Texas Instruments LM5108DRCT

Overview

LM5108DRCT from Texas Instruments is a 100-V half-bridge gate driver IC designed to control two N-channel MOSFETs in high-side/low-side configuration for synchronous buck, LLC, and active-clamp forward topologies. It delivers 2.6-A sink / 1.6-A source peak output current, features integrated bootstrap diode, 20-ns propagation delay, and 1-ns delay matching-enabling precise dead-time control in motor drives and power tools.

For engineers reviewing the LM5108DRCT datasheet, LM5108DRCT pinout, LM5108DRCT application, or LM5108DRCT equivalent, key selection criteria include its 100-V HS voltage rating, interlock protection against shoot-through, 5-V UVLO threshold, 3-mm × 3-mm VSON-10 package, and compatibility with TTL/CMOS inputs in noise-prone industrial environments.

Technical Context

The LM5108DRCT implements independent TTL/CMOS-compatible HI and LI inputs with 250-kΩ internal pulldown resistors and 0.7-V input hysteresis, enabling robust operation in noisy motor-drive systems. Its floating high-side driver uses a dedicated level shifter referenced to the HS node, supporting up to 100-V switch-node voltage with 110-V absolute max boot voltage.

UVLO is implemented separately on VDD (5.0-V typical rising threshold) and HB–HS (3.7-V typical rising threshold), ensuring safe startup and fault isolation. Interlock logic forces both HO and LO low when HI and LI are simultaneously high-preventing cross-conduction without adding fixed dead time or degrading propagation delay matching.

Key Specifications

Pinout & Package

VSON-10 package with exposed thermal pad; 3.00 mm × 3.00 mm body size; thermal pad must be connected to VSS ground plane for optimal thermal performance.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar half-bridge gate driver applications.

Compared with UCC27211DR and IRS2004STRPBF, LM5108DRCT uniquely combines integrated bootstrap diode, EN pin, 3-mm × 3-mm footprint, and 1-ns delay matching-making it optimal for compact, battery-operated, high-efficiency half-bridge systems where BOM reduction and timing precision are critical.

Availability

LM5108DRCT is available at Aetrix Electronics and suitable for motor drives, switch-mode power supplies, and auxiliary inverters requiring stable component supply, long-term lifecycle support, and consistent parametric performance across production batches.

Supply support for LM5108DRCT includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Texas Instruments is a global semiconductor leader specializing in analog, embedded processing, and power management technologies, with decades of expertise in high-reliability industrial and automotive-grade components.

The LM5108DRCT belongs to TI's high-voltage gate driver product line, engineered specifically for robust, compact half-bridge control in battery-powered power tools, high-frequency SMPS, and resonant converters demanding precise timing and shoot-through immunity.

FAQ

What is the maximum allowable voltage on the HS pin of the LM5108DRCT?

The LM5108DRCT specifies an absolute maximum HS voltage of 105 V DC and –7 V for negative transients (<100 ns). Its recommended operating range is –1 V to 100 V. Exceeding these limits risks permanent damage. The device's interlock logic and dual UVLO protect against overvoltage-induced shoot-through, but system-level clamping (e.g., Schottky diodes) is advised for transient suppression beyond spec.

Does the LM5108DRCT require an external bootstrap diode?

No, the LM5108DRCT integrates a bootstrap diode between VDD and HB pins, eliminating the need for an external discrete diode. This reduces BOM count and PCB area-critical in compact power tool designs. However, an external bootstrap capacitor (typically 0.1 µF) is still required between HB and HS pins to sustain high-side gate drive during continuous conduction.

How does the interlock feature of the LM5108DRCT prevent shoot-through?

The LM5108DRCT's interlock feature forces both HO and LO outputs low whenever HI and LI inputs are simultaneously high-regardless of pulse width or timing overlap. This hardware-level logic prevents concurrent high-side and low-side conduction without introducing fixed dead time or degrading propagation delay matching, preserving efficiency while enhancing system robustness in motor drive applications.

What is the purpose of the EN pin on the LM5108DRCT, and what happens when it is left floating?

The EN pin on the LM5108DRCT is an active-high enable input with a 250-kΩ internal pulldown resistor. When left floating or pulled low, the driver disables both HO and LO outputs and draws only 7 µA quiescent current. This enables ultra-low-power standby in battery-powered tools. For always-on operation, tie EN directly to VDD; for noise immunity, add a 1-nF capacitor from EN to VSS near the pin.

Can the LM5108DRCT drive silicon carbide (SiC) or gallium nitride (GaN) FETs?

Yes, the LM5108DRCT can drive SiC and GaN FETs in half-bridge configurations, provided gate charge requirements fall within its 2.6-A sink / 1.6-A source capability and voltage ratings (≤100 V HS, ≤110 V HB) are respected. Its 20-ns propagation delay and 1-ns delay matching support high-frequency switching, but external gate resistors may be needed to dampen ringing and control dV/dt-especially with fast-switching wide-bandgap devices.