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Atmega328p vs Atmega328- Features, Differences, and Similarities

When buying a microprocessor, you need to go for the particular one that solves your needs. We have prepared this article to help you differentiate between the Atmega328p vsAtmega328 AVR. Check out the features, similarities, differences, and applications of these modules. 

Atmega328p vs. atmega328: Brief overview

Atmega328 5v Arduino Pro Mini Module 16M microcontroller

Figure 1: Atmega328 5v Arduino Pro Mini Module 16M microcontroller

Both are 8bit data processing ICs belonging to the class of Advanced Virtual RISC (AVR) microcontrollers. Also, they have an internal flash memory of 32KBs and an Electrically Erasable Programmable Read-Only Memory (EEPROM) of 1KB. 

Therefore, even if you remove the power supply to the microcontroller, the modules will still store data. Besides, the AVR Atmega328 features a Static Random Access Memory ( 2 KB SRAM). Also, they are both 28-Pin AVR Microcontroller devices made by Microchip. 

Finally, they also feature a 32KB flash type kind of program memory, and both operate on a RISC Architecture. 

Atmega328p vs. atmega328: Pinout

Atmega328p vs. atmega328:ATMEGA 328 Pinout

Fig 2: ATMEGA 328 Pinout

The two belong to the AVR micro-controller category and have 28 pins. Here is a glimpse of each of the pins and their respective functions. 

  1. First, Pin 8 and Pin 22 are the GND pins. They are essential in grounding the circuit. 
  2. Next, Pin 7 and Pin 20 represent the VCC and AVCC pins, respectively. The former is the digital voltage supply pin. Meanwhile, AVCC is the analog to digital converter supply terminal or the alternative power supply pin. 
  3. Pins 14 to 19 and Pins 9 and 10 are Port B pins. They are 8-bit bi-directional I/O port pins with symmetrical drive features. Also, they feature a high sink and a relatively sink capacity. 
  4. Next, Pin 23 to 28 and Pin 1 are Port C pins. They are a 7-bit bi-directional I/O port featuring an internal pull-up resistor. Also, note that Pin 1 functions as an  I/O pin after the programming of the RSTDISBL Fuse. 
  5. Again, we have Pin 2 to Pin 6 and 11 to Pin 13, representing Port D pins. Like Port B pins, they are also 8-bit bi-directional I/O port pins. 
  6. Lastly, we have Pin 21, which is the AREF pin. It is the analog to digital converter’s analog reference pin.

Atmega328p vs atmega328: Block Diagram

Atmega328p vs. atmega328:

Atmega328p vs. atmega328: Memory Size

The ATmega328P- Microchip and the Atmel AVR ATmega328 come with three types of memories. 

  1. First, they have a 32KB flash memory. It is a nonvolatile memory that is also programmable Read-Only Memory (ROM)
  2. Also, they have a 2KB Random Access Memory (RAM), which represents volatile memory. Hence, removing a power supply also erases its data.
  3. Lastly, they feature a 1KB EEPROM

Atmega328p vs. atmega328: The Difference

Atmega328p vs. atmega328:The 328P is better in power consumption

Figure 3: The 328P is better in power consumption

The ATMEGA328P-AUAtmel Corporation buy no remarkable difference from its Atmega328 Micro Controller counterpart. Both ATmega328 plugs have the same architectural look and design. Also, both belong to the 8-Bit AVR Microcontroller Family. 

However, there are several striking differences between the two modules.

  1. For instance, the ATmega328PB- Microchip is more economical in power consumption than the AVR ATmega328. 
  2. Also, the processing power of the 328P is relatively higher than that of its counterpart. Hence, the 328P improves the Nm process, making it a better fit for finer process operations than the 328. 
  3. In addition to being more efficient, the 328P also saves the user remarkable microamps of power. 
  4. Furthermore, they also differ regarding the chip signature. Therefore, you must select the appropriate chip for programming when linking to the Arduino UNO board to ensure compatibility. 
  5. In addition, you’ll only find the TQFP package chip variant in the 328P. Otherwise, you’ll require a finer process to make the 328 fit in a package as small as the TQFP. 
  6. Lastly, the 328 is cheaper in the initial acquisition cost. However, the pricier 328P will save you more as it is economical in power consumption. 


The two microcontrollers are similar in a variety of perspectives. Still, they are different in some respects, as we have elucidated above. Also, for any questions, communicate with us, and we’ll reach back immediately. 

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Emma Lu
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