STMicroelectronics STM32L100C6U6ATR

Overview

STM32L100C6U6ATR from STMicroelectronics is an ultra-low-power 32-bit ARM® Cortex®-M3 microcontroller featuring 128 KB Flash, 16 KB SRAM, 2 KB EEPROM with ECC, integrated LCD driver (8×28 segments), USB 2.0 interface, and dual 12-bit DACs. It operates from 1.8 V to 3.6 V across –40°C to +85°C and delivers 1.25 DMIPS/MHz performance-ideal for battery-powered portable medical devices, smart utility meters, and wearable sensors requiring long runtime and on-chip analog integration.

For engineers reviewing the STM32L100C6U6ATR datasheet, STM32L100C6U6ATR pinout, STM32L100C6U6ATR application, or STM32L100C6U6ATR equivalent, key selection criteria include standby current (0.28 µA), LCD segment drive capability, USB 2.0 compliance without external PHY, 12-bit ADC with 24-channel multiplexing, and 51 fast I/Os with 5V tolerance on 42 pins.

Technical Context

The STM32L100C6U6ATR implements a multi-voltage domain architecture with dynamic voltage scaling to optimize power vs. performance. Its clock system integrates six independent sources-including HSE (1–24 MHz), LSE (32.768 kHz), HSI (16 MHz), LSI (37 kHz), MSI (65 kHz–4.2 MHz), and a USB PLL generating 48 MHz-enabling precise low-power mode transitions and RTC calibration.

It features a memory protection unit (MPU), hardware CRC engine, and dual watchdogs (independent + window). Analog subsystem includes two ultra-low-power comparators with wakeup capability, 12-bit ADC (1 Msps, 24 channels), and two buffered 12-bit DACs-all functional down to 1.8 V supply, supporting sensor signal conditioning and display bias control in single-supply systems.

Key Specifications

Pinout & Package

STM32L100C6U6ATR is housed in a 48-pin UFQFPN package (7 × 7 mm, 0.5 mm pitch) with exposed thermal pad, optimized for space-constrained portable designs requiring efficient heat dissipation and low-profile mounting.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar ultra-low-power microcontroller applications.

Compared with STM32L100C6U6ATR, STM32L051K8U6 trades EEPROM and LCD for lower cost and smaller Flash, while STM32L151C8U6 adds security IP and larger memory but retains identical low-power performance and peripheral compatibility-making it a drop-in upgrade path for evolving firmware requirements.

Availability

STM32L100C6U6ATR is available at Aetrix Electronics and suitable for portable medical sensors, smart utility meters, and wearable health trackers requiring stable component supply, long-term lifecycle assurance, and consistent parametric performance across production batches.

Supply support for STM32L100C6U6ATR 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

STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, designing and manufacturing microcontrollers, power management ICs, sensors, and automotive semiconductors since 1987.

The STM32L1 series targets ultra-low-power embedded applications demanding extended battery life, integrated analog functionality, and robust firmware security-designed specifically for portable instrumentation, energy metering, and IoT edge nodes operating under strict energy budgets.

FAQ

What is the maximum operating frequency and corresponding power consumption in Run mode?

The STM32L100C6U6ATR achieves a maximum CPU frequency of 32 MHz. At this speed, typical current consumption is 185 µA/MHz when running code from Flash, resulting in approximately 5.92 mA total. This value assumes VDD = 3.3 V, ambient temperature of 25°C, and all peripherals disabled except core logic.

Does the device support USB device-mode operation without external components?

Yes. The STM32L100C6U6ATR integrates a full-speed USB 2.0 transceiver with internal pull-up resistors and a dedicated 48 MHz PLL. No external PHY, crystal, or termination resistors are required for basic USB device operation-only USB_DP and USB_DM routed to a standard USB connector.

How many I/O pins are 5V tolerant, and what is their safe operating voltage range?

42 of the 51 general-purpose I/O pins are 5V tolerant. These pins accept input voltages up to 5.5 V regardless of VDD level (1.8–3.6 V), enabling direct interfacing with legacy 5V peripherals such as UART transceivers, SPI sensors, or GPIO expanders without level-shifting circuitry.

What LCD configurations does the on-chip controller support, and is external bias required?

The integrated LCD controller supports up to 8 commons and 28 segments (8×28), with programmable contrast, blinking, and internal step-up converter. No external bias generator is needed-the chip provides regulated VLCD output, allowing single-supply operation from the main VDD rail (1.8–3.6 V) for monochrome segment LCDs.