Cortex-M4 Delivers 210 DMIPS Using 0-wait Memory

Sept. 29, 2011
STmicroelectronics' STM32 F4 series delivers 210 DMIPS using 0-wait state flash memory for the Cortex-M4 processor.

STM32 F4 Cortex-M4

ART Accelerator

STMicroelectronics' 168 MHz STM32 F4 series delivers 210 DMIPS using 0-wait state flash memory for the Cortex-M4 floating point processor (Fig. 1). This is possible because of the ART (adaptive real time) Accelerator (Fig. 2). ART is essentially a single level cache based on 256 128-bit entries. It also has an 8 entry data cache.

ART Accelerator only caches the first 128-bit word of a sequential code sequence because once this word is used the next sequential word can be fetched from the flash memory that does not run fast enough to provide 0-wait state operation. The Cortex-M4 runs 16-bit or 32-bit instructions so the 128-bit word holds at least four instructions. TheF4 series has up to 1 Mbyte of flash. The 192 Kbytes of RAM is split allowing simultaneous access to 16 Kbytes and a 112 Kbyte block. There is also 528 bytes of OTP (one time programmable) memory. The off-chip memory controller handles Compact Flash, SRAM, PSRAM, NAND and NOR flash.

The chip uses very little power. It uses 38.6 mA or 230 uA/MHz running at full speed. It only needs 1uA to run the real time clock (RTC). The chip requires 1.7V to 3.6V DC.

In addition to floating point, the Cortex-M4 core adds DSP instructions that take advantage of the single cycle MAC and barrel shifter. There is on-chip cryptography support for AES 128, 192, 256, Triple DES, plus MD5 and SHA-1 hash.

Communication includes support for a variety of SPI, I2C and UARTs plus I2S support. High speed interfaces include 10/100 Ethernet, USB with OTG support plus a pair of CAN 2.0b interfaces. The SDIO interface provides MMC support. DMA and GPIO are available as well. There is a 54 Mbyte/s 8- to 14-bit parallel camera interface.

On the analog side there is up to three 12-bit, 2.4 Msample/s ADC. These support up to 24 channels and 7.2 Msamples/s in triple interleaved mode. There are two 12-bit DACs converters

The chips are available in LQFP packages as well as a 10mm by 10mm BGA.The F4 is compatible with the L1, F1, and F2 series. The L1 series is an even lower power Cortex-M3 chip. STMicroelectronics has a number of evaluation kits available. The $349 STM3240G-EVAL board provides the most extensive support. The low cost $14.90 STM32F4DISCOVERY provides access to there I/O pins and includes an on-board USB-based debugger.

Sponsored Recommendations

TTI Transportation Resource Center

April 8, 2024
From sensors to vehicle electrification, from design to production, on-board and off-board a TTI Transportation Specialist will help you keep moving into the future. TTI has been...

Cornell Dubilier: Push EV Charging to Higher Productivity and Lower Recharge Times

April 8, 2024
Optimized for high efficiency power inverter/converter level 3 EV charging systems, CDE capacitors offer high capacitance values, low inductance (< 5 nH), high ripple current ...

TTI Hybrid & Electric Vehicles Line Card

April 8, 2024
Components for Infrastructure, Connectivity and On-board Systems TTI stocks the premier electrical components that hybrid and electric vehicle manufacturers and suppliers need...

Bourns: Automotive-Grade Components for the Rough Road Ahead

April 8, 2024
The electronics needed for transportation today is getting increasingly more demanding and sophisticated, requiring not only high quality components but those that interface well...


To join the conversation, and become an exclusive member of Electronic Design, create an account today!