Analog Devices Inc. LT1034IZ-1.2#TRPBF

Overview

LT1034IZ-1.2#TRPBF from Analog Devices (formerly Linear Technology) is a micropower, precision dual-output voltage reference IC providing a 1.225V bandgap output and a 7.0V subsurface zener output in a 3-lead TO-92 plastic package. It delivers 20 ppm/°C max temperature drift (industrial grade), 1Ω typical reverse dynamic impedance, 20µA minimum operating current, and ±1.2mV reverse breakdown change over 100µA–2mA for the 1.2V output - used in portable meters and precision regulators requiring stable low-power biasing.

For engineers reviewing the LT1034IZ-1.2#TRPBF datasheet, LT1034IZ-1.2#TRPBF pinout, LT1034IZ-1.2#TRPBF application, or LT1034IZ-1.2#TRPBF equivalent, key selection criteria include guaranteed industrial-temperature drift performance, dual-reference architecture with independent 1.2V/7V outputs, low quiescent current operation, and TO-92 compatibility for space-constrained analog signal chains.

Technical Context

The LT1034IZ-1.2#TRPBF integrates two physically separate reference elements: a laser-trimmed thin-film bandgap cell for the 1.225V output and a subsurface zener diode for the 7.0V output. Both operate in reverse-biased mode, with the 1.2V section specified for 20µA–2mA current range and the 7V section rated at 100µA nominal.

Its internal architecture avoids interaction between outputs under normal biasing - forward-biasing either terminal degrades the other's regulation, per datasheet Note 2. The device supports industrial temperature range (–40°C to +85°C) and achieves <6µV_P-P low-frequency noise (0.1Hz–10Hz) at 100µA.

Key Specifications

Pinout & Package

LT1034IZ-1.2#TRPBF uses the Z package: 3-lead TO-92 plastic case with standard lead configuration (flat side facing viewer, leads down). Pin 1 = 1.2V output, Pin 2 = GND, Pin 3 = 7V output. No NC pins. Thermal resistance θ_JA = 160°C/W.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual-output voltage reference applications.

Compared with LT1034IZ-1.2#TRPBF, LT1004CZ-1.2 offers lower cost but sacrifices dual-output capability and industrial-tempco guarantee, while REF191GS improves precision and stability at the expense of power efficiency and mechanical compatibility with legacy TO-92 layouts.

Availability

LT1034IZ-1.2#TRPBF is available at Aetrix Electronics and suitable for portable meters, precision regulators, and calibrators requiring stable component supply with guaranteed industrial-temperature performance and TO-92 mechanical compatibility.

Supply support for LT1034IZ-1.2#TRPBF 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 its precision analog portfolio, including voltage references, op-amps, and data converters, with focus on high-reliability industrial and instrumentation markets.

The LT1034IZ-1.2#TRPBF belongs to Linear's legacy micropower reference family designed specifically for battery-operated test equipment and portable instrumentation requiring dual-voltage biasing with guaranteed temperature stability.

FAQ

What is the maximum operating temperature range for the LT1034IZ-1.2#TRPBF?

The LT1034IZ-1.2#TRPBF is rated for industrial temperature operation from –40°C to +85°C. This range is guaranteed for all electrical specifications including 20 ppm/°C max temperature coefficient and 1.225V ±1% output voltage. The "I" suffix in the part number explicitly denotes industrial-grade qualification, distinct from commercial-grade (C) or military-grade (M) variants.

Can the 7V output of the LT1034IZ-1.2#TRPBF be used simultaneously with the 1.2V output?

Yes, the LT1034IZ-1.2#TRPBF is designed for concurrent use of both outputs: Pin 1 (1.2V) and Pin 3 (7V) operate independently under reverse bias. However, datasheet Note 2 warns that forward-biasing either terminal disrupts regulation of the other - so both must remain reverse-biased during normal operation. Load currents must stay within specified ranges (100µA–2mA for 1.2V; 100µA nominal for 7V).

Is the LT1034IZ-1.2#TRPBF pin-compatible with the LM385Z-1.2?

No, the LT1034IZ-1.2#TRPBF is not pin-compatible with LM385Z-1.2. While both use TO-92 packages, LM385Z-1.2 has Pin 1 = Cathode (1.2V), Pin 2 = Anode (GND), whereas LT1034IZ-1.2#TRPBF uses Pin 1 = 1.2V output, Pin 2 = GND, Pin 3 = 7V output. Using LT1034IZ-1.2#TRPBF in an LM385Z-1.2 layout would short the 7V output to ground unless the PCB is modified.

What is the minimum current required to maintain regulation on the 1.2V output of the LT1034IZ-1.2#TRPBF?

The LT1034IZ-1.2#TRPBF requires a minimum reverse current of 20µA on the 1.2V output (Pin 1) to maintain regulation and specified accuracy. Below this threshold, output voltage deviates significantly from 1.225V and temperature coefficient degrades. This value is guaranteed for the "I" grade and appears in the Electrical Characteristics table under "Minimum Operating Current" for LT1034-1.2.

Does the LT1034IZ-1.2#TRPBF require external capacitors for stability?

The LT1034IZ-1.2#TRPBF does not require external capacitors for basic regulation stability, but a 100nF ceramic capacitor is recommended between Pin 1 (1.2V) and Pin 2 (GND) to suppress high-frequency noise and improve PSRR. The 7V output (Pin 3) benefits from a 1µF tantalum or aluminum electrolytic capacitor to dampen zener-related ripple, especially when driving dynamic loads like relay coils.