Texas Instruments LM3S808-EQN50-C2

Overview

LM3S808-EQN50-C2 from Texas Instruments is a 32-bit ARM Cortex-M3 microcontroller with 64 KB flash, 24 KB SRAM, integrated ADC (10-bit, 8-channel), dual UARTs, I²C, SSI, and PWM-capable timers. It operates at up to 50 MHz and supports industrial motor control and sensor interface applications.

For engineers reviewing the LM3S808-EQN50-C2 datasheet, LM3S808-EQN50-C2 pinout, LM3S808-EQN50-C2 application, or LM3S808-EQN50-C2 equivalent, key selection criteria include its 50 MHz CPU clock, QFP-100 package, integrated analog peripherals, and support for real-time deterministic execution in embedded control systems.

Technical Context

The LM3S808-EQN50-C2 implements the ARM Cortex-M3 core with NVIC, SysTick, and MPU-enabling low-latency interrupt handling and memory protection. Its system-level design includes on-chip LDO regulation, configurable clock tree (PLL + internal oscillator), and power management supporting Sleep/Deep-Sleep modes.

Peripherals are memory-mapped and register-accessible via APB bus: dual UARTs with FIFOs, I²C master/slave, SSI with frame formatting, 8-channel 10-bit ADC with sequencer and temperature sensor, and four 16/32-bit GPTMs with PWM and RTC capability.

Key Specifications

Pinout & Package

LM3S808-EQN50-C2 is housed in a 100-pin Low-Profile Quad Flat Package (LQFP), 14 mm × 14 mm, 0.5 mm pitch, with exposed thermal pad. Pinout supports full GPIO multiplexing, dedicated JTAG debug, and independent analog/digital power domains.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LM3S808-EQN50-C2, LM3S811-EQN50-C2 offers more flash but removes thermal sensing, while TM4C123GH6PM delivers significantly higher compute throughput and peripheral richness at the cost of increased BOM complexity and power consumption.

Availability

LM3S808-EQN50-C2 is available at Aetrix Electronics and suitable for industrial motor control, smart sensor nodes, PLC I/O modules, and HMI controllers requiring stable component supply and long-term obsolescence management.

Supply support for LM3S808-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, delivering analog, embedded processing, and connectivity solutions across industrial, automotive, and consumer markets.

The Stellaris LM3S series was designed as TI's first ARM-based microcontroller line targeting cost-sensitive, real-time embedded control applications with integrated analog and communication peripherals - bridging the gap between legacy 8/16-bit MCUs and high-end application processors.

FAQ

What is the maximum operating frequency of the LM3S808-EQN50-C2?

The LM3S808-EQN50-C2 operates at a maximum CPU clock frequency of 50 MHz, achieved via its internal PLL driven by either the 6 MHz precision RC oscillator or an external crystal. This speed enables deterministic execution of motor control algorithms and real-time communication stacks without external acceleration. The LM3S808-EQN50-C2 maintains full peripheral functionality-including ADC sampling, UART transmission, and PWM output-at this rated frequency under specified voltage and temperature conditions.

Does the LM3S808-EQN50-C2 include an internal temperature sensor?

Yes, the LM3S808-EQN50-C2 integrates a factory-calibrated on-die temperature sensor accessible through ADC channel 6 (AIN6). It provides ±3°C accuracy across the industrial temperature range (–40°C to +85°C) and requires no external components. This sensor is directly supported in StellarisWare driver libraries, and the LM3S808-EQN50-C2 firmware can read it using standard ADC sequence configuration without additional hardware.

What debug interfaces does the LM3S808-EQN50-C2 support?

The LM3S808-EQN50-C2 supports IEEE 1149.1 JTAG and Serial Wire Debug (SWD) via its five-pin debug header (TCK, TMS, TDI, TDO, nTRST). Both interfaces provide full boundary-scan visibility, flash programming, and real-time breakpoint debugging. The LM3S808-EQN50-C2 is compatible with TI's ICDI-based debug tools, Keil ULINK, and Segger J-Link, enabling seamless integration into established embedded development workflows.

Is the LM3S808-EQN50-C2 pin-compatible with other LM3S devices?

No, the LM3S808-EQN50-C2 is not pin-compatible with other LM3S variants such as LM3S811 or LM3S3748, despite sharing the same 100-pin LQFP package. Pin assignments for peripherals-including UART, I²C, SSI, and ADC-differ across the LM3S family due to varying peripheral counts and routing constraints. Migration requires PCB layout revision and firmware adaptation, even when retaining the same package footprint.

What power supply requirements does the LM3S808-EQN50-C2 have?

The LM3S808-EQN50-C2 requires three separate supply connections: VDDC (1.8–2.5 V for core logic), VDDA (2.7–3.6 V for analog circuits), and VDD (2.7–3.6 V for I/O). These rails must be decoupled per TI's layout guidelines, with dedicated GNDC/GNDA/GND planes. The LM3S808-EQN50-C2 includes an internal LDO regulator that derives VDDC from VDD, simplifying power design but requiring careful sequencing during startup to meet reset timing specifications.