Texas Instruments TMS37145TEAIE

Overview

TMS37145TEAIE from Texas Instruments is a batteryless LF RFID transponder IC for automotive immobilizer systems, integrating DST80 authentication logic, 75-byte EEPROM (48 bytes user-accessible), 32-bit unique serial number, and PWM communication format in a 12 mm × 6 mm wedge package. It operates at 134.2 kHz, supports HDX half-duplex protocol, achieves 42 ms fast authentication, and meets IP68 environmental rating.

For engineers reviewing the TMS37145TEAIE datasheet, TMS37145TEAIE pinout, TMS37145TEAIE application, or TMS37145TEAIE equivalent, key selection criteria include LF resonant frequency alignment, DST80 mutual authentication timing (65 ms), EEPROM page-lock security model, HF/LF coexistence immunity, and wedge-form factor integration into key fob housings.

Technical Context

The TMS37145TEAIE implements a dedicated DST80 cryptographic coprocessor with fixed 80-bit key length and supports both 5-byte challenge/3-byte response and legacy 4-byte challenge modes. Its HDX (half-duplex) communication uses FSK uplink (7.9 kbit/s typ) and PPM downlink (2 kbit/s typ), with integrated resonant frequency trimming via LF field or test interface.

Authentication execution occurs entirely on-chip without external microcontroller involvement: fast authentication completes in ≤42 ms; mutual authentication in ≤65 ms. EEPROM pages are individually lockable, write-only keys are irreversibly programmable, and protected pages require mutual authentication for reprogramming - enforcing hardware-enforced security boundaries.

Key Specifications

Pinout & Package

Wedge package (RFIDP-TEA), dimensions 12.0 mm × 6.0 mm × 3.0 mm, plastic body, no external pins - device functions as a monolithic RF-coupled transponder with internal coil interface and no user-accessible terminals.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar digital signature transponder applications.

Compared with TMS37145TEAIEG and third-party DST80 variants, the TMS37145TEAIE delivers superior field reliability through TI's proprietary selective addressing and on-chip resonant trimming - critical for first-time learn-in success and long-term read-range stability in production key fobs.

Availability

TMS37145TEAIE is available at Aetrix Electronics and suitable for automotive key fob immobilizers, heavy equipment access tokens, and industrial machinery authorization modules requiring stable component supply, long-lifecycle support, and qualified production-grade RF performance.

Supply support for TMS37145TEAIE 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 headquartered in Dallas, Texas, specializing in analog, embedded processing, and wireless connectivity solutions for automotive, industrial, and consumer markets.

The TMS37145 product line delivers batteryless LF RFID transponders optimized for automotive immobilizer and secure access applications, with hardware-enforced cryptographic authentication and environmental resilience built into the silicon.

FAQ

What communication format does the TMS37145TEAIE use?

The TMS37145TEAIE uses PWM (pulse-width modulation) for its downlink communication. This format is fixed per the part number suffix "TEAIE" and cannot be reconfigured in-system. It is electrically and protocol-compatible with ISO 11784/11785 readers supporting PWM modulation at 134.2 kHz, distinguishing it from the PPM variant TMS37145TEAIEG.

Does the TMS37145TEAIE require an external power source or battery?

No, the TMS37145TEAIE is fully batteryless and derives operating power and clock signal directly from the reader's 134.2 kHz electromagnetic field. Its integrated power management circuitry harvests energy during the downlink phase to sustain authentication computation and EEPROM access - a core design requirement for key fob longevity and maintenance-free operation.

How many times can the EEPROM in the TMS37145TEAIE be rewritten?

The EEPROM in the TMS37145TEAIE is rated for a minimum of 200,000 write-erase cycles at 25°C ambient temperature. Each of the nine user pages can be independently programmed and locked, and once locked, pages are irreversibly protected against further writes - ensuring long-term integrity of stored keys and configuration data over the device's operational lifetime.

What is the purpose of the selective addressing mode in the TMS37145TEAIE?

The selective addressing mode in the TMS37145TEAIE enables secure, collision-free learn-in sequences during key programming by allowing the reader to target a specific transponder among multiple nearby units. This prevents eavesdropping or misprogramming in multi-key environments and is essential for reliable dealer-level immobilizer enrollment - a feature not present in basic DST80 implementations.

Is the TMS37145TEAIE compliant with international automotive standards?

Yes, the TMS37145TEAIE meets ISO 11784/11785 for LF RFID air interface protocols and is qualified for automotive use with -40°C to +85°C operating temperature, IP68 ingress protection, and IEC 68-2-27/6 shock/vibration ratings. Its 134.2 kHz resonance, 80-bit DST80 authentication, and 42 ms fast authentication align with OEM immobilizer system requirements globally.