Texas Instruments LM285LPE3-1-2

Overview

LM285LPE3-1-2 from Texas Instruments is a micropower, two-terminal, band-gap voltage reference optimized for battery-operated systems requiring 1.235 V ±1% initial tolerance, 10 μA to 20 mA operating current, and ±20 ppm/°C temperature coefficient over −40°C to +85°C. It delivers low dynamic impedance (1.5 Ω max), 60 µV broadband noise, and stable regulation under capacitive loading - enabling precision analog sensing in portable test instruments.

For engineers reviewing the LM285LPE3-1-2 datasheet, LM285LPE3-1-2 pinout, LM285LPE3-1-2 application, or LM285LPE3-1-2 equivalent, key selection criteria include its TO-92 package compatibility with legacy shunt reference layouts, guaranteed operation down to 10 µA cathode current, and tight initial voltage tolerance without external trimming.

Technical Context

The LM285LPE3-1-2 implements a floating shunt topology with on-chip band-gap core and high-gain amplifier driving a pass element, enabling stable voltage regulation across wide current and temperature ranges. Its internal frequency compensation ensures stability with any capacitor load, eliminating need for external phase compensation.

This device operates exclusively in fixed-voltage reference mode with no adjustability; regulation initiates only when cathode current exceeds 10 µA, and it maintains output accuracy via laser-trimmed resistor networks that set both nominal voltage and temperature coefficient.

Key Specifications

Pinout & Package

LM285LPE3-1-2 uses the TO-92 (LP) package: 3-pin, through-hole, straight or formed leads, 5.34 mm max height, body size 4.30 mm × 4.30 mm. Pin 1 = Anode, Pin 2 = Cathode, Pin 3 = No internal connection (NC).

Key Features

Applications

Equivalent & Alternatives

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

Compared with LM385BLPE3-1-2, LM285LPE3-1-2 provides wider temperature range and tighter initial tolerance at identical package and pinout; versus TLVH431ACLP, it offers lower minimum current and simpler 2-terminal integration but lacks adjustability and ultra-low impedance.

Availability

LM285LPE3-1-2 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 LM285LPE3-1-2 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 - prioritizing low quiescent current, wide temperature operation, and robust capacitive-load immunity.

FAQ

What is the minimum cathode current required for regulation in the LM285LPE3-1-2?

The LM285LPE3-1-2 requires a minimum cathode current of 10 µA to establish and maintain regulation at its nominal 1.235 V output. Below this threshold, the device enters non-regulated state and output voltage drops nonlinearly. This value is specified across the full −40°C to +85°C operating temperature range and is critical for low-power sleep-mode design in battery-operated systems using the LM285LPE3-1-2.

Does the LM285LPE3-1-2 require external capacitors for stability?

No, the LM285LPE3-1-2 does not require external capacitors for stability. Its internal frequency compensation ensures unconditional stability with any capacitive load on the cathode pin - including large bulk decoupling caps or long PCB traces. This eliminates risk of oscillation and simplifies layout, making the LM285LPE3-1-2 ideal for space-constrained portable designs where board area is at premium.

What is the temperature coefficient specification for the LM285LPE3-1-2?

The LM285LPE3-1-2 has an average temperature coefficient of ±20 ppm/°C over its full operating range of −40°C to +85°C. This means the reference voltage drift is bounded to approximately ±0.5 mV across the entire temperature span, enabling high-accuracy measurements in uncontrolled environments. The value is measured as total change in reference voltage divided by the temperature range, per TI's SLVS075J datasheet specification for the LM285LPE3-1-2.

Can the LM285LPE3-1-2 be used in series with other references or regulators?

The LM285LPE3-1-2 is a two-terminal shunt reference and must be connected between cathode (output) and anode (ground). It cannot be placed in series with other references or regulators because it lacks a dedicated input pin and relies on externally sourced cathode current. Attempting series connection violates its floating shunt architecture and will prevent proper regulation. For stacked references, discrete Zener diodes or series-adjustable regulators like TLVH431 are appropriate alternatives to the LM285LPE3-1-2.

Is the LM285LPE3-1-2 RoHS compliant and lead-free?

Yes, the LM285LPE3-1-2 is Pb-Free (RoHS compliant) with Sn (tin) lead finish, as confirmed in TI's official packaging addendum. It meets EU RoHS requirements for all 10 restricted substances, including ≤0.1% by weight for lead in homogeneous materials. The "E3" suffix explicitly denotes the RoHS-compliant, lead-free variant in TI's TO-92 LP package offering, distinguishing it from legacy leaded versions such as LM285LP-1-2.