Long story short, I decided to try out a Cheapest PCB Prototype -JLCPCB. Why I call “the Cheapest PCB Prototype .”Because i never experience so cheap price. Viewing the banner first time, I can’t believe the price :$2This is review is about only the Cheapest PCB Prototype service, so point one is that they support both modes.
Cheapest PCB Prototype - JLCPCB Cost
Cost was really good. I also got a stencil, which due to size/weight forced express shipping. for this 100x100mm board, cheapest options not including shipping:
Here is an interesting video about JLCPB board.
The Cheapest PCB Prototype - JLCPCB Quality
So cheap price , how about quality? The quality of the boards I received was very consistent. And quite good overall. There was the occasional light scratch, and a semi-consistent sort of wrinkle in the solder mask, but they are only evident under close inspection, never deep enough to cut through the solder mask. The silkscreen is bold and legible, even under a microscope it's consistent and solid. Compare especially the line around U4 to the rev B board in the middle, whose silkscreen is spotty and hard to read. Routing of the internal cutouts is also quite good (although I intentionally rounded as many corners as I could in this version, after experiencing this in rev B). The square corner cutouts around U3 show the worst, still minor, issue here: one corner has a bit of over-cutting.
Since PCBs are composed of several layers, built up using different processes, it is important that these layers all line up accurately. Several layers PCB fabrication is a very sophisticated process especially when many layers are involved on a small size board.
Earlier the manufacturers of multilayer PCB used mechanical contact methods to alignment layers. Now it is much more easier. With imaging systems it is possible to use cameras to align the layers top to bottom and if imprecision is detected, they can be positioned in order to fit properly.
Now lots of manufacturers are gradually adopting the so called Perfect Test system to achieve a top precision layer alignment. It determines the actual position of each inner sheet to 0.001 inch accuracy. According to test a certain number of prototype printed circuit boards, the test system determines the average design clearance between the pattern and holes that connect the sheets. The results are processed and then when you start the actual production process, the system will have calculated the best alignment and give you high precision multilayer PCB products that you'll be proud of.
The jlcpcb boards have a good layer alignmentThey have silkscreen correctly positioned. The silkscreen alignment issue is evident in the photo above, as well as a close-up of the header area:
Most of boards from jlcpcb we have not seen any kind of silkscreen mis-alignment this bad. I must have been really lucky to encounter such a run.
2. Tight Tolerances
On a cursory visual inspection, these traces seem to be fine — no shorts and there is solder mask over traces that run between the SOIC pads (very important). The site makes electrical testing (E-Test), if there was E-Testing done, opens and shorts between electrical nets would have been checked for using an automated process.
These are the latest batch of boards, and they are different from previous. They have a better quality. The PCB are so clean you can deduct the schematics at glance. holes perfectly aligned, soldermask good alignment on both sides, silkscreen has a small offset
3.Solder Pad to Trace Connections
We know that the asymmetry of a qualified board should be avoided in the trace and connected solder pads
And Traces should start from the center of solder pads and not run through the pads.
When the width of the trace is wider than the pad, the trace should not overlap the pad. The trace width should be reduced at the point of contact as shown in figure 1 . When adjacent pins of fine pitch components need to be connected, the trace should not run directly between the pads. Instead, it should run outside of the row and connect as shown in figure2 .
Figure 1: Connecting the trace and pad when the trace width is larger.
Figure 2: Connecting the adjacent pads of fine pitch components.
See the board from JLCPCB. It designs very well.Trace width is just fine.
The Cheapest PCB Prototype - JLCPCB Shipping I placed the order on 14th August, and the boards arrived at my door on the 23th August. In total it took slightly longer than 9 days for an order to be delivered, but the actual time is going to vary between orders.The PCB production took 2-3 days, as they have promised, but the shipping took a little longer than expected. I placed my first order,their website doesn't show the production or shipping status.I worried about that. Yesterday, i visit and found i can track me order.I prefer this.
Conclusion JLCPCB boards are decent, each one properly routed with no jagged edges, and seem to meet the tight requirements in terms of tracking/spacing, as well as drill holes. My other set of boards has rounded edges, and they routed the edges cleanly too. The competition in PCB Prototype is fierce and in the long run the best quality always wins.Their pricing of the PCBs is chepest for me . I think JLCPCB has a significant advantage: so low price, but good quality. That is why I called JLCPCB "Cheapest PCB Prototype".