For most electronics projects, the goal is to get as many well made units out into the world at the lowest cost. Price might not be the top priority, but it is a factor in the success of a device. Particularly in electronics, the economy of scale is taken as a law of nature: the more you produce, the less you pay for production per unit*. This cost structure makes life difficult for small producers, whether they are producing devices for non-commercial ends or are a small company just getting started: the design of a device might be great and the demand real, but the price prohibitive for early adopters at small volumes. The pressure to scale up production runs as quickly as possible can lead to risk taking, sacrifices in quality, and debt, especially when the producer doesn't have enough cash on hand to fund larger production runs.
Is it all worth it? In this post we'll take a look at the pricebreak structure for electronic components at initial production run sizes (100-10k units) and compare with the financial costs to raise enough capital to enable scaling. The BOM (bill of materials) is only one slice of the total price of electronic devices, so a similar analysis would need to be done for costs like PCB fabrication, assembly, quality control, and distribution. Larger organizations often spend as many person-hours on "design for manufacture", sourcing components, and optimizing production as they do on the original device design, and have built up industrial relationships to get special deals over time. This analysis is geared towards projects and organizations without these resources, with the goal of lowering barriers to entry for creative designers and engineers to innovate.
Using Octopart's database of part pricing and availability, we are able to compare the "steepness" of pricebreaks by category. One way to interpret pricing data is to consider the price markup at a given volume compared to the lowest unit price (at the largest volume). For instance, if a distributor sells an IC at $0.14/unit in quantities of 10,000 but at $0.42/unit at quantity 10 and $0.18 at quantity 1,000, then there is a 200% markup at quantity 10 and 29% markup at quantity 1,000. This is a huge difference in price!
The above figure shows price markup curves for hundreds of parts. note that the x-axis (quantity) has logarithmic scale. The coloring indicates the broad category of the part; here we are comparing Microcontrollers, D-Sub connectors, and individual resistors. The first thing that jumps out is that these curves are all over the place; different distributors pursue significantly different "steepnesses" of pricebreaks. In general, the resistors have the highest markups and the microcontrollers have lower markups, but it really depends on the individual part and distributor. Note that most microcontrollers reach almost zero markup at quantity 100, while most connectors and resistors reach low markups around quantities of 1,000. One thing to keep in mind is that many BOMs will have more than one of a given component; if a BOM has 10 identical resistors, then the "per unit" price curves get slid to the left a logarithmic step.
That's interesting, but how do all these pieces contribute to the total price of a device's BOM when parts are sourced aggressively?
This figure shows the per-unit cost markup for an example device which includes a microcontroller, a few connectors, ethernet transceiver, passives, etc. What's happened is that the microcontroller and fancy connectors, which dominate the BOM cost, reach low markups quickly, and the passive components contributing markups all the way up into quantities of thousands make only a small difference to the total unit markup. I'll show the actual figures later, but by a quantity of about 200 the total BOM markup is only 9% over the cost at quantities of 10k. A BOM dominated by through-hole component costs, connectors, or other steep-breaking components might look different and not have this nice niche in the low hundreds, but the total margin at these scales is almost certainly still better than with the single component example mentioned earlier.
Quantity | Total Cost | Base Cost | Base Markup | Kickstarter | Credit Card | Bank Loan |
---|---|---|---|---|---|---|
10 | $277.10 | $27.71 | 81.11% | $30.19 | $30.79 | $28.96 |
100 | $1,718.00 | $17.18 | 12.29% | $18.71 | $19.09 | $17.95 |
175 | $2,929.50 | $16.74 | 9.41% | $18.24 | $18.60 | $17.49 |
500 | $7,975.00 | $15.95 | 4.25% | $17.37 | $17.72 | $16.67 |
1000 | $15,830.00 | $15.83 | 3.46% | $17.24 | $17.59 | $16.54 |
5000 | $76,750.00 | $15.35 | 0.33% | $16.72 | $17.06 | $16.04 |
10000 | $153,000.00 | $15.30 | 0.00% | $16.67 | $17.00 | $15.99 |
The above numbers and specific pricebreaks only cover the BOM portion of a device's total cost: PCB fabrication, testing, and assembly costs can often apply further pressure to scale up production up into the hundreds or thousands, so you'll need to check the numbers for each project individually.
*: Interestingly, this "law" only goes so far: if you scale up production too far you run into higher costs because of the scarcity of resources and inefficiencies in running very large organizations. This means means the cost/scale curve is actually U-shaped; see Wikipedia for more background.