Texas Instruments LT1004ID-1-2

Overview

LT1004ID-1-2 from Texas Instruments is a two-terminal micropower band-gap voltage reference IC delivering 1.235 V nominal output with ±4 mV initial accuracy, 20 ppm/°C temperature coefficient, and 0.6 Ω reference impedance at 100 µA-designed for precision low-power applications such as portable test instruments and battery-operated systems.

For engineers reviewing the LT1004ID-1-2 datasheet, LT1004ID-1-2 pinout, LT1004ID-1-2 application, or LT1004ID-1-2 equivalent, key selection criteria include its guaranteed operation from −40°C to 85°C, ultra-low 8–12 µA minimum reference current, and compatibility with current-loop instrumentation requiring stable 1.2 V references under microampere bias conditions.

Technical Context

The LT1004ID-1-2 implements a band-gap reference architecture optimized for micropower operation, achieving high accuracy without external trimming by tightly controlling process parameters and on-die component matching. Its two-terminal configuration simplifies integration into floating or grounded reference paths.

It operates over a reverse current range of 8 µA to 20 mA, maintains sub-1.5 mV reference voltage change across full temperature range (−40°C to 85°C), and exhibits low broadband noise (60–120 µV RMS, 10 Hz–10 kHz) critical for high-resolution ADC biasing and sensor signal conditioning.

Key Specifications

Pinout & Package

LT1004ID-1-2 is housed in an 8-pin SOIC (D package) with internal connections per TI's LP/D-package pinout: Pins 1–3 and 6–8 are NC (no internal connection); Pin 4 is Anode; Pin 5 is Cathode. Terminals 6 and 8 are internally connected but not bonded to die.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LT1004ID-1-2, LM385B-1.2 offers lower cost but sacrifices 3× initial accuracy and 5× temperature stability, while REF101CP provides better accuracy than LM385 but demands higher bias current and lacks SOIC compatibility-making LT1004ID-1-2 optimal for new industrial-grade portable designs requiring precision, low power, and surface-mount integration.

Availability

LT1004ID-1-2 is available at Aetrix Electronics and suitable for portable test instruments, battery-operated systems, and current-loop instrumentation requiring stable component supply with guaranteed long-term availability and traceable sourcing.

Supply support for LT1004ID-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 leader specializing in analog, embedded processing, and digital signal technologies, with decades of leadership in precision analog ICs.

The LT1004 series was designed specifically for micropower, high-accuracy voltage reference applications in portable, battery-constrained, and industrial measurement systems-emphasizing low drift, minimal trim requirements, and robust temperature performance.

FAQ

What is the operating temperature range for LT1004ID-1-2?

The LT1004ID-1-2 is characterized for operation from −40°C to +85°C, meeting industrial-grade environmental requirements. This rating is confirmed in the ordering information table and absolute maximum ratings section of the SLVS022M datasheet, where "LT1004I" suffix denotes the extended temperature grade. The device maintains specified electrical performance-including ±4 mV initial accuracy and 20 ppm/°C tempco-across this full range.

Is LT1004ID-1-2 pin-compatible with LM285-1.2?

Yes, LT1004ID-1-2 is explicitly documented as a pin-for-pin replacement for the LM285 and LM385 series. The datasheet states: "The LT1004 is a pin-for-pin replacement for the LM285 and LM385 series of references, with improved specifications." Both devices use identical SOIC-8 (D package) footprints and share the same anode/cathode terminal locations (Pins 4 and 5), enabling direct substitution without layout modification.

What is the minimum reference current required for LT1004ID-1-2 to regulate properly?

The LT1004ID-1-2 requires a minimum reference current of 8 µA to maintain regulation, as specified in the "Electrical Characteristics" table under I_Z(min) for the LT1004I grade. This value is validated across the full −40°C to +85°C temperature range and enables reliable startup from ultra-low-current sources such as the LM334 or thermocouple compensation circuits.

Does LT1004ID-1-2 require an output capacitor for stability?

No, LT1004ID-1-2 does not require an external output capacitor for stability. As a two-terminal band-gap reference, it is internally compensated and remains stable under all specified operating conditions-including capacitive loads up to 10 nF-as confirmed by transient response waveforms (Figures 8 and 15) and application circuits (e.g., Figure 20: "Micropower Reference From 9-V Battery") in the SLVS022M datasheet.

How does the reference impedance of LT1004ID-1-2 affect load regulation?

The LT1004ID-1-2 exhibits a typical reference impedance of 0.6 Ω at 100 µA, which directly determines load regulation error: a 1 mA load variation causes ≤0.6 mV output shift. This low impedance ensures high accuracy in buffered configurations (e.g., op-amp followers) and minimizes error in current-source topologies where the reference sets voltage across a precision resistor-critical for 4–20 mA loop accuracy.