Texas Instruments LM5101CSD/NOPB

Overview

LM5101CSD/NOPB from Texas Instruments is a 1-A, high-voltage dual gate driver IC designed to independently control high-side and low-side N-channel MOSFETs in synchronous buck and half-bridge power converters. It features TTL-compatible inputs, 118-V bootstrap supply capability, 26–56 ns propagation delay (typ), 8-ns rise/fall times into 1000-pF load, and integrated bootstrap diode - enabling compact, efficient high-frequency switching in isolated gate-drive topologies.

For engineers reviewing the LM5101CSD/NOPB datasheet, LM5101CSD/NOPB pinout, LM5101CSD/NOPB application, or LM5101CSD/NOPB equivalent, key selection criteria include its 1-A peak output current, TTL input threshold (1.3–2.3 V), HS node voltage tolerance up to 100 V, UVLO on both VDD and HB rails, and SO PowerPAD-8 package thermal performance (R_θJA = 40°C/W).

Technical Context

The LM5101CSD/NOPB implements a robust level-shifting architecture that references the high-side driver to the HS node, enabling clean, fast logic-to-HO transitions while maintaining tight propagation delay matching (≤10 ns) between LO and HO paths. Its integrated bootstrap diode (V_F = 0.8 V @ 100 mA, t_rr = 37 ns) eliminates external diode requirements and supports reliable boot capacitor recharge at high dV/dt (HS slew rate < 50 V/ns).

Undervoltage lockout operates independently on VDD (6.0–7.4 V rising threshold) and HB–HS (5.7–7.1 V), disabling only the affected output stage during fault conditions. The device operates across –40°C to +125°C junction temperature with TTL-input hysteresis of 50 mV, ensuring noise immunity in noisy power-converter environments.

Key Specifications

Pinout & Package

LM5101CSD/NOPB is housed in an 8-pin SO PowerPAD™ package (3.90 mm × 4.89 mm) with exposed thermal pad soldered to PCB ground plane for enhanced thermal dissipation (R_θJC(bot) = 4.4°C/W). The package is RoHS-compliant and lead-free (NOPB suffix).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-voltage dual gate driver applications.

Compared with LM5101ASD/NOPB, LM5101CSD/NOPB trades peak current for lower quiescent power and smaller gate drive loop area; versus UCC27201D, it offers superior thermal performance and integration but requires TTL-level controller outputs.

Availability

LM5101CSD/NOPB is available at Aetrix Electronics and suitable for synchronous buck converters, half-bridge power supplies, and two-switch forward converters requiring stable component supply, long-term industrial lifecycle support, and RoHS-compliant packaging.

Supply support for LM5101CSD/NOPB 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 power conversion ICs.

The LM5100/LM5101 family was developed to address the need for integrated, high-voltage dual gate drivers in space-constrained, high-efficiency DC/DC converters - emphasizing bootstrap integration, thermal robustness, and precise timing control for Si and SiC power stages.

FAQ

What is the maximum allowable voltage on the HS pin of the LM5101CSD/NOPB?

The LM5101CSD/NOPB specifies a maximum HS-to-VSS voltage of 100 V under recommended operating conditions. Absolute maximum rating allows transient excursions up to 100 V, with negative transients limited to VDD – 15 V. This rating enables use with 48-V, 60-V, and 100-V bus systems in half-bridge and synchronous buck topologies. Always verify HS node clamping in application with external MOSFET body diode or snubber.

Does the LM5101CSD/NOPB require an external bootstrap diode?

No, the LM5101CSD/NOPB integrates a high-voltage bootstrap diode (anode to VDD, cathode to HB) with 118-V reverse rating, 0.8-V forward drop at 100 mA, and 37-ns reverse recovery time. This eliminates the need for an external diode, reducing component count, PCB area, and parasitic inductance in the bootstrap path - directly improving reliability and switching performance in high-dV/dt applications.

What is the input logic compatibility of the LM5101CSD/NOPB?

The LM5101CSD/NOPB features TTL-compatible inputs: HI and LI accept 0–VDD logic signals with V_IL = 1.3–2.3 V (max) and V_IH = 2.0–3.0 V (min) at 25°C, and 50-mV hysteresis for noise immunity. This allows direct interface with 3.3-V and 5-V microcontrollers, DSPs, and PWM controllers without level-shifting circuitry - simplifying system design and reducing BOM cost.

How does the UVLO function on the LM5101CSD/NOPB protect the power stage?

The LM5101CSD/NOPB implements independent undervoltage lockout on both VDD (6.0–7.4 V rising threshold) and HB–HS (5.7–7.1 V) rails. If VDD falls below threshold, both LO and HO are forced low. If HB–HS drops below its threshold, only HO is disabled - preserving low-side control during bootstrap faults. Hysteresis (0.4–0.5 V) prevents oscillation during marginal supply conditions, safeguarding MOSFETs from partial turn-on and shoot-through.

What thermal performance can be expected from the LM5101CSD/NOPB in SO PowerPAD-8 package?

In the SO PowerPAD-8 package, the LM5101CSD/NOPB achieves R_θJA = 40°C/W on a standard 4-layer PCB with 50-mm × 50-mm ground/power planes and exposed pad soldered to copper. This enables continuous 1-A gate drive at 125°C junction temperature with ≤15°C rise above ambient - eliminating need for heatsinks in most industrial and telecom power supply designs. R_θJC(bot) = 4.4°C/W confirms efficient heat transfer to PCB.