Texas Instruments LM3S801-EQN50-C2T

Overview

LM3S801-EQN50-C2T from Texas Instruments is a 32-bit ARM Cortex-M3 microcontroller with 64 KB flash, 8 KB SRAM, and integrated analog comparators, UART, I²C, SSI, PWM, QEI, and watchdog timer - designed for low-cost industrial control and sensor interface applications operating at up to 50 MHz.

For engineers reviewing the LM3S801-EQN50-C2T datasheet, LM3S801-EQN50-C2T pinout, LM3S801-EQN50-C2T application, or LM3S801-EQN50-C2T equivalent, key selection criteria include its 48-pin QFP package, 50 MHz maximum CPU frequency, 2.25–3.6 V supply range, single analog comparator with internal reference, and lack of ADC or DAC peripherals.

Technical Context

The LM3S801-EQN50-C2T implements the ARM Cortex-M3 processor core with Thumb-2 instruction set, NVIC-based interrupt handling, and SysTick timer. It integrates a system control block with clock gating, reset management, and power control logic supporting sleep modes (sleep/deep-sleep) with wake-up via GPIO or peripheral interrupts.

Peripherals include one UART, one I²C master/slave, one SSI (SPI-compatible), two 16-bit general-purpose timers (GPTM), one watchdog timer, one quadrature encoder interface (QEI), and one analog comparator - all mapped to dedicated pins in the 48-pin LQFP package without on-chip ADC, DAC, or USB.

Key Specifications

Pinout & Package

The LM3S801-EQN50-C2T is housed in a 48-pin LQFP (Low-profile Quad Flat Package) with 0.5 mm lead pitch, thermal pad exposed on underside, and JEDEC MS-026 compliant dimensions (7 mm × 7 mm).

Key Features

Applications

Equivalent & Alternatives

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

Compared with LM3S101-IQN50-C2 and TM4C123GH6PM, the LM3S801-EQN50-C2T uniquely balances minimal BOM cost with QEI and comparator integration - making it optimal for cost-constrained motion sensing where ADC is unnecessary and legacy Stellaris toolchain support is required.

Availability

LM3S801-EQN50-C2T is available at Aetrix Electronics and suitable for industrial motor control, sensor interface, serial gateway, and embedded appliance applications requiring stable component supply and long-term availability assurance.

Supply support for LM3S801-EQN50-C2T 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 since 1930.

The Stellaris LM3S series was TI's first ARM Cortex-M3-based microcontroller line, targeting cost-sensitive industrial and consumer embedded systems requiring real-time performance without complex peripherals like USB or Ethernet.

FAQ

What is the maximum operating frequency of the LM3S801-EQN50-C2T?

The LM3S801-EQN50-C2T operates at a maximum CPU clock frequency of 50 MHz. This rating is guaranteed across the full industrial temperature range (–40°C to +85°C) and specified supply voltage range (2.25 V to 3.6 V). The device achieves this speed using an on-chip PLL that multiplies the crystal or external clock input, and all timing parameters in the datasheet - including flash wait states and peripheral setup/hold times - are validated at 50 MHz for the LM3S801-EQN50-C2T.

Does the LM3S801-EQN50-C2T include an analog-to-digital converter (ADC)?

No, the LM3S801-EQN50-C2T does not include an ADC. Its analog capability is limited to a single analog comparator (COMP0) with programmable internal reference voltages (1.25 V or 2.5 V). Unlike higher-tier Stellaris parts such as the LM3S811 or LM3S9B92, the LM3S801-EQN50-C2T omits ADC, DAC, and operational amplifiers - making it suitable for threshold-detection-only applications rather than full analog signal acquisition.

What communication interfaces are supported by the LM3S801-EQN50-C2T?

The LM3S801-EQN50-C2T supports UART, I²C, and SSI (SPI-compatible) interfaces. It includes one UART module with FIFO and modem control signals, one I²C master/slave controller compliant with standard-mode (100 kbps) and fast-mode (400 kbps) specifications, and one SSI module configurable for Motorola, TI, or National Semiconductor SPI protocols. No CAN, USB, or Ethernet interfaces are present on the LM3S801-EQN50-C2T.

Is the LM3S801-EQN50-C2T pin-compatible with other Stellaris LM3S devices?

No, the LM3S801-EQN50-C2T is not pin-compatible with most other LM3S devices. While it shares the same 48-pin LQFP package footprint as the LM3S101 and LM3S300, pin functions differ significantly - especially for peripherals like QEI, comparator inputs, and clock sources. For example, QEI phase A/B signals on the LM3S801-EQN50-C2T map to GPIOB[0]/[1], whereas those pins serve different roles on the LM3S101. Direct replacement requires board-level redesign.

What debug interface does the LM3S801-EQN50-C2T use?

The LM3S801-EQN50-C2T uses a 5-pin JTAG interface (TCK, TMS, TDI, TDO, nTRST) for debugging and programming. It supports boundary-scan testing, real-time debugging via SWD-compatible tools (e.g., TI XDS100v2), and flash programming through the JTAG port. The device does not support SWD-only operation - JTAG is the sole standardized debug interface defined for the LM3S801-EQN50-C2T in the official Texas Instruments production datasheet.