ST Microelectronics recently launched a few new members in its STM32H7 MCU family, the STM32H7A3, STM32H7B3, and STM32H7B0 with a huge 1.4 MB of RAM and improved Security and Power Consumption.
Bigger Onchip SRAM
With more SRAM on chip there won’t be latency which wold otherwise be there with external SRAM Chips. Out of 1.4MB, 1MB contigous memory helps store graphics on the chip itself, improving the overall graphic performance significantly.
These are the first parts in H7 series which get Chrom-GRC (Graphics Resource Cutter) a hardware unit that shrinks the frame buffer by up to 20% when using a round display, such as those present on a smartwatch. To save resources, Chrom-GRC discards pixels that won’t be visible due to the shape of the screen.
A new a dual Octo-SPI interface is introduced, It’s high throughput and memory-mapped mode means that external Flash is treated as an internal memory during read operations while the low pin count makes designing a PCB simpler. It is now possible to include both a fast HyperRAM and a Flash storage for better performance, map each of them to their respective Octo-SPI port, and use the available multiplexed mode to limit the number of pins necessary, thus reducing the overall design complexity.
OTFDEC for Improved Security
Traditionally, an encrypted program must reside on the internal memory to prevent it from negatively impacting performances. With OTFDEC, engineers can better protect the IPs they put on their external memory.
Crypto core available on the models with a “B” in their nomenclature now supports the decryption of AES 128 bit data on the fly to prevent any latency during cryptographic operations. Its primary purpose is to allow developers to use encrypted code inside their external memory without incurring any penalty.
New parts offer the lowest power consumption of the entire H7 series MCU with a STOP mode demanding only 32 µA.
The lower power consumption of the new models was partly possible thanks to their single Cortex-M7 at 280 MHz and the presence of a new power supply.
As per ST Micro, the STM32H7A3, STM32H7B3, and STM32H7B0 integrate a new switched-mode power supply on top of the LDO already present in the STM32H7 architecture. The changes in the components’ power management, as well as the lower frequency and multiple architectural optimizations, explain the drastically lower consumption. The SMPS allows for more dynamic control of the electrical current to vastly improve the overall efficiency.
Price is also quite reasonable around 5$-8$ depending on features like Pins, Flash and RAM , etc. For example the STM32H7B3LIH6Q is ~7.49$ and STM32H7B0IBT6 just 5.05$ @ MOQ 10000 Units.
News Source: https://blog.st.com/stm32h7a3-stm32h7b3-stm32h7b0/