The ARM Cortex family is incredibly successful. This comprises a range 32-bit RISC ARM processors that have shipped in the tens of billions of units. They are the most widely used devices in mobile phones and are found in TVs, Laptops and just about other consumer device you care to mention.
Most of the press and publicity focuses on the latest high end ARM processors. When you’re looking for a small processor you tend to think of Microchip PIC or Atmels ATtiny range etc. and not of an ARM Cortex processor. But several manufacturers now offer small cheap ARM Cortex M0 processors that are worth a look.
‘Baby’ ARMs
Heading the list of the smaller, cheaper ARM processors must be NXPs LPC810 which is an ARM Cortex M0 in an 8-pin dip package!
This part is more of a hobbyist part. It’s fun but not the cheapest, coming in around $2.50 for one piece. If you want to play around with it a great place to start is AdaFruit’s
Getting Started with the LPC810
32-bit ARM Cortex M0 processors at less than a dollar!
Of more practical use are the 16 and 20 pin TSSOPs in the same NXP LPC8xx family which have more GPIO and come in at less than a dollar for around 100 pieces.
NXP is not the only manufacturer offering this. Also of note is STMicroelectronics STM32F030x family which also offers an ARM Cortex M0 in a 20-pin TSSOP. You can buy a breakout board for a few dollars on Ebay or about $8 on Amazon.
ST Microelectronics STM32F030F4P6 Minimum System Board
Testing out the STM32F030 STM32F030F4P6 Minimum System Board
Conclusion
It’s incredible to think you can now get a 32-bit ARM Cortex at less than a dollar. Definitely something to consider for future designs!
| Manufacturer | NXP | NXP | NXP | ST Microelectronics |
| ARM Cortex M0 | LPC810M | LPC811M | LPC812M | STM32F030 |
| Pins | 8 | 16 | 20 | 20 |
| Clock Speed | 30 MHz | 30 MHz | 30 MHz | 48 MHz |
| GPIO | 6 | 14 | 18 | 15 |
| Flash | 4 kb | 8 kb | 16 kb | 16 kb |
| SRAM | 1 kb | 2 kb | 4 kb | 4 kb |
| USART | 2 | 2 | 3 | 1 |
| SPI | 1 | 1 | 2 | 1 |
| I2C | 1 | 1 | 1 | 1 |
| ADC | Comparator only | Comparator only | Comparator only | 12-bit (11 channels) |
| Package | 8-DIP | TSSOP16 | TSSOP20 | TSSOP20 |
| Mouser Price (QTY 100) | $2.39 | $0.82 | $0.97 | $0.89 |
Comparison of main specifications