Texas Instruments LM285LPRE3-1-2

Overview

LM285LPRE3-1-2 from Texas Instruments is a micropower, two-terminal, band-gap voltage reference in TO-92 package, delivering 1.235 V nominal output with ±20 ppm/°C temperature coefficient, 10 μA to 20 mA operating current range, and 1.5 Ω max reference impedance over full temperature range. It serves as a precision shunt reference in battery-powered analog signal conditioning and portable instrumentation.

For engineers reviewing the LM285LPRE3-1-2 datasheet, LM285LPRE3-1-2 pinout, LM285LPRE3-1-2 application, or LM285LPRE3-1-2 equivalent, key selection criteria include initial voltage tolerance (1.223–1.247 V at 25°C), long-term stability (±20 ppm/khr), low-noise operation (60 µV broadband), and compatibility with capacitive loads up to 10 µF without instability.

Technical Context

The LM285LPRE3-1-2 implements a floating shunt topology using band-gap core with on-chip trimming for tight initial accuracy. Its internal high-gain amplifier and shunt pass element regulate cathode-to-anode voltage by sinking current proportional to error, requiring only a minimum 10 µA cathode current for regulation.

It features internal frequency compensation enabling stable operation with any capacitive load, including bypass capacitors up to 10 µF. The device operates across –40°C to +85°C and exhibits low dynamic impedance (≤1.5 Ω) and low broadband noise (60 µV, 10 Hz–10 kHz), making it suitable for high-precision, low-power analog references where supply headroom is constrained.

Key Specifications

Pinout & Package

LM285LPRE3-1-2 uses TO-92 (LP) package: 3-pin, through-hole, straight or formed leads, 4.30 mm × 4.30 mm body, 5.34 mm max height, Pb-Free (RoHS) Sn finish, no MSL rating (non-moisture-sensitive).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar shunt voltage reference applications.

Compared with LM385LPRE3-1-2 and TLVH431ACLP, the LM285LPRE3-1-2 uniquely combines –40°C to +85°C operation, 10 µA minimum current, and true two-terminal simplicity-making it the optimal choice for ruggedized portable instrumentation where reliability and minimal bill-of-materials are prioritized.

Availability

LM285LPRE3-1-2 is available at Aetrix Electronics and suitable for portable meter references, battery-operated systems, and current-loop instrumentation requiring stable component supply with guaranteed long-term continuity.

Supply support for LM285LPRE3-1-2 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 company specializing in analog and embedded processing technologies, with leadership in precision analog ICs and power management solutions.

The LMx85-1.2 family was designed specifically for micropower, high-stability shunt voltage references in portable and battery-constrained applications-emphasizing low drift, capacitive-load tolerance, and wide operating current range.

FAQ

What is the minimum cathode current required for regulation in LM285LPRE3-1-2?

The LM285LPRE3-1-2 requires a minimum cathode current of 10 µA to achieve proper regulation and specified voltage accuracy. Below this threshold, output voltage deviates significantly from 1.235 V, and temperature coefficient degrades. This value is confirmed in Section 7.5 Electrical Characteristics of the SLVS075J datasheet under "Minimum reference current" for LM285-1.2. Operating the LM285LPRE3-1-2 at 10 µA enables multi-year battery life in coin-cell applications.

Can LM285LPRE3-1-2 be used with large bypass capacitors?

Yes, the LM285LPRE3-1-2 is explicitly designed for capacitive-load immunity and remains stable with ceramic bypass capacitors up to 10 µF on the cathode node. Its internal frequency compensation eliminates the need for series isolation resistors or external phase compensation networks. This capability is documented in the "Feature Description" (Section 8.3) and "Layout Guidelines" (Section 11.1) of the SLVS075J datasheet, confirming robustness in noisy portable environments where large decoupling is standard practice.

What is the operating temperature range of LM285LPRE3-1-2?

The LM285LPRE3-1-2 is rated for operation from –40°C to +85°C, as specified in the "Recommended Operating Conditions" table (Section 7.3) of the SLVS075J datasheet. This extended industrial temperature range distinguishes it from the LM385-1.2 and LM385B-1.2 variants, which are limited to 0°C to +70°C. The full-range specification makes the LM285LPRE3-1-2 suitable for outdoor instrumentation, automotive cabin sensors, and industrial handheld tools exposed to ambient extremes.

Does LM285LPRE3-1-2 have a specified long-term stability parameter?

Yes, the LM285LPRE3-1-2 has a long-term stability specification of ±20 ppm per kilohour (ppm/khr) at 25°C and 100 µA cathode current, as listed in Section 7.5 Electrical Characteristics under "Long-term change in reference voltage". This translates to less than 0.2% total drift over 10 years of continuous operation-critical for maintenance-free portable equipment such as utility-grade energy meters and environmental data loggers where field recalibration is impractical.

Is LM285LPRE3-1-2 RoHS compliant and lead-free?

Yes, the LM285LPRE3-1-2 is Pb-Free (RoHS compliant) with Sn (tin) lead finish, as confirmed in the Package Option Addendum (Page 1) of the SLVS075J datasheet. Its eco plan is marked "Pb-Free (RoHS)", and it carries no MSL rating due to its TO-92 (LP) package construction. This compliance meets global environmental regulations for consumer, industrial, and medical electronics, and supports lead-free reflow soldering processes without requiring special handling or exemptions.