STMicroelectronics STM32F105RBT6TR

Overview

STM32F105RBT6TR from STMicroelectronics is a 32-bit ARM Cortex-M3 microcontroller in the Connectivity line, featuring 128 KB Flash, 64 KB SRAM, dual CAN 2.0B interfaces, USB OTG FS with on-chip PHY, and 10/100 Ethernet MAC with IEEE 1588 support. It operates at up to 72 MHz, integrates two 12-bit ADCs (16-channel, 1 µs conversion), two 12-bit DACs, and supports industrial automation gateways requiring real-time communication and deterministic I/O control.

For engineers reviewing the STM32F105RBT6TR datasheet, STM32F105RBT6TR pinout, STM32F105RBT6TR application, or STM32F105RBT6TR equivalent, key selection criteria include Ethernet MAC + dual CAN coexistence, USB OTG host/device capability with HNP/SRP, 72 MHz deterministic timing, 51 GPIOs with 5 V tolerance, and LQFP64 package compatibility for space-constrained industrial controllers.

Technical Context

The STM32F105RBT6TR implements a tightly coupled ARM Cortex-M3 core with Harvard bus architecture, single-cycle multiplication, and hardware divide-enabling deterministic 1.25 DMIPS/MHz performance at zero-wait-state Flash access. Its clock system includes dual PLLs (main PLL + dedicated USB/Ethernet PLL), factory-trimmed 8 MHz RC, and 32 kHz RTC oscillator with calibration.

Peripheral interconnect uses AHB/APB2/APB1 buses with remappable I/Os, enabling flexible signal routing for simultaneous Ethernet MII/RMII, dual CAN, and USB OTG without pin conflict. The embedded 4 KB Ethernet SRAM and 512-byte CAN SRAM are physically isolated for low-latency packet buffering and interrupt response.

Key Specifications

Pinout & Package

LQFP64 package (10 × 10 mm, 0.5 mm pitch), RoHS-compliant, operating temperature range –40 °C to +85 °C.

Key Features

Applications

Equivalent & Alternatives

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

Compared with STM32F107VCT6, the STM32F105RBT6TR offers USB OTG host capability in a smaller LQFP64 package but less Flash; versus LPC1788FBD208, it delivers integrated USB PHY and lower system-level BOM cost at the expense of Flash size and extended temperature rating.

Availability

STM32F105RBT6TR is available at Aetrix Electronics and suitable for industrial Ethernet gateways, automotive diagnostic tools, programmable logic controller I/O modules, and USB-to-CAN bridge adapters requiring stable component supply across multi-year production cycles.

Supply support for STM32F105RBT6TR 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 ICs, sensors, and analog components for industrial, automotive, and consumer markets.

The STM32F105xx Connectivity line targets embedded systems requiring simultaneous high-speed wired interfaces-specifically engineered to integrate Ethernet, dual CAN, and USB OTG in resource-constrained industrial edge nodes.

FAQ

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

The STM32F105RBT6TR achieves 72 MHz maximum CPU frequency with typical active current of 42 mA at 3.3 V and 25 °C when executing from Flash with all peripherals enabled. This value scales linearly with voltage and temperature-measured per Section 5.3.5 of DocID15274 Rev 10, Table 13.

Does this MCU support hardware encryption or secure boot features?

No. The STM32F105RBT6TR does not include hardware cryptographic accelerators (AES, SHA, PKA) or tamper-detect circuitry. Secure boot must be implemented in software using external secure elements or trusted execution environments-unlike later STM32F2/F4 series which integrate ART Accelerator and memory protection units.

Can the Ethernet MAC operate in RMII mode with external PHY, and what pins are required?

Yes. The Ethernet MAC supports RMII mode using PA1 (REF_CLK), PA2 (CRS_DV), PA7 (RXD0), PC1 (RXD1), PC4 (TX_EN), PC5 (TXD0), and PB11 (TXD1). External PHY connection requires these seven pins plus VDD/VSS and MDIO/MDC for management interface-fully documented in Section 2.3.20 and Figure 48 of the datasheet.

Is the LQFP64 package pin-compatible with other STM32F105xx variants?

Yes-STM32F105RBT6TR shares identical pinout with STM32F105R8T6 and STM32F105RCT6 in LQFP64. However, Flash size differences (64 KB vs. 128 KB vs. 256 KB) require firmware validation; peripheral enablement (e.g., second CAN) is identical across R-series parts per Table 1 and Section 7 of DocID15274 Rev 10.