文档介绍：ST STM32L475Discovery 物联网(IOT) 开发方案 ST 公司的 STM32L475 是超低功耗高性能 MCU, 采用 32 位带 DSP 和浮点单元(FPU) 的 ARM ? Cortex ? -M 4 内核, 工作频率 80MHz, 系列产品提供 256K B到 1M B 闪存, 存储器可采用 SDIO,Quad-SPI 和 FSM C 接口扩展, 并集成了 USB OTG,DFSDM, 提供多达3 个快速12位 ADC, 两个比较器, 两个运放, 两个 DAC 通路, 内部基准电压缓冲器, 低功率 RTC, 两个通用 32 位计时器, 两个用于马达控制的 16 位 PWM 计时器, 七个通用 16 位计时器和两个 16 位低功耗计时器. 主要用在各种低功耗应用如物联网(IoT) 等. 本文介绍了 STM32L475x x 系列主要特性, 框图, 以及时钟树框图,Discovery 开发板 B-L475E IOT01A 主要特性, 框图, 电路图和材料清单. The STM32L475xx devices are the ultra-low-power microcontrollers based on the high-performance ARM ? Cortex ? -M4 32-bit RISC core operating ata frequency of up to 80 MHz. The Cortex-M4 core features a Floating point unit (FPU) single precision which supports all ARM single-precision data-processing instructions and data types. It also implements a full set of DSP instructions and a memory protection unit (MPU) which enhances application security. The STM32L475xx devices embed high-speed memories (Flash memory up to1 Mbyte, up to 128 Kbyte of SRAM), a flexible external memory controller (FSMC) for static memories (for devices with 100 pins package), a Quad SPI flash memories interface (available on all packages) and an extensive range of enhanced I/Os and peripherals connected to two APB buses, two AHB buses and a 32-bit multi-AHB bus matrix. The STM32L475xx devices embed several protection mechanisms for embedded Flash memory and SRAM: readout protection, write protection, proprietary code readout protection and Firewall. The devices offer up to three fast 12-bit ADCs (5 Msps), parators, two operational amp lifi ers, two DAC channels, an internal voltage reference buffer, a low-power RTC, two general-purpose 32-bit timer, two 16-bit PWM timers dedicated to motor control, seven general-purpose 16-bit timers, and two 16-bit low-power timers. The devices support four digital filters for external sigma delta modulators (DFSDM). In addition, up to 21 capacitive sensing channels are available. They also feature standard and municat