Analog Devices Inc. LT1076IT#PBF

Overview

LT1076IT#PBF from Analog Devices (formerly Linear Technology) is a 2A monolithic bipolar step-down switching regulator in a 5-lead TO-220 package, operating from 8V to 60V input with 100kHz fixed-frequency switching, 2.6A programmable current limit, and 8.5mA quiescent current. It implements classic buck topology with analog multiplier feedback for line-regulation independence and improved dynamic response in industrial power supplies.

For engineers reviewing the LT1076IT#PBF datasheet, LT1076IT#PBF pinout, LT1076IT#PBF application, or LT1076IT#PBF equivalent, key selection considerations include its 2A integrated switch rating, 100kHz switching frequency, 2.5V to 50V adjustable output range, thermal resistance of 4°C/W (junction-to-case), and compatibility with tapped-inductor and inverting configurations.

Technical Context

The LT1076IT#PBF uses a true analog multiplier in the feedback loop, making loop gain independent of input voltage and enabling near-instantaneous response to line transients. Its Darlington NPN switch (single NPN for LT1076 variant) supports VSW swing 40V below ground, enabling positive-to-negative and negative-boost topologies.

On-chip pulse-by-pulse current limiting provides robust overload protection, while frequency shifting down to 20kHz at low FB voltage ensures stable short-circuit current control. Micropower shutdown reduces supply current to 140–300µA, and the ILIM pin allows external adjustment of current limit down to zero in 7-pin variants - though the 5-pin LT1076IT#PBF fixes limit at 2.6A.

Key Specifications

Pinout & Package

LT1076IT#PBF is housed in a 5-lead plastic TO-220 package (T package) with tab connected to GND. The case serves as thermal and electrical ground reference, requiring direct soldering to copper pour for thermal performance.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar buck regulator applications.

Compared with LTC3632EMSE#PBF and LM2678SX-5.0/NOPB, LT1076IT#PBF uniquely supports inverting and tapped-inductor configurations due to its −40V VSW swing, retains analog multiplier-based line regulation for superior transient response, and operates up to 60V input - making it irreplaceable in high-input, multi-topology industrial power designs.

Availability

LT1076IT#PBF is available at Aetrix Electronics and suitable for industrial DC-DC power supplies, programmable lab power supplies, and positive-to-negative converters requiring stable component supply, long-term lifecycle support, and proven reliability in harsh environments.

Supply support for LT1076IT#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 support for legacy Linear products including the LT1076 family. Linear was renowned for precision analog and power management ICs with exceptional ruggedness and application-specific innovation.

The LT1076IT#PBF belongs to Linear's monolithic switching regulator product line, designed specifically for industrial and telecom power systems demanding wide input range, topology flexibility, and robust fault handling without external complexity.

FAQ

What is the maximum input voltage rating for LT1076IT#PBF?

The absolute maximum input voltage for LT1076IT#PBF is 60V. Operation is specified from 8V to 60V in buck mode, with self-boot capability enabling startup from as low as 5V in inverting or boost configurations. Exceeding 60V risks permanent damage per Absolute Maximum Ratings.

Can LT1076IT#PBF be used in a negative-output configuration?

Yes, LT1076IT#PBF supports positive-to-negative converter topologies because its VSW pin is rated to swing 40V below ground. This allows the switch node to drive the center tap of an inductor or cathode of a diode in inverting buck-boost arrangements, enabling clean –5V or –12V generation from a single positive input.

Is the current limit adjustable on LT1076IT#PBF?

No - the LT1076IT#PBF is a 5-lead TO-220 variant with fixed current limit of 2.6A (typical) when the ILIM pin is left open. Adjustable current limiting requires the 7-pin T7 package (e.g., LT1076IT7#PBF), which provides dedicated ILIM and SHDN pins for external resistor programming.

What is the thermal resistance of LT1076IT#PBF and how does it affect heatsinking?

LT1076IT#PBF has θ_JC = 4°C/W and θ_JA = 30°C/W (with 0.5 in² copper). At 2A output into 5V, dissipation is ~1.5W; with 4°C/W θ_JC, junction-to-case rise is ~6°C - meaning minimal heatsink is needed if the TO-220 tab is soldered to ≥1 oz. copper area. For ambient >70°C, derating applies per Industrial temperature range (–40°C to 85°C).

Does LT1076IT#PBF include built-in protection features?

Yes, LT1076IT#PBF integrates pulse-by-pulse current limiting (response <600ns), thermal shutdown (junction >125°C), micropower shutdown (140–300µA), and frequency shifting under overload. It lacks hiccup-mode or auto-restart, relying instead on continuous current limiting and controlled frequency reduction to sustain safe operation during sustained faults.