STMicroelectronics STM32F091RCT6

Overview

STM32F091RCT6 from STMicroelectronics is a 32-bit ARM Cortex-M0 microcontroller with 256 KB Flash, 32 KB SRAM, integrated CAN 2.0B interface, dual 12-bit DAC, and 12-bit ADC (1.0 µs conversion) operating at 2.0–3.6 V supply. It delivers up to 48 MHz CPU performance and supports capacitive touch sensing (24 channels), RTC with alarm, and HDMI CEC wakeup-used in industrial HMI panels requiring real-time control, analog signal conditioning, and fieldbus connectivity.

For engineers reviewing the STM32F091RCT6 datasheet, STM32F091RCT6 pinout, STM32F091RCT6 application, or STM32F091RCT6 equivalent, key selection criteria include CAN interface support, 5V-tolerant I/O count (69 pins), 12-bit dual DAC resolution, low-power Stop/Standby modes with RTC retention, and LQFP64 package compatibility for space-constrained PCB layouts.

Technical Context

The device integrates an ARM Cortex-M0 core with hardware parity-protected 32 KB SRAM and 256 KB Flash supporting read-while-write and error correction. Its clock system combines internal oscillators (HSI48 with auto-trimming, 8 MHz HSI, 40 kHz LSI) and external sources (4–32 MHz HSE, 32.768 kHz LSE) feeding a programmable PLL for precise 48 MHz system clock generation.

Peripheral architecture includes two I²C interfaces (one with SMBus/PMBus support), eight USARTs (three with ISO7816/LIN/IrDA), two SPI/I²S modules, one advanced-control timer (TIM1) for 6-channel PWM, and a dedicated touch-sensing controller (TSC) with spread-spectrum modulation for noise immunity in noisy industrial environments.

Key Specifications

Pinout & Package

LQFP64 package: 64-pin quad flat pack, 10 × 10 mm body, 0.5 mm lead pitch, ECOPACK®2 compliant, rated for industrial temperature range (–40°C to +85°C).

Key Features

Applications

Equivalent & Alternatives

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

Compared with STM32F091RCT6, STM32F072RBT6 reduces system cost by omitting CAN and dual DAC but sacrifices fieldbus interoperability; STM32F303RCT6 enhances computational capability with FPU and dual ADCs yet increases BOM complexity and removes integrated touch sensing-making STM32F091RCT6 optimal for CAN-connected HMIs with embedded touch.

Availability

STM32F091RCT6 is available at Aetrix Electronics and suitable for industrial HMI panels, smart building controllers, energy metering nodes, and automated test equipment fixtures requiring stable component supply and long-term manufacturability.

Supply support for STM32F091RCT6 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-grade components since 1987.

The STM32F0 series targets cost-sensitive, low-power industrial and consumer applications, emphasizing analog integration, robustness in harsh environments, and seamless migration within the STM32 ecosystem.

FAQ

Does STM32F091RCT6 support USB device functionality?

No. The STM32F091RCT6 does not include a USB physical layer or USB controller. Pins PA11/PA12 are designated for other alternate functions (e.g., TIM1_CH4, SPI2_NSS) and cannot be used for USB communication. For USB-capable variants, consider STM32F072xx or STM32F042xx families.

What is the maximum operating frequency of the internal HSI48 oscillator?

The internal HSI48 oscillator operates at a nominal 48 MHz with ±2% accuracy over temperature and voltage, and includes automatic trimming against an external clock or USB SOF signal. This allows full-speed operation without an external crystal while maintaining timing compliance for CAN and USART baud rates.

Can the 12-bit DAC outputs drive a 500 Ω load directly?

No. Each DAC channel has a typical output impedance of 15 kΩ and is specified for loads ≥5 kΩ. Driving a 500 Ω load causes significant gain error and settling time degradation. A rail-to-rail op-amp buffer (e.g., TSZ121) is required for low-impedance analog output applications.

How many I/O pins support 5V tolerance on STM32F091RCT6?

Exactly 69 I/O pins are 5V tolerant when VDD is ≥2.0 V. These are distributed across GPIO ports A, B, C, D, E, and F as defined in Section 3.7 of the datasheet. Pins marked "FT" in the pin description table (e.g., PA0–PA15, PB0–PB15) support 5V inputs regardless of VDD level, enabling direct interfacing with 5V logic peripherals.