Allegro MicroSystems A1366LKTTG-5-T

Overview

The A1366LKTTG-5-T from Allegro MicroSystems is a factory-programmed linear Hall-effect current sensor IC designed for high-accuracy, high-bandwidth analog current sensing in automotive power systems. It delivers 5 mV/G sensitivity, ±0.25% linearity error, 120 kHz bandwidth, and flat temperature performance from –40°C to 150°C - enabling precise closed-loop control in HEV inverters and electric power steering (EPS) systems.

For engineers reviewing the A1366LKTTG-5-T datasheet, A1366LKTTG-5-T pinout, A1366LKTTG-5-T application, or A1366LKTTG-5-T equivalent, this page provides verified technical context, validated pin functions, real-world automotive use cases, and two confirmed alternative parts with documented functional differences and selection guidance.

Technical Context

This IC integrates a BiCMOS interface with a proprietary chopper-stabilized Hall element, dynamic offset cancellation, and digital-domain segmented linear interpolation temperature compensation stored in on-chip EEPROM. Its analog signal path preserves full 120 kHz bandwidth while achieving <±1% typical total accuracy over temperature.

It features ratiometric output scaling, built-in broken-ground-wire detection (VBRK(HIGH)/VBRK(LOW)), undervoltage lockout (VUVLOH = 4 V), and power-on reset (VPORH = 2.6 V). All functions operate across –40°C to 150°C and meet AEC-Q100 Grade 0 requirements.

Key Specifications

Pinout & Package

The A1366LKTTG-5-T is housed in a 4-pin single in-line package (SIP, suffix KT), 1 mm thick, Pb-free with 100% matte tin leadframe plating. It uses TN (straight) leadform and is optimized for through-hole mounting with minimal PCB footprint.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar linear Hall-effect current sensing applications.

Compared with ACS724LLCTR-5AB-T and TLE4971-5U, the A1366LKTTG-5-T uniquely combines factory-programmed 5 mV/G analog output, 120 kHz bandwidth, and <±1% total accuracy - making it optimal for analog-coupled, thermally demanding automotive current loops where calibration flexibility and analog simplicity are critical.

Availability

A1366LKTTG-5-T is available at Aetrix Electronics and suitable for hybrid electric vehicle inverter design, electric power steering (EPS) module production, and automotive DC/DC converter development requiring stable component supply amid obsolescence transitions.

Supply support for A1366LKTTG-5-T 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

Allegro MicroSystems is a U.S.-based designer and manufacturer of high-performance magnetic sensing and power ICs, headquartered in Manchester, NH.

The A1366 product line was developed specifically for high-accuracy, high-bandwidth current sensing in automotive traction and auxiliary power systems - emphasizing AEC-Q100 reliability, temperature-flat performance, and analog interface simplicity.

FAQ

What is the factory-programmed sensitivity of the A1366LKTTG-5-T?

The A1366LKTTG-5-T is factory-programmed to deliver 5 mV/G sensitivity, measured at 200 G and 25°C. This value is trimmed and stored in on-chip EEPROM, ensuring stable performance with <±2.5% drift over –40°C to 150°C and <±1.25% hysteresis after thermal cycling. The A1366LKTTG-5-T maintains this calibrated sensitivity without external adjustment.

Does the A1366LKTTG-5-T support ratiometric operation?

Yes, the A1366LKTTG-5-T provides fully ratiometric output: both its quiescent output voltage (VOUT(Q)) and sensitivity scale linearly with VCC. At VCC = 5 V, VOUT(Q) = 2.500 V ±10 mV; at VCC = 4.5 V, it scales to ~2.25 V. This eliminates need for independent voltage references and simplifies ADC interfacing in systems sharing the same 5 V rail. The A1366LKTTG-5-T achieves ±1% ratiometry error for sensitivity and 0% for VOUT(Q) across supply variation.

What fault-detection features does the A1366LKTTG-5-T include?

The A1366LKTTG-5-T integrates three hardware fault-detection mechanisms: (1) broken ground wire detection (outputs VCC or ~100 mV on VOUT when GND opens), (2) undervoltage lockout (UVLO triggers below 3.5 V and releases above 4 V), and (3) power-on reset (POR holds output high-impedance until VCC exceeds 2.6 V and stabilizes for 64 µs). These features are active across –40°C to 150°C and require no firmware intervention. The A1366LKTTG-5-T implements them via dedicated analog comparators and state machines.

Is the A1366LKTTG-5-T pin-compatible with other A1366 variants?

Yes, all A1366 variants - including A1366LKTTN-1-T, A1366LKTTN-2-T, A1366LKTTN-5-T, and A1366LKTTN-10-T - share identical 4-pin SIP (KT) packaging, pinout, and electrical interface. The only difference is factory-programmed sensitivity (1, 2.5, 5, or 10 mV/G). The A1366LKTTG-5-T can be substituted for other A1366 variants without PCB changes, provided system gain and full-scale range are revalidated.

What is the maximum operating temperature and qualification status of the A1366LKTTG-5-T?

The A1366LKTTG-5-T is rated for continuous operation from –40°C to 150°C ambient and is fully AEC-Q100 Grade 0 qualified. It has passed stress testing including HTOL, TC, UHAST, and ESD per AEC standards. Junction temperature is limited to 165°C, and thermal resistance (RθJA) is 174°C/W on a 1-layer PCB. The A1366LKTTG-5-T's thin 1 mm package and internal temperature compensation ensure stable performance in under-hood automotive locations.