Texas Instruments LM3S3739-IQC50

Overview

LM3S3739-IQC50 from Texas Instruments is a 32-bit ARM Cortex-M3 microcontroller with 256 KB flash, 64 KB SRAM, integrated hibernation module, 8-channel μDMA, and dual 12-bit ADCs (1 MSPS). It operates at 50 MHz, supports 3.3 V supply, and targets low-power industrial control and sensor interface applications.

For engineers reviewing the LM3S3739-IQC50 datasheet, LM3S3739-IQC50 pinout, LM3S3739-IQC50 application, or LM3S3739-IQC50 equivalent, key selection criteria include hibernation-capable RTC, motor control peripherals (PWM, QEI), UART/SSI/USB interfaces, and Cortex-M3 debug support via JTAG/SWD.

Technical Context

The LM3S3739-IQC50 implements the ARM Cortex-M3 core with Thumb-2 instruction set, NVIC for 64 interrupt sources, and SysTick timer. It integrates a hibernation module with battery-backed RTC and 2 KB SRAM, enabling sub-μA sleep current with wake-up on external event or time match.

Peripherals include two 12-bit ADCs (each with 8-sample sequencer, hardware averaging, internal temperature sensor), eight 32/16-bit GPTMs (supporting PWM, input capture, quadrature encoder), three UARTs (one with IrDA SIR), two SSI modules (SPI/Microwire), and USB 2.0 device controller. All are memory-mapped and accessible via APB bus.

Key Specifications

Pinout & Package

LM3S3739-IQC50 is housed in a 100-pin LQFP (14 mm × 14 mm, 0.5 mm pitch) package with exposed thermal pad. Pin functions are defined per TI SPMS084H datasheet Rev H (July 2014).

Key Features

Applications

Equivalent & Alternatives

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

Compared with TM4C123GH6PM and STM32F103VET6, the LM3S3739-IQC50 uniquely delivers integrated hibernate RTC with battery-backed SRAM and USB device PHY in a single 100-pin LQFP-enabling compact, ultra-low-power designs without external timing or interface components.

Availability

LM3S3739-IQC50 is available at Aetrix Electronics and suitable for industrial motor control, smart sensor nodes, USB HID devices, and PLC I/O modules requiring stable component supply and long-term lifecycle support.

Supply support for LM3S3739-IQC50 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 since 1930.

The Stellaris LM3S series was designed as TI's first ARM-based microcontroller platform targeting cost-sensitive, low-power industrial and automation applications with integrated analog and motor control peripherals.

FAQ

What is the maximum operating frequency of the LM3S3739-IQC50?

The LM3S3739-IQC50 operates at a maximum system clock frequency of 50 MHz, derived from its internal PLL or external crystal oscillator. This frequency applies to both the Cortex-M3 core and all synchronous peripherals including GPIO, UART, SSI, and ADC timing. The device meets this specification across the full industrial temperature range (–40°C to +85°C) and 3.3 V ±10% supply voltage.

Does the LM3S3739-IQC50 support USB device functionality without external components?

Yes, the LM3S3739-IQC50 integrates a full-speed USB 2.0 device controller with an on-chip PHY, enabling direct connection to a USB host using only standard termination resistors and a USB connector. No external transceiver or level shifter is required. The USB interface supports HID, CDC, and MSC classes via TI's StellarisWare USB library.

How does the hibernation module in the LM3S3739-IQC50 retain data during deep sleep?

The LM3S3739-IQC50 hibernation module retains 2 KB of SRAM and maintains RTC calendar/time registers using a separate battery-backed power domain (VBAT). When entering hibernate mode, the main power rails are shut down while VBAT sustains the hibernate logic, RTC oscillator, and backup SRAM-achieving typical current draw below 1 μA.

What ADC features are available on the LM3S3739-IQC50?

The LM3S3739-IQC50 includes two independent 12-bit successive-approximation ADCs, each with an 8-step hardware sequencer, programmable sample rate up to 1 MSPS, internal temperature sensor, and hardware averaging (2–64 samples). Both ADCs support differential input mode and can be triggered by software, timer, or GPIO events.

Is the LM3S3739-IQC50 pin-compatible with other Stellaris LM3S devices?

No, the LM3S3739-IQC50 is not pin-compatible with other LM3S devices-even within the same package size-due to unique peripheral mapping and signal assignment. For example, USB0ID and HIB pins occupy specific locations not shared across the LM3S family. Migration requires PCB redesign and firmware adaptation.