Texas Instruments RM42L432PZT

Overview

RM42L432PZT from Texas Instruments is a safety-certified 32-bit ARM Cortex-R4 microcontroller for functional safety applications, featuring dual lockstep CPUs, 384KB flash with ECC, 32KB RAM with ECC, 100-MHz operation, and integrated DCAN, N2HET, and MibADC peripherals - deployed in industrial PLCs and medical infusion pumps.

For engineers reviewing the RM42L432PZT datasheet, RM42L432PZT pinout, RM42L432PZT application, or RM42L432PZT equivalent, this page delivers verified technical context, validated pin functions, safety-critical feature mapping, and real-world use-case alignment for IEC 61508 SIL-3 and ISO 26262 ASIL-D system design.

Technical Context

The RM42L432PZT implements a dual-CPU lockstep architecture with built-in self-test (BIST), ECC on flash and SRAM, parity protection on peripheral memories (N2HET, MibADC, VIM), and an Error Signaling Module (ESM) that asserts nERROR on fault detection. Its FMPLL generates internal clocks up to 100 MHz with slip detection, while the Global Clock Module (GCM) routes five clock sources across domains.

Peripheral integration includes two DCAN controllers (DCAN1 with 32 mailboxes, DCAN2 with 16 mailboxes), a 19-pin N2HET coprocessor with HTU DMA support and MPU, a 12-bit 16-channel MibADC with 64-word parity-protected buffer, and eQEP for motor position feedback - all accessible via 45 GPIO pins, 8 of which are interrupt-capable.

Key Specifications

Pinout & Package

RM42L432PZT is housed in a 100-pin LQFP (PZ) package with 0.5-mm pitch, thermal pad exposed on underside, and RoHS-compliant green finish. Pin functions support multiplexing across safety-critical peripherals including DCAN, N2HET, MibADC, SPI, LIN, and GPIO.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar safety microcontroller applications.

Compared with RM42L432PZT, RM44L920PZ offers greater compute headroom and memory for advanced control algorithms, while RM41L232PZ reduces bill-of-materials cost at the expense of CAN redundancy and eQEP - making RM42L432PZT the optimal balance for mid-tier industrial safety systems requiring dual CAN, N2HET, and eQEP in a 100-pin footprint.

Availability

RM42L432PZT is available at Aetrix Electronics and suitable for industrial safety PLCs, medical infusion pumps, wind turbine pitch control, and robotic surgery actuators requiring stable component supply and long-term lifecycle assurance.

Supply support for RM42L432PZT 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, delivering analog and embedded processing solutions for industrial, automotive, and communications markets.

The RM42L432PZT belongs to TI's Hercules™ ARM-based safety microcontroller family, designed specifically for IEC 61508 SIL-3 and ISO 26262 ASIL-D applications requiring hardware-based fault detection and recovery.

FAQ

What safety certifications does the RM42L432PZT support?

The RM42L432PZT is architected to support IEC 61508 SIL-3 and ISO 26262 ASIL-D compliance through integrated features including dual lockstep CPUs, memory ECC, peripheral parity, BIST, ESM with nERROR, and clock/voltage monitoring. TI provides safety manuals, FMEDA reports, and diagnostic software libraries to accelerate certification - but final system-level validation remains the responsibility of the end equipment manufacturer. RM42L432PZT itself is not pre-certified; it enables certified system design.

Does the RM42L432PZT include hardware support for CAN FD?

No, the RM42L432PZT supports only Classical CAN (CAN 2.0A/B) up to 1 Mbps via its two DCAN modules. It does not implement CAN FD protocol features such as flexible data-rate, extended data length, or CRC enhancements. For CAN FD capability, TI recommends the RM57L843 or later Hercules TMS570LS series devices. RM42L432PZT remains fully compatible with legacy CAN networks used in industrial safety and medical systems.

How many N2HET pins are available on the RM42L432PZT in the 100-pin PZ package?

The RM42L432PZT provides 19 dedicated N2HET I/O pins in the 100-pin PZ package: N2HET[0], [2], [4], [6], [8], [10], [12], [14], [16], [18], [19], [20], [22], [24], [26], [28], [29], [30], and [31]. These are confirmed in Table 4-1 of the SPNS180B datasheet and physically mapped to pins 100, 22, 25, 26, 74, 83, 89, 90, 97, 98, 27, 11, 64, 39, 58, 18, 68, 12, and 93 respectively.

What is the role of the nERROR pin on the RM42L432PZT?

The nERROR pin (Pin 82) is an active-low, open-drain output driven by the Error Signaling Module (ESM) to indicate detected faults including CPU mismatch, memory ECC errors, clock failure, or voltage monitor violation. It requires an external pullup resistor and can be monitored by external safety logic or watchdog circuits. The RM42L432PZT asserts nERROR synchronously with fault detection - enabling immediate system-level response without software intervention.

Can the RM42L432PZT operate with a 3.3-V I/O supply while using 1.2-V core voltage?

Yes, the RM42L432PZT is designed for split-rail operation: nominal VCC = 1.2 V ±0.06 V for the core/CPU domain, and nominal VCCIO = 3.3 V ±0.3 V for I/O, ADC, and peripheral interfaces. This allows direct interfacing with 3.3-V sensors, transceivers, and logic without level shifters. The device specifies separate power sequencing requirements - VCCIO must be stable before VCC, and both must meet recommended operating conditions per Section 5.4 of the datasheet.