Texas Instruments LM3S1637-IBZ50-A2T

Overview

LM3S1637-IBZ50-A2T from Texas Instruments is a 32-bit ARM Cortex-M3 microcontroller with 256 KB flash, 32 KB SRAM, integrated hibernation module, 12-bit ADC (8-channel), dual UARTs, I²C, SSI, PWM, and GPIO-designed for low-power industrial control and motor drive applications.

For engineers reviewing the LM3S1637-IBZ50-A2T datasheet, LM3S1637-IBZ50-A2T pinout, LM3S1637-IBZ50-A2T application, or LM3S1637-IBZ50-A2T equivalent, key selection criteria include hibernation support, 50 MHz CPU clock, integrated RTC, battery-backed memory, and motor control peripherals including PWM and analog comparators.

Technical Context

The LM3S1637-IBZ50-A2T implements the ARM Cortex-M3 core with Thumb-2 instruction set, NVIC with 48 interrupt lines, and SysTick timer. It integrates a dedicated hibernation module supporting RTC, battery-backed RAM, and wake-up from deep-sleep using external pins or RTC match.

Peripherals include two UARTs with IrDA/SIR support, one I²C master/slave interface, one SSI port, eight-channel 12-bit ADC with hardware averaging, two analog comparators, and six PWM generator blocks with fault protection-enabling closed-loop motor control without external timing ICs.

Key Specifications

Pinout & Package

LM3S1637-IBZ50-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 SPMS028I datasheet Rev I, Section 8 (GPIO) and Section 17 (Signal Descriptions).

Key Features

Applications

Equivalent & Alternatives

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

Compared with LM3S1968-IBZ50-A2T and TM4C123GH6PM, the LM3S1637-IBZ50-A2T provides optimal balance of hibernation capability, motor control peripherals, and cost for battery-aware industrial controllers where Ethernet or FPU are unnecessary.

Availability

LM3S1637-IBZ50-A2T is available at Aetrix Electronics and suitable for industrial motor control, smart sensor nodes, PLC I/O modules, and medical infusion pump controllers requiring stable component supply and long-term availability.

Supply support for LM3S1637-IBZ50-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, specializing in analog, embedded processing, and digital signal processing technologies since 1930.

The Stellaris LM3S series was designed specifically for cost-sensitive, low-power industrial and motor control applications-emphasizing integration of hibernation, analog, and timing peripherals into a single ARM-based MCU.

FAQ

What is the maximum operating frequency of the LM3S1637-IBZ50-A2T?

The LM3S1637-IBZ50-A2T operates at a maximum CPU clock frequency of 50 MHz, as specified in the Texas Instruments SPMS028I datasheet. This frequency is achieved using the internal PLL driven by an external crystal (1–25 MHz) or oscillator. The 50 MHz rating applies across the full industrial temperature range (–40°C to +85°C) under specified voltage conditions (VDD = 3.3 V ±10%). The LM3S1637-IBZ50-A2T maintains deterministic interrupt latency and real-time performance at this speed.

Does the LM3S1637-IBZ50-A2T support hibernation mode with battery backup?

Yes, the LM3S1637-IBZ50-A2T includes a dedicated hibernation module that supports battery-backed operation. When powered from a coin-cell or supercapacitor via the VBAT pin, it retains RTC timekeeping, stores up to 2 KB of data in battery-backed RAM, and wakes on RTC match or external pin assertion. Current draw in hibernate mode is less than 2 µA, as measured per TI's characterization in SPMS028I Section 6. The LM3S1637-IBZ50-A2T requires no external components beyond the backup power source to enable this feature.

How many ADC channels does the LM3S1637-IBZ50-A2T have, and what is its resolution?

The LM3S1637-IBZ50-A2T integrates a single 12-bit successive-approximation ADC with eight analog input channels (AIN0–AIN7). It supports programmable sample rates up to 1 MSPS and includes hardware averaging across up to 64 samples to improve effective resolution. The ADC features internal temperature sensing and differential input capability on select channels. All specifications-including INL, DNL, and conversion time-are documented in SPMS028I Section 11. The LM3S1637-IBZ50-A2T ADC is calibrated at factory and requires no user trimming for standard operation.

What communication interfaces are available on the LM3S1637-IBZ50-A2T?

The LM3S1637-IBZ50-A2T provides dual UARTs (one supporting IrDA physical layer), one I²C master/slave interface, and one SSI (SPI-compatible) port. Each interface is independently clocked and mapped to multiple GPIO pins for layout flexibility. UART0 supports full modem control signals; UART1 includes SIR encoder/decoder. The I²C interface complies with standard-mode (100 kbps) and fast-mode (400 kbps) specifications. No external transceivers are needed for basic operation of any interface. The LM3S1637-IBZ50-A2T does not include USB or Ethernet peripherals.

Is the LM3S1637-IBZ50-A2T pin-compatible with other Stellaris LM3S devices?

No, the LM3S1637-IBZ50-A2T is not universally pin-compatible across the LM3S family. While it shares the 100-pin LQFP package with several variants (e.g., LM3S1968), pin functions differ significantly due to peripheral variations-especially in hibernation, PWM, and analog signal routing. For example, HIB-related pins (HIB, RTCCLK) and comparator inputs are assigned to unique locations not shared with LM3S1138 or LM3S811. Migration requires PCB layout review. The LM3S1637-IBZ50-A2T datasheet (SPMS028I Section 17) defines its exact pinout and must be used for design verification.