Texas Instruments LM3S8938-EQC50-A2T

Overview

LM3S8938-EQC50-A2T from Texas Instruments is a 32-bit ARM Cortex-M3 microcontroller with 256 KB flash, 64 KB SRAM, integrated CAN 2.0B controller, 12-bit ADC (up to 1 MSPS), and hibernation module supporting RTC and battery-backed memory. It operates at 50 MHz and targets industrial motor control and embedded automation systems requiring deterministic real-time response.

For engineers reviewing the LM3S8938-EQC50-A2T datasheet, LM3S8938-EQC50-A2T pinout, LM3S8938-EQC50-A2T application, or LM3S8938-EQC50-A2T equivalent, key selection criteria include CAN interface support, hibernation power management, analog acquisition performance, and Cortex-M3 interrupt latency in safety-critical control loops.

Technical Context

The LM3S8938-EQC50-A2T implements the ARMv7-M architecture with NVIC supporting up to 64 interrupt lines, 8 priority levels, and tail-chaining for sub-12-cycle interrupt latency. Its system-level peripherals include a hibernation module with dedicated 32.768 kHz crystal oscillator input, battery-backed RAM, and wake-up on RTC match or external GPIO event.

Analog subsystem integrates four independent 12-bit ADC sample sequencers with hardware averaging, differential input capability, and internal temperature sensor. Serial connectivity includes two UARTs (one with IrDA/SIR), two SSI interfaces, one I²C master/slave, and one CAN 2.0B controller compliant with ISO 11898-1.

Key Specifications

Pinout & Package

LM3S8938-EQC50-A2T is housed in a 100-pin LQFP (14 mm × 14 mm, 0.5 mm pitch) package with exposed thermal pad. Pin assignments are defined per TI SPMS174I datasheet revision I.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TM4C123GH6PM and STM32F103VET6, the LM3S8938-EQC50-A2T provides verified hibernation power management and CAN 2.0B compliance in a mature, production-qualified platform-ideal for cost-sensitive industrial designs where extended temperature operation and deterministic interrupt latency are prioritized over raw clock speed.

Availability

LM3S8938-EQC50-A2T is available at Aetrix Electronics and suitable for industrial motor control, building automation nodes, factory floor PLC I/O modules, and energy meter communication gateways requiring stable component supply across long product lifecycles.

Supply support for LM3S8938-EQC50-A2T 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, embedded processing, and wireless technologies for industrial, automotive, and consumer applications.

The Stellaris LM3S series was designed as the first ARM Cortex-M3-based microcontroller family for industrial real-time control, emphasizing deterministic interrupt handling, integrated analog peripherals, and robust power management for harsh environments.

FAQ

What is the maximum operating frequency of the LM3S8938-EQC50-A2T?

The LM3S8938-EQC50-A2T operates at a maximum system clock frequency of 50 MHz, as specified in the TI SPMS174I datasheet. This frequency is achieved using the internal PLL with an external crystal or oscillator input. The Cortex-M3 core executes instructions at this rate, enabling real-time control tasks such as motor commutation and CAN message processing within strict timing windows. The LM3S8938-EQC50-A2T does not support overclocking beyond 50 MHz under standard operating conditions.

Does the LM3S8938-EQC50-A2T support hibernation mode with RTC and battery backup?

Yes, the LM3S8938-EQC50-A2T includes a dedicated hibernation module that supports real-time clock operation, battery-backed RAM (2 KB), and wake-up on RTC match or external GPIO event. When powered from a coin cell or supercapacitor, the device draws less than 1 µA in hibernation mode while maintaining accurate timekeeping and preserving critical state data. This capability is confirmed in Section 6 of the SPMS174I datasheet and is a defining feature of the LM3S8938-EQC50-A2T variant.

How many CAN controllers does the LM3S8938-EQC50-A2T integrate?

The LM3S8938-EQC50-A2T integrates one CAN 2.0B-compliant controller supporting bit rates up to 1 Mbps, 32 message objects, and mask-based filtering. It includes dedicated CAN0RX and CAN0TX pins mapped to GPIO port D, and its register set enables full mailbox configuration, error handling, and status monitoring. This single CAN interface is documented in Section 15 of the SPMS174I datasheet and is functionally identical across all LM3S8938 variants.

What ADC resolution and sampling rate does the LM3S8938-EQC50-A2T provide?

The LM3S8938-EQC50-A2T features a 12-bit successive-approximation ADC with up to 1 MSPS aggregate sampling rate across four sample sequencers. Each sequencer supports hardware averaging of up to 64 samples per conversion, improving effective resolution without CPU overhead. Differential input mode and internal temperature sensor are also supported. These specifications are validated in Section 11 of the SPMS174I datasheet and apply directly to the LM3S8938-EQC50-A2T.

Is the LM3S8938-EQC50-A2T pin-compatible with other LM3S8938 variants?

Yes, the LM3S8938-EQC50-A2T shares the same 100-pin LQFP package and pinout with other LM3S8938 variants including LM3S8938-IQC50-A2T and LM3S8938-ERD50-A2T. Differences between these variants relate only to temperature grade (industrial vs. extended), packaging (LQFP vs. QFN), and screening level-not pin assignment or electrical behavior. This compatibility is confirmed in TI's LM3S8938 ordering information table and allows direct substitution in existing PCB layouts.