Main Difference
Before debating about 8 bit and 16 bit microcontroller it is important to understand what is microcontroller. A microcontroller is a single and small chip having integrated circuit, processor core and embedded programmable I/O peripherals. 1 bit to 512 bit are common example of microcontrollers. Here we will discuss about 8 bit and 16 bit microcontroller and their differences.
8 bit Microcontroller
8 bit microcontroller is kind of microcontroller having all characteristics of microcontroller and its data units are mostly 8 bits wide. 8 bits wide means your CPU can use 8 bit data bus or pipe and can access the same size data by a single device instruction. For every cycle of instruction its range is 0 to 255. It requires 20mA current to work. Intel 8008 was the first model having 8 bit micro-controller.
16 bit Microcontroller
16 bit microcontroller is more advanced than 8 bit microcontroller. It is more accurate and precise in performing mathematical and technical tasks. Unlike 8 bit microcontroller it uses 16 bits data bus or pipe for a single instruction. For every cycle of instruction its bit range is extended from 0 to 65,535. As 16 bit controller is two time more than 8 bit controller, it can work on two 16 bit numbers. It requires 10mA current to perform.
Key Differences
- First difference is on price. Although due to improvement in design price comparison between two has been reduced but still 8 bit microcontroller is cheaper than 16 bit microcontroller.
- Having 16 bit microcontroller means 16 bus or pipe to carry on data which is two time more than 8 bit microcontroller.
- Due to large bus 16 bit can perform more efficiently and fast as compare to 16 bit microcontroller.
- In performing mathematical functions, 16 bit microcontroller is more accurate and reliable than 8 bit microcontroller.
- For every cycle of instruction, 8 bit range is 0 to 255 while 16 bit has range of 0 to 65535 for every cycle.
- Although 16 bit microcontroller shows double cycle or clock time than 8 bit but having fast time clock means more energy and power will be required to perform.
- 8 bit microcontroller requires 20 mA current to work, which is two time more than the current requirement of 16 bit microcontroller, which requires 10 mA.
- Input and Output peripherals of 16 bit are more advance than 8 bit microcontroller.
- 8 bit microcontroller shows speed of 12 MIPS at 48 MHz while 16 bit shows maximum 16 MIPS at 32 MHz, two time more than 8 bit microcontroller.