracy)
- Efficiency: Up to 95% with synchronous rectification
- Package: 20-pin HTSSOP with exposed thermal pad
Advanced Control Features
The LM5116MHX integrates multiple control mechanisms for precision power management:
- Adaptive Gate Drive: Adjusts MOSFET drive strength (1A/4A) for optimal switching losses
- Programmable Soft-Start: 1ms to 10ms ramp-up time for inrush current control
- Cycle-by-Cycle Current Limiting: Provides robust overload protection
- External Synchronization: Phase-lock capability ( 20% frequency range)
- Power Good Indicator: Open-drain output for system monitoring
Design Advantages
Thermal Management
The device incorporates multiple thermal protection features:
- Precision thermal shutdown (160 C typical with 20 C hysteresis)
- Exposed pad for enhanced PCB heat dissipation
- Derating curves provided for high-temperature operation
Application-Specific Optimization
Designers benefit from specialized configurations for:
- Automotive Systems: Compliant with ISO-7637 transients
- Industrial Power: Tolerant to 100V load dump conditions
- Telecom Infrastructure: -40 C to +125 C junction temperature range
Comparative Performance Data
| Parameter | LM5116MHX | Competitor A | Competitor B |
|---|---|---|---|
| Input Range | 6-100V | 4.5-60V | 8-42V |
| Efficiency @ 24VIN | 94% | 91% | 89% |
| Quiescent Current | 2.5mA | 3.8mA | 4.2mA |
Implementation Guidelines
Layout Recommendations
- Use separate power and signal ground planes
- Minimize loop area in high-current paths
- Place bootstrap components within 10mm of IC
- Utilize all thermal vias under exposed pad
Component Selection
- MOSFETs: Select based on RDS(ON) and Qg parameters
- Inductors: 4.7 H to 22 H with saturation current rating
- Capacitors: Low-ESR ceramic (X7R/X5R) for input/output
Frequently Asked Questions
Q: Can the LM5116MHX operate in forced PWM mode?
A: Yes, the device supports both PFM and forced PWM operation through MODE pin configuration.
Q: What is the minimum controllable on-time?
A: The IC features 100ns typical minimum on-time, enabling high step-down ratios.
Q: Is external compensation required?
A: Yes, the device uses Type III compensation network for optimal transient response.
Purchasing Information
The LM5116MHX is available through authorized distributors with the following options:
- Single units: 20-pin HTSSOP tube packaging
- Reel quantities: 2500 pieces per reel
- Evaluation board: LM5116MHX-EVM available
For engineers seeking unparalleled performance in high-voltage DC-DC conversion, the LM5116MHX delivers industry-leading specifications with Texas Instruments' renowned reliability. Its combination of wide input range, advanced control features, and robust thermal performance makes it the optimal choice for demanding power applications across multiple industries.