New 8-Bit ATtiny AVR Microcontrollers

Alasdair Allan
2 min readJun 28, 2018

When talking about the Internet of Things the assumption is that Moore’s Law will eventually drive the performance of computing so that connected devices will be TCP/IP all the way down. But this ignores a fundamental truism, that to some it may seem heretical, but amongst others it is just the accepted wisdom. In the embedded space the driving force isn’t speed, it is instead cost. If you’re building a million widgets, shaving even a few pennies off the bill of materials cost isn’t just important, it can be the difference between making a profit, or making a loss.

While it’s simpler easier to program the current batch of high-end Arm microcontrollers, in some cases the cost just isn’t worth while. My own opinion is that there is going to be a place for lower cost microprocessors for a long time to come. Enter the two new 8-bit tinyAVR microcontrollers from Microchip, the ATtiny3217 and ATtiny3216.

The ATtiny817 Xplained Pro development kit. (📷: Microchip)

The new Microchip ATtiny3817 has an internal 20 MHz oscillator, a 16-bit RTC, and 32KB of onboard Flash memory. While the chip has 2×10-bit ADC, alongside an 8-bit DAC. With two ADCs available, one can be used with the included Peripheral Touch Controller (PTC) for capacitive touch signal acquisition, while the other can be dedicated to monitoring other inputs.

“Designed for harsh environments these chips include the Power On Reset (POR), programmable Brownout Detect (BOD), Voltage Level Monitor (VLM) and Windowed Watchdog Timer (WWDT). Additionally, a hardware Cyclic Redundancy Check (CRC) performs autonomous verification of the program memory to ensure that the application runs safely.”

Both the ATtiny3217 and ATtiny3216 are available for volume production, with prices starting at $0.68 per unit in 10,000-unit quantities, half the cost of higher-powered and higher-specified ARM chips. If that higher specification isn’t needed, then that’s a big saving for your bill of materials. Samples can be obtained through normal channels, while the ATtiny3127 Xplained Pro evaluation kit is available for $38.00.