Texas Instruments LM3S1751-IBZ50-A2

Overview

LM3S1751-IBZ50-A2 from Texas Instruments is a 32-bit ARM Cortex-M3 microcontroller with 256 KB flash, 64 KB SRAM, integrated hibernation module, 12-bit ADC (up to 1 MSPS), and dual UARTs. It operates at 50 MHz, supports 3.3 V supply, and targets low-power industrial control systems requiring real-time responsiveness and battery-backed operation.

For engineers reviewing the LM3S1751-IBZ50-A2 datasheet, LM3S1751-IBZ50-A2 pinout, LM3S1751-IBZ50-A2 application, or LM3S1751-IBZ50-A2 equivalent, key selection criteria include hibernation current (≤2 µA), RTC accuracy with external crystal, GPIO interrupt latency (<12 cycles), and UART FIFO depth (16-byte per channel).

Technical Context

The LM3S1751-IBZ50-A2 implements the ARMv7-M architecture with NVIC supporting up to 48 configurable interrupts and 8 priority levels. Its hibernation module integrates a 32.768 kHz RTC, battery-backed RAM (2 KB), and wake-up sources including GPIO, RTC match, and external signal.

Analog subsystem includes one 12-bit ADC with four sample sequencers, hardware averaging (up to 64 samples), and internal temperature sensor. Serial interfaces comprise two UARTs (with IrDA/SIR support), one SSI, and one I²C master/slave controller - all clocked from a programmable PLL-based system clock.

Key Specifications

Pinout & Package

LM3S1751-IBZ50-A2 is housed in a 100-pin LQFP (14 mm × 14 mm, 0.5 mm pitch) package with exposed thermal pad. Pin functions are defined across eight GPIO ports (Port A–H), each supporting multiple peripheral alternate functions and individual digital enable control.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LM3S1968-IBZ50-A2, LM3S1751-IBZ50-A2 removes USB hardware to reduce die size and cost while retaining identical hibernation, CAN, and analog capabilities. Against TM4C123GH6PM, it lacks FPU and has higher hibernate current but maintains full register compatibility for legacy code migration where USB and extreme low-power are not required.

Availability

LM3S1751-IBZ50-A2 is available at Aetrix Electronics and suitable for industrial sensor nodes, smart energy meters, motor control interfaces, and building automation controllers requiring stable component supply and long-lifecycle support.

Supply support for LM3S1751-IBZ50-A2 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 wireless technologies with over 90 years of innovation in industrial, automotive, and consumer electronics.

The Stellaris LM3S series was designed as TI's first ARM Cortex-M3-based microcontroller family targeting cost-sensitive, real-time industrial control applications with integrated analog, communication, and ultra-low-power hibernation features.

FAQ

What is the maximum operating frequency of the LM3S1751-IBZ50-A2?

The LM3S1751-IBZ50-A2 operates at a maximum system clock frequency of 50 MHz, derived from an internal PLL that accepts input from either the main oscillator (4–25 MHz) or precision internal oscillator (precision trimmed to ±1.5%). This frequency is specified under industrial temperature range (-40°C to +85°C) and 3.3 V supply conditions. The LM3S1751-IBZ50-A2 delivers consistent 50 MHz performance without requiring external clock conditioning circuitry.

Does the LM3S1751-IBZ50-A2 support CAN bus communication?

Yes, the LM3S1751-IBZ50-A2 integrates a full CAN 2.0B-compliant controller with 32 message objects, programmable bit timing, and automatic retransmission. Pins PF0 and PF3 are dedicated to CAN0RX and CAN0TX functions in the 100-pin LQFP package. The LM3S1751-IBZ50-A2 requires only an external CAN transceiver (e.g., SN65HVD230) to complete the physical layer - no additional protocol firmware is needed.

What is the hibernation current specification for the LM3S1751-IBZ50-A2?

The LM3S1751-IBZ50-A2 achieves ≤2 µA hibernation current when the hibernation module is active, RTC is running from a 32.768 kHz crystal, and 2 KB of battery-backed RAM is retained. This value is measured at 3.3 V and 25°C with all other peripherals disabled. The LM3S1751-IBZ50-A2 maintains this ultra-low current while supporting wake-up via GPIO, RTC alarm, or external signal - enabling multi-year operation on primary batteries.

How many UART interfaces does the LM3S1751-IBZ50-A2 provide?

The LM3S1751-IBZ50-A2 provides two independent UART modules (UART0 and UART1), each with 16-byte transmit and receive FIFOs, programmable baud-rate generation, and support for IrDA and SIR protocols. UART0 is mapped to PA0/PA1, and UART1 to PD0/PD1 in the default configuration. The LM3S1751-IBZ50-A2 supports simultaneous full-duplex operation on both channels with DMA-triggered transfers to minimize CPU load.

Is the LM3S1751-IBZ50-A2 pin-compatible with other Stellaris LM3S devices?

The LM3S1751-IBZ50-A2 uses a 100-pin LQFP package with a specific pinout defined in the SPMS029I datasheet. While several LM3S devices share the same 100-pin footprint (e.g., LM3S1968-IBZ50-A2), pin functions differ across variants - particularly for USB, Ethernet, and additional PWM channels. The LM3S1751-IBZ50-A2 is not pin-compatible with those parts due to differing peripheral mappings and missing USB signals; PCB layout must be verified against its exact pin assignment table.