Analog Devices Inc. LT3055IDE-5#PBF

Overview

LT3055IDE-5#PBF from Analog Devices is a 500mA, low-dropout linear regulator with fixed 5V output, ±45V input rating, precision programmable current limit (±10%), and integrated diagnostics including dual FAULT pins, PWRGD, TEMP, and IMON current monitor (1/500× I_OUT). It delivers stable 5V power for automotive telematics and industrial control systems requiring robust fault detection and reverse protection.

For engineers reviewing the LT3055IDE-5#PBF datasheet, LT3055IDE-5#PBF pinout, LT3055IDE-5#PBF application, or LT3055IDE-5#PBF equivalent, this page provides verified specifications including dropout voltage (350mV @ 500mA), output noise (25μV_RMS, 10Hz–100kHz), temperature monitoring (10mV/°C), and diagnostic logic behavior under current-limit, thermal-limit, and open-circuit conditions.

Technical Context

The LT3055IDE-5#PBF implements a micropower LDO architecture with internal PMOS pass device, precision bandgap reference, and analog diagnostic comparators. Its dual FAULT pins provide independent assertion for minimum output current (FAULT1) and overcurrent/thermal events (FAULT2), enabling discrete fault classification without microcontroller intervention.

Current limiting is externally programmable via resistor to IMAX pin (e.g., 604Ω sets 497mA limit), while minimum load detection uses IMIN pin with resistor-to-GND (e.g., 120kΩ sets 10mA threshold). The TEMP pin outputs 250mV at 25°C with 10mV/°C slope, calibrated for average die temperature-not junction peak.

Key Specifications

Pinout & Package

LT3055IDE-5#PBF is housed in a 16-lead (4mm × 3mm) plastic DFN package with exposed GND pad (Pin 17) requiring PCB soldering for thermal and electrical integrity. Thermal resistance θ_JA = 38°C/W, θ_JC = 4.3°C/W.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LT3055EMSE-5#PBF, the LT3055IDE-5#PBF offers superior thermal performance (θ_JA = 38°C/W vs. 37°C/W is comparable, but DFN's exposed pad improves θ_JC to 4.3°C/W vs. 5°C/W) and smaller footprint; versus TPS7A4701RGWR, it trades 5μV_RMS noise reduction for comprehensive fault visibility, programmable current limiting, and die temperature telemetry - critical for functional safety compliance.

Availability

LT3055IDE-5#PBF is available at Aetrix Electronics and suitable for automotive telematics, industrial control systems, and noise-sensitive RF supplies requiring stable component supply with full traceability and long-term lifecycle support.

Supply support for LT3055IDE-5#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, Inc. is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, serving industrial, automotive, communications, and healthcare markets.

The LT3055IDE-5#PBF belongs to the LT3055 series of micropower LDO regulators designed for high-reliability applications demanding precision current limiting, comprehensive diagnostics, and robust protection in harsh electrical environments.

FAQ

What is the maximum input voltage rating for the LT3055IDE-5#PBF?

The LT3055IDE-5#PBF has an absolute maximum input voltage rating of ±50V on the IN pin, with a functional input range of 1.6V to 45V. This ±45V rating enables operation in automotive environments subject to load-dump transients and reverse-battery conditions without external protection circuitry - a key design advantage of the LT3055IDE-5#PBF.

How does the FAULT1 and FAULT2 pin behavior differ in the LT3055IDE-5#PBF?

In the LT3055IDE-5#PBF, FAULT1 asserts low when output current falls below the IMIN-programmed threshold (e.g., open-circuit condition), while FAULT2 asserts low during current-limit activation or thermal shutdown. Both pins are open-collector and require external pull-ups; simultaneous low assertion on both pins specifically indicates thermal shutdown - a distinct diagnostic state not conflated with overcurrent in the LT3055IDE-5#PBF.

Can the LT3055IDE-5#PBF operate with ceramic output capacitors only?

Yes, the LT3055IDE-5#PBF is optimized for stability with low-ESR ceramic capacitors and requires only a minimum 3.3μF output capacitance. Unlike older LDOs, it imposes no ESR range requirement, eliminating the need for tantalum or aluminum electrolytic capacitors - simplifying design and improving reliability in the LT3055IDE-5#PBF implementation.

What is the accuracy and temperature coefficient of the TEMP pin in the LT3055IDE-5#PBF?

The TEMP pin of the LT3055IDE-5#PBF outputs 250mV at 25°C with a nominal slope of 10mV/°C and a total error of ±0.08V over –40°C to 125°C. This corresponds to ±8°C absolute accuracy, making it suitable for coarse thermal trend monitoring but not for precision junction temperature measurement - a defined specification of the LT3055IDE-5#PBF.

How is the precision current limit set for the LT3055IDE-5#PBF, and what tolerance does it achieve?

The precision current limit of the LT3055IDE-5#PBF is set by connecting a resistor between the IMAX pin and GND; for example, a 604Ω resistor programs a 497mA limit. This achieves ±10% accuracy over the full –40°C to 125°C temperature range and wide input voltage conditions - a guaranteed performance parameter documented for the LT3055IDE-5#PBF in its datasheet.