STMicroelectronics STR755FR2H6

Overview

STR755FR2H6 from STMicroelectronics is a 32-bit ARM7TDMI-S™ microcontroller with 256 KB Flash (Bank 0), 16 KB RWW Flash (Bank 1), 16 KB SRAM, integrated USB Full-Speed (12 Mb/s) and CAN 2.0B interfaces, 10-bit ADC (11 channels), 3 UARTs, 2 SSPs, I²C, 6 timers including motor-control PWM with dead-time generation, and support for 3.3V or 5V single-supply operation in LFBGA64 package.

For engineers reviewing the STR755FR2H6 datasheet, STR755FR2H6 pinout, STR755FR2H6 application, or STR755FR2H6 equivalent, this MCU is selected for embedded motor control, industrial communication gateways, and USB-CAN bridge designs requiring deterministic real-time response, dual-protocol connectivity, and on-chip flash data retention up to 20 years at 85°C.

Technical Context

The STR755FR2H6 implements an ARM7TDMI-S core running at up to 60 MHz (54 DMIPS), with a nested interrupt controller supporting 32 vectors and 16 IRQ priorities, and a 4-channel DMA engine servicing UART0, SSP0, PWM timer, TIM0, and ADC. Its clock system integrates a PLL with 4/8 MHz crystal input, internal RC oscillators for fast startup and RTC backup, and dedicated 48 MHz USB clock generation.

It features a Serial Memory Interface (SMI) enabling boot and code execution from external serial Flash (up to 64 MB), memory-mapped access with burst mode (0 wait states @ 60 MHz), and hardware-based Flash protection including readout/write lock. The motor-control PWM timer delivers edge/center-aligned waveforms, 6-channel synchronization, and emergency stop capability - directly targeting brushless DC and induction motor drives.

Key Specifications

Pinout & Package

LFBGA64 (8 × 8 × 1.7 mm, 0.5 mm pitch) package with 38 GPIOs, including high-sink capability (20 mA per pin), atomic bit SET/RES operations, and remappable timer alternate functions. Pin assignments validated per STMicroelectronics Doc ID13593 Rev 5, Section 4.1.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar ARM7-based microcontroller applications.

Compared with STR752FR2H6, STR755FR2H6 adds essential CAN+USB dual connectivity and doubles Flash capacity - critical for field-upgradable industrial gateways. Versus STM32F103C8T6, it retains ARM7 toolchain compatibility and unique RWW+SMI capabilities for secure firmware/data partitioning.

Availability

STR755FR2H6 is available at Aetrix Electronics and suitable for industrial motor drives, USB-CAN protocol bridges, and uninterruptible power supplies requiring stable component supply across extended product lifecycles.

Supply support for STR755FR2H6 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 analog products for industrial, automotive, and consumer markets.

The STR750 family was engineered specifically for industrial embedded control with emphasis on dual-protocol connectivity (USB + CAN), motor-control timing precision, and long-term Flash data integrity - distinguishing it from general-purpose MCUs.

FAQ

Does STR755FR2H6 support simultaneous USB and CAN operation?

Yes, but only in LFBGA64 and LQFP100 packages. In LQFP64, USB and CAN share pins and cannot operate concurrently. The STR755FR2H6 in LFBGA64 package allocates dedicated pins for both interfaces, enabling full-duplex USB device and CAN 2.0B communication simultaneously under 3.3 V supply.

What is the maximum ADC sampling rate achievable with DMA?

With minimum 3.75 µs conversion time and DMA-triggered scan mode, the STR755FR2H6 achieves sustained 11-channel sampling at up to 267 kSPS (100 kSPS per channel in interleaved mode). This is confirmed in Section 6.3.12 of the datasheet and validated using TIM2-triggered ADC start with circular DMA buffer.

How is Flash data retention guaranteed for 20 years at 85°C?

STMicroelectronics specifies 20-year data retention for both Bank 0 (256 KB) and Bank 1 (16 KB RWW) Flash at junction temperature ≤85°C, based on accelerated endurance testing per JESD22-A117. Retention is maintained through oxide charge trapping mitigation and verified write/erase cycling (10k/100k cycles respectively).

Can the internal 48 MHz USB clock be used for other peripherals?

No - the 48 MHz clock derived from the main PLL is hardwired exclusively to the USB module and not routed to the AHB/APB buses. Other peripherals rely on the AHB clock (max 60 MHz) or APB clocks (max 32 MHz), which are independently prescaled from the same PLL output.