STM32F101CBT6 ST Mainstream Arm Cortex-M3 Access Line 32-bit MCU 128KB Flash 36MHz CPU 12-bit ADC LQFP-48

STM32F101CBT6 Product Overview

The STM32F101CBT6 is a mainstream Arm Cortex-M3 access line 32-bit MCU from STMicroelectronics, LQFP-48 package (7×7×1.4 mm). 36 MHz Cortex-M3 core, 1.25 DMIPS/MHz, single-cycle multiplication and hardware division. 128 KB Flash, 16 KB SRAM. Integrates 12-bit ADC (10 channels, 1 µs), temperature sensor, 7-channel DMA (supporting timers, ADC, SPI, I2C, USART), up to 6 timers (3×16-bit GP/IC/OC/PWM/pulse counter, independent/window WDG, 24-bit SysTick), up to 7 communication interfaces (up to 2×I2C/SMBus/PMBus, up to 3×USART/ISO 7816/LIN/IrDA/modem control, up to 2×SPI/18 Mbit/s). 37 I/Os, almost all 5 V-tolerant, mappable on 16 external interrupt vectors. VDD 2.0 V–3.6 V, -40 °C to 85 °C, ECOPACK®2.

STM32F101CBT6 Core Features

Core: Arm Cortex-M3 36 MHz, 1.25 DMIPS/MHz, single-cycle multiplication/hardware division, SWD & JTAG debug Memory: 128 KB Flash, 16 KB SRAM, CRC, 96-bit unique ID 12-bit ADC: 10 channels, 1 µs, 0–3.6 V, temperature sensor 7-ch DMA: Supporting timers, ADC, SPI, I2C, USART Up to 6 Timers: 3×16-bit GP (up to 4 IC/OC/PWM/pulse counter), independent/window WDG, 24-bit SysTick Communication: Up to 2×I2C (SMBus/PMBus), up to 3×USART (ISO 7816/LIN/IrDA/modem control), up to 2×SPI (18 Mbit/s) Low Power: Sleep/Stop/Standby, VBAT for RTC and backup registers Clock: 4–16 MHz XTAL, 32 kHz RTC XTAL (calibrated), 8 MHz RC (factory-trimmed), 40 kHz RC, PLL I/Os: 37 fast I/Os, almost all 5 V-tolerant, mappable on 16 ext. interrupt vectors Supply/Temp: VDD 2.0 V–3.6 V, POR/PDR/PVD, -40 °C to 85 °C Package: LQFP-48 (7×7×1.4 mm), Tray

STM32F101CBT6 Applications

Industrial: PLCs, sensor transmitters, inverters, printers Motor Control: Fans, pumps, small motors (3 GP timers with PWM output) Consumer: Remote controls, handhelds, PC peripherals, GPS platforms, gaming peripherals Medical: Handheld medical terminals Home Appliances: Panels, HVAC, alarms, video intercoms Security: Access control, alarms, smoke detectors IoT: Wireless sensors, environmental monitoring, smart home LED Lighting: Dimming, RGB strips, SMPS

STM32F101CBT6 Key Advantages

Arm Cortex-M3 Core: 36 MHz, 1.25 DMIPS/MHz, single-cycle multiplication/hardware division, far exceeding Cortex-M0 performance at same frequency 128 KB Flash + 16 KB SRAM: For medium-complexity applications LQFP-48 Package: 7×7 mm, 37 I/Os (almost all 5 V-tolerant), balanced package size and I/O resources 12-bit ADC: 1 µs conversion time, 10 channels, temperature sensor, separate analog supply 7-ch DMA: Direct peripheral-to-memory transfers, offloads CPU Up to 7 Communication Interfaces: 2×I2C + 3×USART (ISO 7816/LIN/IrDA/modem control) + 2×SPI (18 Mbit/s), meeting multi-bus connectivity needs 6 Timers: 3×16-bit GP/IC/OC/PWM/pulse counter + independent/window WDG + 24-bit SysTick Calendar RTC: VBAT backup, ideal for scheduled sensing and low-power applications Mature STM32 Ecosystem: CubeIDE/CubeMX/HAL/LL libraries, abundant development boards and reference designs Cost-Effective Access Line: 32-bit ARM + ADC + DMA + rich communication interfaces, ideal upgrade from 8/16-bit MCUs

Why Choose QIXINWEI

Years of experience in the electronics industry. Trusted by global customers.

Massive In-Stock Inventory – Ready to ship promptly

BOM Matching Service – One-stop solution, save time

PCBA Customization – Professional engineering team creates tailor-made solutions based on your needs

Cost-Effective & Efficient – Better channel, better cost

A dedicated team makes your procurement smoother.

Contact us for BOM quotes or PCBA inquiries

FAQ:

1. What is the STM32F101CBT6 and how does it differ from the STM32F103CBT6?
   The STM32F101CBT6 is a 36 MHz Arm Cortex‑M3 microcontroller with 128 KB Flash and 16 KB SRAM, housed in an LQFP‑48 package. It is the “basic” access‑line member of the STM32F1 family, offering essential peripherals at an extremely competitive cost. The key differences from the popular STM32F103CBT6 are: a lower maximum CPU clock (36 MHz vs 72 MHz), no USB interface, no CAN controller, no FSMC external memory bus, and slightly smaller SRAM (16 KB vs 20 KB). This makes the F101CBT6 ideal for simple, cost‑sensitive applications that need a proven 32‑bit core but do not require advanced connectivity or high processing power.

2. Why would I choose the STM32F101CBT6 over an STM32F103 or STM32F407? What are the trade‑offs?
   You choose the F101CBT6 when your design prioritizes low cost and basic processing over speed and advanced features. It sacrifices USB, CAN, FSMC, and DSP/FPU capabilities found on the F103 and F407 series, but in return delivers a very affordable 48‑pin package with plenty of standard serial interfaces (3× USART, 2× SPI, 2× I2C) and a 12‑bit ADC. This is perfect for simple industrial controllers, home appliances, and sensor hubs that only need basic communication and a compact footprint.

3. How does the STM32F101CBT6 compare to the STM32F101RBT6? When should I pick the 48‑pin version?
   Both share the same 36 MHz Cortex‑M3 core, 128 KB Flash, 16 KB SRAM, and identical peripherals (no USB, CAN, or FSMC). The only difference is the package: the CBT6 is an LQFP‑48 with up to 37 I/Os, while the RBT6 is an LQFP‑64 with up to 51 I/Os. Choose the CBT6 when board space is tight and 37 I/Os are sufficient. The RBT6 provides extra I/Os for designs that need more sensors, actuators, or parallel interfaces without moving to a larger board size.

4. Is 128 KB Flash and 16 KB SRAM enough for a real‑time control application without an RTOS?
   Absolutely. For bare‑metal or simple RTOS applications, 128 KB of Flash provides generous space for sensor drivers, communication stacks (USART, SPI, I2C), and control logic. The 16 KB SRAM requires careful buffer management, but using DMA for serial transfers and placing constants in Flash allows many proven designs—such as motor controllers, home automation nodes, and industrial timers—to run comfortably within this memory envelope. If your firmware later outgrows these limits, the pin‑compatible STM32F103CBT6 (72 MHz, 128 KB Flash, 20 KB SRAM) offers a straightforward upgrade path with no PCB changes.

5. Does the STM32F101CBT6 have any USB, CAN, or Ethernet capabilities? How can I add them?
   No, the F101CBT6 does not include a USB peripheral, CAN controller, or Ethernet MAC. If your design needs USB, you must move to the STM32F103 series or use an external SPI‑to‑USB bridge chip. For CAN, you can add an external SPI‑to‑CAN controller such as the MCP2515. If your application absolutely requires built‑in USB and CAN, the pin‑compatible STM32F103CBT6 is a direct upgrade with all these features, at a slightly higher cost.

6. What is the advantage of the 36 MHz clock speed? Does it limit me in any way?
   The 36 MHz clock is deliberately chosen to reduce dynamic power consumption and allow the use of a simple, low‑cost internal RC oscillator without external crystals for many applications. It provides a good balance of processing power for basic control tasks, UART/SPI/I2C communication up to a few Mbps, and ADC sampling. If your application requires fast interrupt response or higher computational throughput, the STM32F103 series (72 MHz) offers double the performance in the same package.

7. What low‑power modes does the STM32F101CBT6 support, and is it suitable for battery‑powered devices?
   The chip supports Sleep, Stop, and Standby modes. In Stop mode with the main regulator off and all 16 KB SRAM retained, the typical current is around 14 µA. Wake‑up from Stop is fast enough to respond to external interrupts. Combined with the lower 36 MHz operating frequency, the F101CBT6 is a solid choice for battery‑powered industrial sensors and portable instruments that spend most of their time in deep sleep and wake up periodically to process and transmit data.

8. Can I perform over‑the‑air (OTA) firmware updates with the 128 KB single‑bank Flash?
   Yes. You can partition the 128 KB Flash into a small bootloader (8–16 KB) and a compact application. The 16 KB SRAM can temporarily buffer the new firmware image received via USART, SPI, or an external wireless module. A CRC check ensures a safe update. An A/B update scheme is not practical with this Flash size; a download‑and‑overwrite approach is recommended.

9. Is the STM32F101CBT6 still a good choice for new designs, or should I move to a newer series like the G0 or G4?
   The F101CBT6 remains a very competitive choice for cost‑sensitive designs that do not require the advanced analog features or higher clock speeds of the STM32G0/G4 series. Its mature F1 ecosystem—HAL/LL libraries, extensive community support, and long‑term availability—dramatically reduces development time. If your design needs a compact footprint with basic serial communication and you want a proven, low‑risk platform, the F101CBT6 is an excellent option. For newer designs that require USB‑PD, advanced ADCs, or ultra‑low power, the STM32G0 or G4 series may be more suitable.

10. What development tools and libraries support the STM32F101CBT6? Is it compatible with the STM32F103 codebase?
    The F101CBT6 is fully supported by STM32CubeIDE, Keil MDK, and IAR EWARM. It uses the same STM32F1 HAL/LL libraries as the F103 series, and almost all code written for the F103 can be directly reused on the F101 as long as you avoid using USB, CAN, FSMC, and respect the lower maximum clock frequency. The Arduino IDE also supports the STM32F101 through the “STM32duino” core, enabling rapid prototyping.