NXP Semiconductors KMA321/AZ

Overview

KMA321/A from NXP Semiconductors is a single-channel magnetoresistive (MR) programmable angle sensor IC integrating MR bridges and mixed-signal circuitry in one SIL4 package. It delivers ratiometric analog voltage or SENT-compliant digital output (SAE J2716), supports multipoint calibration (17-point or 7-point), operates up to 180 °C, and features fail-safe NVM with lock-bit protection - used in automotive throttle and steering position sensing where PCB-less integration and ASIL-C compliance are required.

For engineers reviewing the KMA321/A datasheet, KMA321/A pinout, KMA321/A application, or KMA321/A equivalent, this page provides verified technical context on its CORDIC-based angular calculation, SENT protocol variants (A.1/H.1, A.3/H.4, H.3), clamping behavior, power-loss detection, and OEM register programming via one-wire interface - all critical for functional safety validation and ECU interface design.

Technical Context

The KMA321/A converts orthogonal MR bridge signals into digital angle data using a hardware CORDIC algorithm, followed by configurable DAC (for analog output) or SENT frame generation (for digital output). Its signal chain includes integrated SD-ADC, temperature sensor, auxiliary ADC for magnetic field conversion check, and digital filtering with averaging.

Configuration is performed via one-wire interface (OWI) on pin OUT/DATA, accessing user-programmable NVM registers including SYS_SETTING (bit 12 selects analog/digital mode), SENT_SETTING1 (CRC type), SENT_SETTING2 (voltage/temperature thresholds), and eight 12-bit OEM ID registers. Power-loss detection pulls OUT/DATA to remaining rail if VDD or GND fails.

Key Specifications

Pinout & Package

Package: SIL4 (SOT1188-3), plastic single in-line package optimized for PCB-less mounting with integrated EMC filters.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar magnetic angle sensing applications.

Compared with AMS AS5055A and Infineon TLE5012B, the KMA321/A uniquely combines SENT protocol flexibility (A.1/H.1, A.3/H.4, H.3), ASIL-C SEooC certification, 180 °C operation, and dedicated OEM register space - making it optimal for automotive applications requiring embedded diagnostics, thermal resilience, and ECU-level interoperability without added interface complexity.

Availability

KMA321/A is available at Aetrix Electronics and suitable for automotive throttle position sensing, steering angle sensing, brake pedal position sensing, and transmission gear selector sensing requiring stable component supply across extended temperature ranges and functional safety compliance.

Supply support for KMA321/A 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

NXP Semiconductors is a global semiconductor company headquartered in Eindhoven, Netherlands, specializing in secure connectivity solutions for automotive, industrial, and IoT markets.

The KMA321/A belongs to NXP's high-reliability magnetic sensor product line, designed specifically for automotive functional safety applications demanding ASIL-C compliance, extreme temperature operation, and robust EMC performance in PCB-less installations.

FAQ

What output interfaces does the KMA321/A support?

The KMA321/A supports two mutually exclusive output modes selectable via SYS_SETTING register bit 12: ratiometric analog voltage (0–100% VDD) or SENT digital output compliant with SAE J2716 revisions FEB2008, JAN2010, and APR2016. The SENT mode supports protocol formats A.1/H.1 (dual slope), A.3/H.4 (single secure), and H.3 (high-speed 12-bit), all transmitted on the same OUT/DATA pin. This dual-mode capability allows reuse of the KMA321/A across analog and digital ECU platforms without hardware redesign.

How is the KMA321/A calibrated and programmed?

The KMA321/A is factory-calibrated and pre-programmed for immediate use, but supports field reconfiguration via its one-wire interface (OWI) on pin OUT/DATA. Users can adjust zero angle, angular range, clamping voltages, and SENT parameters (e.g., CRC type, clock tick duration) by writing to NVM registers. Eight 12-bit OEM registers store customer-specific identifiers. A lock bit permanently protects NVM contents after final programming - ensuring calibration integrity in production environments.

Does the KMA321/A meet automotive safety standards?

Yes, the KMA321/A is AEC-Q100 Rev-H qualified and ISO 26262 ASIL-C capable as a safety element out of context (SEooC). It implements 12 independent ASIL safety mechanisms including CORDIC range check, SD-ADC range check, BIST encoding check, and magnetic field conversion verification. Diagnostic coverage is enhanced by SENT STATUS nibble bits (diagnostic/pre-warning), CRC+EDC on DATA nibbles, and power-loss detection - all documented in the KMA321/A safety manual.

What is the operating temperature range of the KMA321/A?

The KMA321/A operates from −40 °C to +180 °C, validated per AEC-Q100 stress test conditions. This extended range enables deployment in high-temperature under-hood locations such as engine control modules, transmission control units, and electric power steering (EPS) motor housings. The integrated temperature sensor and auxiliary ADC provide on-chip thermal monitoring for system-level derating decisions.

Can the KMA321/A operate without external components?

Yes, the KMA321/A is designed for PCB-less operation with integrated filters, regulators (analog clean, analog switching, digital), and capacitors. It requires only VDD, GND, and a magnet - no external resistors, capacitors, or voltage references. This reduces system BOM cost and improves EMC robustness. The module's SIL4 package and internal power-loss detection further simplify mechanical integration in space-constrained automotive actuators.