Minimalistic AVR Programmer

No external components necessary

Similar projects worth following

I built this AVR ISP using the minimum component configuration: Just an ATmega328P acting as the programmer, and some headers. Not even decoupling capacitors were added, and I have had no problems with my design.

I added some flexibility to enable programming of 3.3V systems from a 5V serial connection, but that's about it.

  • 1 × PCB See Github / OSH Park links
  • 1 × ATmega328P-AU Microprocessors, Microcontrollers, DSPs / ARM, RISC-Based Microcontrollers
  • 1 × ICSP header/socket 2x3 pins
  • 1 × FTDI header/socket 1x6 pins
  • 1 × (270 & 470 Ω resistors) 0805 size, only when programming 3.3V chips

View all 6 components

  • 1
    Step 1

    Solder on the ATmega Microcontroller, the input header (FTDI Serial) and the output header (ICSP). Choose the headers (male/female) that fit your needs.

  • 2
    Step 2

    Connect the solder bridge labeled 'PROG' on the back of the PCB.

    Then burn the ArduinoISP sketch included in the Arduino IDE onto the chip using another programmer attached to the ICSP header.

    After programming, disconnect the 'PROG' solder bridge again.

  • 3
    Step 3

    If you will be programming 5V chips from a 5V FTDI cable:

    Add the VCC-EN jumper and enable it to pass 5V from the FTDI cable to the programmer and the ICSP header (for the chip to be programmed).

    Bridge the 270 ohm solder pads together with a blob of solderand leave the 470 ohm pads empty. The resistors are only necessary when programming 3.3V chips.

    If you will be programming 3.3V chips from a 5V FTDI cable:

    Do NOT add the VCC-EN jumper. Both the programmer itself and the chip to be programmed must be supplied with 3.3V from elsewhere. The programmer will draw its power through the ICSP's VCC pin.

    Add the 270 and 470 ohm resistors to lower the 5V from the FTDI's TX line (going into the ISP's RX line) down to 3.3V. The FTDI is fine with 3.3V on its RX line, so the ISP's TX line does not need level shifting.

View all 5 instructions

Enjoy this project?



Similar Projects

Does this project spark your interest?

Become a member to follow this project and never miss any updates