STMicroelectronics STM32L100C6U6A

Overview

STM32L100C6U6A 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 targets battery-powered portable instrumentation, smart sensors, and wearable medical devices requiring sub-µA standby current.

For engineers reviewing the STM32L100C6U6A datasheet, STM32L100C6U6A pinout, STM32L100C6U6A application, or STM32L100C6U6A equivalent, key selection criteria include its 0.28 µA Standby mode (2 wakeup pins), 12-bit 1 Msps ADC with up to 24 channels, on-chip step-up converter for LCD bias, and 48-pin UFQFPN package with 42 5V-tolerant I/Os.

Technical Context

The device implements dynamic voltage scaling and multiple low-power modes-Stop (0.44 µA), Standby (0.28 µA), and Low-power Run (10.9 µA)-with <8 µs wakeup latency. Its clock system integrates a 32 kHz RTC oscillator with calibration, 16 MHz HSI, 37 kHz LSI, and a 48 MHz PLL dedicated to USB timing.

Analog subsystem includes two ultra-low-power comparators with window mode and wakeup capability, plus a 12-bit ADC operating down to 1.8 V supply. The LCD controller supports contrast adjustment and blinking, powered by an internal step-up converter eliminating external charge pumps.

Key Specifications

Pinout & Package

STM32L100C6U6A is housed in a 48-pin Ultra-Fine Pitch Quad Flat No-lead (UFQFPN) package measuring 7 mm × 7 mm with 0.5 mm pitch. This RoHS-compliant, thermally enhanced package supports reflow soldering and provides optimized thermal dissipation for continuous low-power operation.

Key Features

Applications

Equivalent & Alternatives

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

Compared with STM32L100C6U6A, STM32L051K8U6 trades LCD/USB for lower active power and smaller footprint, while STM32L412KB adds FPU and memory headroom at the cost of missing integrated display support - making the STM32L100C6U6A optimal for cost-sensitive, display-equipped, battery-operated endpoints.

Availability

STM32L100C6U6A is available at Aetrix Electronics and suitable for portable medical sensors, smart utility meters, industrial wireless sensor nodes, and low-power human interface devices requiring stable component supply throughout product lifecycles.

Supply support for STM32L100C6U6A 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, MEMS, and automotive semiconductors.

The STM32L1 series targets ultra-low-power embedded applications where energy efficiency, integrated peripherals, and long battery life are critical - especially in portable healthcare, smart metering, and IoT edge nodes.

FAQ

What is the maximum operating frequency of the STM32L100C6U6A?

The STM32L100C6U6A achieves a maximum CPU frequency of 32 MHz using its internal 16 MHz HSI oscillator with PLL multiplication or an external crystal up to 24 MHz. Performance is sustained across the full 1.8–3.6 V supply range and –40°C to +85°C temperature range, delivering 1.25 DMIPS/MHz (Dhrystone 2.1).

Does the STM32L100C6U6A support USB without an external crystal?

Yes. The device integrates a 48 MHz PLL dedicated to USB 2.0 full-speed operation, which can be driven by the internal 16 MHz HSI oscillator - eliminating the need for an external 48 MHz crystal or oscillator. This reduces BOM cost and PCB area in portable diagnostic tools and firmware update interfaces.

How many I/O pins are 5V tolerant on the STM32L100C6U6A?

42 of the 48 GPIO pins on the STM32L100C6U6A are 5V tolerant when configured in input, output, or alternate function modes. This allows direct interfacing with legacy 5V logic, industrial sensors, and RS-232 transceivers without level-shifting circuitry - simplifying design in mixed-voltage systems.

What is the purpose of the VLCD pin?

The VLCD pin supplies the LCD segment and common driver circuitry. It is driven by an internal step-up converter capable of generating up to 5.5 V from the main VDD supply (1.8–3.6 V). This eliminates external charge-pump ICs and enables direct driving of 3–5 V LCD panels in compact wearable and metering applications.