Help to develop final PCB for ARDUINO MICRO PROJECT WITH BLUETOOTH LOW ENERGY

Greetings,

I create my project prototype with arduino micro and adafruit bluetooth low energy device.

Now i need to develop the protype to prduction ( like a small usb device ). i just need Rx, Tx, 3.3 V pin from arduino micro.

i started design with atmega32u4 , usb and BLE by using fritzing ide. I am confused with arduino micro parts like rest, bootloader and other pins. Is there any problem to avoid/ unuse the unwanted pin for my project. Is it work correctly like arduino micro. This is my first pcb design. Please help me to design a final pcb with atmega32u4.

Thank you.

You need a way to put the bootloader onto the Micro. That is usually done by putting an ISP header on the board and using another Arduino as a programmer.

Why not use the Micro as a module stacked on your own board?

nufail:
Now i need to develop the protype to prduction ( like a small usb device )

You're about to take on a very significant project.

John Teel has some resources related to moving from Prototype to Production.
Check out his stuff:

nufail:
. i just need Rx, Tx, 3.3 V pin from arduino micro.

You need more than that.

nufail:
i started design with atmega32u4 , usb and BLE by using fritzing ide.

If you are serious about any level of "production" (more than a few boards), you won't get very far with Fritzing. It might be enough to give a real engineer details they need, but it is pretty limiting it when it comes to "production level."

nufail:
I am confused with arduino micro parts like rest, bootloader and other pins.

What is a rest? You need to understand how those other pins are used. They aren't there just to make the chip bigger.

It wouldn't be hard to combine those 2 into a single card for production.
Micro schematics are posted, if you have the other card schematics and a source for the BLE module (sometimes they are made specifically for a customer) that makes it easy.

There is no problem leaving unused pins on the 32U4 disconnected. In your sketch, set them as inputs with pullup resistor enabled for lower power consumption.

Thanx for your replys: i wana make my final USB device smallest as possible. thats why i asking is it any problem for avoiding reset,bootloader ..etc. which pins are essential for arduino micro production..?
and also i am confuse about which pin in atmega32u4 provoide 3.3 volt ...?

nufail:
Thanx for your replys: i wana make my final USB device smallest as possible. thats why i asking is it any problem for avoiding reset,bootloader ..etc. which pins are essential for arduino micro production..?
and also i am confuse about which pin in atmega32u4 provoide 3.3 volt ...?

The atmega32u4 does not provide 3.3 volts out. The Micro does because it has a 3.3 volt regulator on the board.

I know this because I ptototype with the Micro and look at the schematic which is located here.

@ChrisTenone: is it possible to directly connect 3.3 volt regulator volatge in to ble module ..?
please give me an idea if there is any problem if i avoid the arduino micro reset , bootloader from my production design ..?

nufail:
@ChrisTenone: is it possible to directly connect 3.3 volt regulator volatge in to ble module …?
please give me an idea if there is any problem if i avoid the arduino micro reset , bootloader from my production design …?

Hey. You could do that. Add some capacitors, resistors and diodes, but yeah, why not?

Thanx. what about the bootloader and reset..?

For reset, copy what is done on the Arduino boards without the 16U2 interface chip: Pro Mini, Micro etc.

For the bootloader, you are going to need an ICSP connector on your board to be able to put the bootloader onto the chip. The thru-hole 328P chips can sometimes be ordered with the bootloader already flashed at the factory. I don’t know of any source for bootloaded surface mount chips.