The STM32L433xx devices are the ultra-low-power microcontrollers based on the high-performance Arm® Cortex®-M4 32-bit RISC core operating at a 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 STM32L433xx devices embed high-speed memories (Flash memory up to 256 Kbyte, 64 Kbyte of SRAM), 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 STM32L433xx devices embed several protection mechanisms for embedded Flash memory and SRAM: readout protection, write protection, proprietary code readout protection and Firewall. The devices offer a fast 12-bit ADC (5 Msps), two comparators, one operational amplifier, two DAC channels, an internal voltage reference buffer, a low-power RTC, one general-purpose 32-bit timer, one 16-bit PWM timer dedicated to motor control, four general-purpose 16-bit timers, and two 16-bit low-power timers. In addition, up to 21 capacitive sensing channels are available. The devices also embed an integrated LCD driver 8x40 or 4x44, with internal step-up converter. They also feature standard and advanced communication interfaces. The STM32L433xx operates in the -40 to +85 °C (+105 °C junction), -40 to +105 °C (+125 °C junction) and -40 to +125 °C (+130 °C junction) temperature ranges from a 1.71 to 3.6 V VDD power supply when using internal LDO regulator and a 1.05 to 1.32V VDD12 power supply when using external SMPS supply. A comprehensive set of power-saving modes allows the design of low-power applications. Some independent power supplies are supported: Analogue independent supply input for ADC, DAC, OPAMP and comparators, and 3.3 V dedicated supply input for USB. A VBAT input allows to backup the RTC and backup registers. Dedicated VDD12 power supplies can be used to bypass the internal LDO regulator when connected to an external SMPS. The STM32L433xx family offers eight packages from 48 to 100-pin packages.