Texas Instruments LM3S618-EQN50-C2

Overview

LM3S618-EQN50-C2 from Texas Instruments is a 32-bit ARM Cortex-M3 microcontroller with 256 KB flash, 64 KB SRAM, integrated ADC (12-bit, 1 MSPS), dual UARTs, SSI, PWM, QEI, and analog comparator - designed for real-time motor control and industrial I/O systems operating at up to 50 MHz.

For engineers reviewing the LM3S618-EQN50-C2 datasheet, LM3S618-EQN50-C2 pinout, LM3S618-EQN50-C2 application, or LM3S618-EQN50-C2 equivalent, key selection criteria include its 50 MHz operation, QEI support for position sensing, hardware PWM with dead-band generation, and 48-pin LQFP package with GPIO remapping capability.

Technical Context

The LM3S618-EQN50-C2 implements the ARM Cortex-M3 core with NVIC, SysTick, and MPU, enabling deterministic interrupt response and memory protection in embedded control loops. It integrates dedicated peripherals including a quadrature encoder interface (QEI) for rotary position decoding and a pulse-width modulator (PWM) with synchronized outputs and fault protection.

Its analog subsystem includes a 12-bit, 1-MSPS ADC with four sample sequencers and internal temperature sensor, plus two independent analog comparators with programmable reference. Clock management supports multiple PLL configurations, with system clock derived from internal precision oscillator or external crystal up to 8 MHz.

Key Specifications

Pinout & Package

LM3S618-EQN50-C2 is housed in a 48-pin LQFP (Leadless Quad Flat Package) with exposed thermal pad, rated for industrial temperature range (–40°C to +85°C) and RoHS-compliant finish.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LM3S618-EQN50-C2, LM3S6965-EQC50-A2 adds Ethernet but increases size and cost, while TM4C123GH6PM offers modern features and longevity at the expense of full hardware compatibility - making LM3S618-EQN50-C2 optimal for cost-sensitive, space-constrained motor control where legacy code stability is critical.

Availability

LM3S618-EQN50-C2 is available at Aetrix Electronics and suitable for industrial motor control, smart sensor nodes, PLC I/O modules, and embedded HMI applications requiring stable component supply and long-lifecycle support.

Supply support for LM3S618-EQN50-C2 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 connectivity technologies for industrial, automotive, and consumer markets.

The Stellaris LM3S series was TI's first ARM Cortex-M3-based microcontroller line, engineered specifically for deterministic real-time control in resource-constrained industrial and motor applications - emphasizing low-latency peripherals and integrated analog functionality.

FAQ

What is the maximum operating frequency of the LM3S618-EQN50-C2?

The LM3S618-EQN50-C2 operates at a maximum system clock frequency of 50 MHz, achieved using its internal PLL with an external crystal (up to 8 MHz) or internal precision oscillator. This frequency is specified across the full industrial temperature range (–40°C to +85°C) and supports real-time execution of motor control algorithms with sub-microsecond interrupt latency. The LM3S618-EQN50-C2 maintains timing compliance under all validated voltage and thermal conditions per TI's Production Data specification DS-LM3S618-15852.2743.

Does the LM3S618-EQN50-C2 support hardware quadrature encoding?

Yes, the LM3S618-EQN50-C2 includes a dedicated Quadrature Encoder Interface (QEI) peripheral with 32-bit position counter, velocity capture, and index pulse detection. It accepts standard A/B/Z encoder signals directly on QEP0–QEP2 pins and performs edge counting, direction detection, and automatic reset on index without CPU intervention. This hardware QEI is documented in Section 15 of the LM3S618 datasheet and is fully functional in the LM3S618-EQN50-C2 variant.

What are the ADC capabilities of the LM3S618-EQN50-C2?

The LM3S618-EQN50-C2 integrates a 12-bit, 1-MSPS successive approximation ADC with eight input channels, four independent sample sequencers, and hardware averaging (up to 64 samples). It supports differential sampling, internal temperature sensor readout, and programmable trigger sources (timer, processor, or external). These ADC features are confirmed in Sections 10.3 and 18 of the official datasheet and apply specifically to the LM3S618-EQN50-C2 configuration.

Is the LM3S618-EQN50-C2 pin-compatible with other LM3S devices?

No, the LM3S618-EQN50-C2 is not universally pin-compatible with other LM3S parts. Its 48-pin LQFP (EQN) package matches only the LM3S608, LM3S610, and LM3S611 in pin count and basic signal mapping, but peripheral assignments (e.g., UART, SSI, PWM) differ significantly across variants. Pin compatibility must be verified per specific function using Table 17.1 (Signals by Pin Number) in the LM3S618 datasheet - the LM3S618-EQN50-C2 has unique GPIO alternate function allocations.

What debug interface does the LM3S618-EQN50-C2 support?

The LM3S618-EQN50-C2 supports JTAG debugging via dedicated TCK, TMS, TDI, TDO, and TRST pins (pins 1, 2, 3, 4, and 5 of the 48-pin LQFP package), compliant with IEEE 1149.1. It also supports SWD (Serial Wire Debug) through shared GPIO pins when configured, enabling use with TI's ICDI-based debuggers like the Stellaris LaunchPad. Debug capabilities are detailed in Section 4 (JTAG Interface) and Section 2.2 of the LM3S618 datasheet, and apply to the LM3S618-EQN50-C2 without modification.