Converting Through the Hole design to partial Surface Mount and ordering assembly services

I am new here and awaiting my first PCB delivery from Aisler.

Where would I go to learn how to make my initial design that is exclusively through the hole parts based to one that incorporates surface mount parts (pushbutton switches, resistors, LEDs, MPU, OLED display) replacing the THT ones I am using now? And then arrange to have that version of the board assembled (parts mounted) before being shipped to me. I used Fritzing software to layout the PCB design that I submitted.

Also, my board has THT for including a specific kind of ESP32 board from a US site (Adafruit). I want to use female pin headers attached to the new board (12 pins on one side, 16 pins on the other) to allow me to plug in the ESP32’s once I have the assembled board in hand.

Is this something that Aisler can support? How do I get started?

Welcome to the community. :grinning:

Aisler can assemble THT and SMD components, assembling THT components however is more expensive than SMD ones. So for smaller runs I would advise to hand solder the THT components.

If you share your design we could assist to find SMD alternatives for you.

Thanks for the reply. What’s the best way to share the design? I have Gerber files and the frtizing software generated project for breadboard, schematic and PCB design.

I posted a new topic about the momentary THT switches that don’t fit my PCB. SMD switches would not have had that problem.

You can create a link on the project page, simply share that.

Looks to me that all of the small components: switches, resistors, LEDs could all be SMD.

There are SMD versions of the MPU6050 and one type of OLED display but I have not prototyped with them (using Arduino IDE) and I would like to verify that they would work for my application.

The ESP32 needs Pin Headers I think to be stable and they would need to be THT as well.

I found this video:

So from my Fritzing design, in the PCB view, I can change the part type from THT to SMD. For some of my parts, there is only one SMD variant (like for the momentary switches). For others like the LEDs and resistors, there are several SMD alternatives. What makes one better than another? Which ones, if added to the BOM, would be cheapest for assembly by Aisler?

I took a look at your design and would recommend to clean it up.
The feather board sticks out of the PCB, the traces are not very well sorted. I brecommend to use a ground plane for easier routing and shorter return paths on your board.

I also suggest to use Kicad for PCB projects, its easy enough to learn quickly but also enables you to make advanced designs later on.

When selecting SMD momentary switches the size and force to press that button are important.
you could sample some SMD switches in various sizes and with different enable forces and see which ones suit your application. Voltage and current rating of the switches are also important.

LEDs are selected based on their forward voltage, current and colour.
Resistors are Selected based on their resistance value and power dissipation.

Your design doesn’t require special considerations in regards to power, thus I would simply select components in a simple to handle size. 1206 ans 0805 are simple to assemble by and or using a assembly machine.

Thanks for continuing to help out.

The overhang of the ESP32 outline is intentional – I will be using rows of header pins.

The traces are all the way they are because of the auto-routing by Fritzing. I know there are good reasons to lay things out by hand but I was curious about the result with auto-routing and while the number of VIAs seems excessive the traces seem to be logically correct.

I have my PCB board sample in hand now and I will solder in the THT components and see if it works.

I am ignorant about ground planes and their use – I did look for an elementary treatment and so far haven’t found a good educational resource.

I will investigate Kicad but the 3-way approach of Fritzing: breadboard, schematic and PCB holds a certain appeal for me.

I was looking for SMD components that Aisler has “on the shelf” and which would help keep assembly costs low. I guess I need to budget for the PCB, a stencil for SMD assembly, the SMD components themselves (from Aisler’s inventory/preferred supplier) and Aisler’s assembly fee. I will look into how to price this out and maybe make an order as an experiment for this kind of work. Can Aisler recommend a specific supplier for the standard sorts of SMD components? Can I just specify a size and perhaps power recommendation and let Aisler do the rest?

Thanks for the size recommendations: 1206 and 0805. I did not know until yesterday that these numbers convey sizing information!!

Your help is much appreciated.

Yes you can Indeed just specify the resistor size and value using the smart match feature and Aisler will handle the rest.

For this you head over to the parts tab, select the resistor and press assign.

Enter the package size and resistance value and let smart match do the rest.

I have converted my Through Hole design to a mixed design with SMD parts selected using the Fritzing software PCB tool. I can only select generic versions for them in the Fritzing interface. I have resistors, single color LEDs and push button switches. I have chosen an 0805 form factor for the resistors and LEDs.

Apparently for Aisler to assemble a board, I need to provide Manufacturer Part Numbers (MPNs). What is the process to follow to find MPNs that Aisler can easily procure to assemble a number of boards for me? I am a novice in all of this. There is a “smart match” process for resistors but nothing for LEDs or momentary push button switches in an SMD form factor. What parts vendor does Aisler have a relationship whose parts catalog might allow me to determine MPNs to include in the BOM?

I was informed by the assembly team at Aisler that Fritzing is no longer a supported design tool to generate a board design that can lead to a board quote that includes assembly.

Disappointing to say the least.

Fritzing is a very limited tool and also has Issues with IPC Netlist and Footprint Missmatches.

If you desire assembly I highly recommend KiCad, its more flexible and capable and easy to learn.

Re: Assigning Parts
You can select basically any part that is available from Mouser, Digikey, Farnell and LCSC. There isnt an limitation to certian vendors.

I did make the conversion from fritzing to KiCad 6 and while it was somewhat of a struggle to get up to speed I was able to convert my design manually and convert the small parts to SMD parts from THT ones. I even used the Manufacturing Part Number (MPN) suggestion to choose the resistors, LEDs and tactile switches to use. I made an Aisler order from the KiCad plugin that included assembly. Wound up being more expensive than I expected.

Estimates are that it will take nearly a month to ship the boards. I ordered 20.