JLCPCB assembly service
JLCPCB assembly service
JLCPCB assembly (soldering components to the board) service is extremely useful, cheap, and easy to use. I used to fear that it will be difficult and I will screw it up before I have first used it, but the UX is actually great and the flow is very smooth.
Preface
Ordering printed circuit boards online from low-cost services like PCBWay and Seeed Studio is now pretty common among hobbyists and for rapid prototyping. However, once the board arrives, one has to solder all the components — and if 5 or 10 pieces are needed, this is a real pain.
Boards are mass-assembled by pick and place machines and then soldered in a reflow oven. However, up until now, setting this process up required lots of manual intervention and thus was not worth it for less than about 20 to 50 pieces.
The same way PCB manufacturing in small batches has been automated (gerber files from multiple customers are automatically checked and merged into a single giant panel, which is then manufactured), pick-and-place is now automated. From the user standpoint, all that is needed is to visit the parts library and assign a part number to every part in the CAD software. These data, together with the position of these parts on the board, are then exported and uploaded during the ordering process. There are plugins and guides on how to do this with various software, for example KiCad. JLC will automatically add a small fiducial to the corner of the board to facilitate the assembly.
During ordering, both the board (showing various layers — copper, mask, drills…) and the overlay of the placed parts are displayed. Therefore, you can easily check that everything looks right. On the contrary, local Czech fabs such as Printed and PragoBoard are still running on a 1995-style workflow: you send them something via email, talk to some engineers on the phone and you hope for the best. This level of service always surprises me when I need to have a board manufactured by them.
Problems
The only problem I have seen is that some parts are placed 90° or 180° rotated:
- With parts like transistors in SOT-23, there is no common opinion on how the footprint should be placed (horizontally/vertically).
- With some integrated circuits, most notably STM32, the manufacturer claims pin 1 is in the lower left, however, by standard, pin 1 is of course in the upper left.
These problems are visible in the preview and you can simply change the rotation angle in the placement file (it’s a CSV file).
Pricing, delivery, quality
The parts are split into two categories:
- Basic parts. About 700 most common parts (resistors, capacitors, LEDs and basic ICs like voltage regulators and even some stuff like CH340 USB-to-serial, common STM32 and AVR MCUs and SPI flash). They are always loaded in their pick and place machines. You only pay price of the part.
- Extended parts. About 30_000 more parts. Someone needs to fetch then from the storage and load them into the pick and place machine. You pay $3 for the first use.
Additionally, you pay $7 per job (that the panel goes through the assembly line), $1.5 for stencil and $0.0015 per solder joint. Here is an example of a complete board, 5 pieces:
- Board, 100x100mm: $4
- Assembly setup: $7
- Stencil: $1.5
- Components: $5 per board. This includes an AtMega328 MCU, two crystals, a CH340 USB-serial interface, a switching converter, a coil, two FETs, ESD protection and a handful of passives. This is insane, if I were to source these parts locally, it would cost many times more.
- Extended parts fee: $6 (AtMega168 is basic, but we needed an AtMega328)
- Soldering: $3
- Shipping to Prague: $22. Several orders can be combined into one package.
→ $69 total.
The quality of the soldering is good and the quality of the board too. You can see the capabilities here. It actually exceeds standard capabilities of the Czech fabs mentioned above.
Delivery is also insanely fast. It takes 8 calendar days: you place the order on Monday, it is shipped on Thursday and delivered the next Tuesday.
Limitations
The main limitation is that they don’t offer any mechanical and through-hole parts. There are no switches, no connectors, no headers. Therefore, I need to reflow-solder USB connectors by hand, add programming/debug headers and buttons. But it’s still so much better than hand-soldering 100 SMD resistors.
They offer SMD parts down to 0402 size and recently started offering BGA and very cool chips, such as DDR RAMs and entire SoCs. You can literally create a Linux computer on your board now.
Overall, I’d certainly recommend using their service, and we are now using it even for single-shot prototypes.
Originally published at https://www.abclinuxu.cz.
