Analog Devices Inc. LT1158IN#PBF

Overview

LT1158IN#PBF from Analog Devices (formerly Linear Technology) is a half-bridge N-channel power MOSFET driver IC designed to synchronously control two external N-channel MOSFETs in totem-pole configuration. It features adaptive non-overlap gate drives, 150 ns transition times driving 3000 pF, over 500 mA peak output current, and integrated charge pump for DC-capable top-side drive. It is used in synchronous step-down switching regulators and motor control systems requiring shoot-through protection and current-limited operation.

For engineers reviewing the LT1158IN#PBF datasheet, LT1158IN#PBF pinout, LT1158IN#PBF application, or LT1158IN#PBF equivalent, key selection considerations include its –40°C to +85°C industrial temperature range, 16-lead plastic DIP package, adaptive shoot-through prevention, continuous current limit loop with 110 mV fault conduction threshold, and compatibility with logic-level and standard N-channel MOSFETs.

Technical Context

The LT1158IN#PBF implements dual independent gate drivers with separate feedback and drive pins per side-T GATE DR/T GATE FB for top-side and B GATE DR/B GATE FB for bottom-side-enabling precise V_GS monitoring and DC sustaining current delivery. Its internal charge pump activates during DC or high-duty-cycle operation to maintain top-side gate voltage above V+, while adaptive timing prevents simultaneous conduction by enforcing turn-off-before-turn-on sequencing based on actual gate discharge thresholds (1.75 V for top, 1.5 V for bottom).

It integrates a current-sense comparator with Kelvin-connected SENSE+ and SENSE– inputs referenced to the floating top-source node (Pin 13), enabling accurate short-circuit detection at 110 mV nominal fault threshold and closed-loop current limiting at 120–180 mV. The FAULT open-collector output supports automatic shutdown-and-retry via enable-loop feedback, and the 25 μA internal pull-up on ENABLE (Pin 4) enables self-enabling operation.

Key Specifications

Pinout & Package

LT1158IN#PBF is housed in a 16-lead plastic DIP (N package) with θ_JA = 70°C/W, rated for –40°C to +85°C operation. Pin functions are electrically isolated between top- and bottom-side sections to support floating high-side drive.

Key Features

Applications

Equivalent & Alternatives

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

Compared with IRS21844PbF and LM5109BMM/NOPB, the LT1158IN#PBF uniquely combines adaptive shoot-through prevention, integrated current-sense protection, and charge-pump-enabled DC operation - making it optimal for industrial motor control and high-efficiency synchronous buck designs where reliability and protection integrity are critical.

Availability

LT1158IN#PBF is available at Aetrix Electronics and suitable for synchronous buck regulators, BLDC motor drives, and high-current transducer drivers requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for LT1158IN#PBF 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

Analog Devices acquired Linear Technology in 2017 and maintains full product support, documentation, and manufacturing continuity for legacy Linear parts including the LT1158 family.

The LT1158 product line was engineered specifically for high-reliability half-bridge gate driving in switching power supplies and motor control, emphasizing adaptive timing, integrated protection, and robust operation across wide supply and temperature ranges.

FAQ

What is the maximum operating supply voltage for the LT1158IN#PBF?

The LT1158IN#PBF has an absolute maximum supply voltage rating of 36 V on Pins 2 and 10. It operates continuously over 5 V to 30 V, with internal bias regulation ensuring stable performance across this range. Exceeding 36 V risks permanent damage; for 30 V nominal systems, ensure transient spikes remain below this limit using appropriate input filtering. The LT1158IN#PBF's robust 36 V rating supports 24 V industrial bus applications with margin.

How does the LT1158IN#PBF prevent shoot-through in half-bridge configurations?

The LT1158IN#PBF prevents shoot-through using adaptive non-overlap timing: it monitors actual gate discharge via T GATE FB (Pin 14) and B GATE FB (Pin 8), enforcing turn-off completion (V_GS < 1.75 V for top, <1.5 V for bottom) before enabling the opposing MOSFET. This eliminates reliance on fixed dead-time or matched MOSFETs. The LT1158IN#PBF achieves this without external components, reducing design complexity and improving reliability across temperature and process variation.

Can the LT1158IN#PBF drive logic-level MOSFETs from a 5 V supply?

Yes, the LT1158IN#PBF supports 5 V operation and is compatible with logic-level N-channel MOSFETs (e.g., V_GS(th) ≤ 2 V). Its gate drive outputs deliver >500 mA peak and clamp V_GS to 14.5 V, preventing overdrive of 8 V-rated devices. At 5 V supply, the internal charge pump boosts top-gate voltage sufficiently for full enhancement. The LT1158IN#PBF maintains 150 ns transition times even at minimum 4.5 V supply, ensuring consistent performance in battery-powered systems.

What is the role of the SENSE+ and SENSE– pins on the LT1158IN#PBF?

SENSE+ (Pin 12) and SENSE– (Pin 11) form a Kelvin-connected differential input for the integrated current-sense comparator. They measure voltage across a shunt resistor (or sense-FET) in the top MOSFET source path to detect overcurrent. The LT1158IN#PBF triggers FAULT (Pin 5) when V_SENSE+ – V_SENSE– exceeds 110 mV and regulates current at 120–180 mV in closed loop. This enables accurate, ground-referenced current limiting without adding measurement error from PCB trace resistance.

Does the LT1158IN#PBF require external components for bootstrap operation?

Yes, the LT1158IN#PBF requires an external bootstrap diode (e.g., BAT85) and capacitor (typically 0.1 μF) between BOOST (Pin 16) and T SOURCE (Pin 13). The internal BOOST DR (Pin 1) actively recharges the capacitor to 14.5 V above T SOURCE during PWM off-time. For DC or high-duty-cycle operation, the on-chip charge pump sustains top-gate voltage - but the external bootstrap network remains essential for initial startup and transient recovery. The LT1158IN#PBF's design minimizes external part count while maintaining robustness.