Sunday, January 16, 2011
Weak current College】 【electronics engineers to consider minimum cost calculation】.
Minimum cost calculation unit: money in now when prices rose, have already dropped out of currency exchange in the stage of history, becoming the financial sense for the smallest unit of measure. At that time "I picked up at the edge of the road, a" nursery rhyme, does not happen again, money has not been anything.
A penny, has really worthless? let's look, look at the price of electronic materials: an ordinary SMD 0603 resistors 0.29 penny, a capacitor 0603 of 104 1 penny, an SMD 8550 triode 5 cents, a SMD diodes 4148 4.6 penny ... These components are measured in minutes, if measured in dollars, you will see in front of a lot of "0", this years concluded that many of our several materials not value for money.
But you have not thought about another fact: an SMD resistors used after subsequent processing fees is 1.5 penny, a transistor's processing fees is 2.2 penny, the above material becomes an SMD resistors integrated full cost is 1.79 penny, than the resistance itself costs 6 times; a SMD capacitor's comprehensive cost is 2.5 penny, high cost than itself; 2.5 times a SMD transistor integrated cost is 7.2 penny, 1.44 times than their high; a SMD diode integrated cost is 6.1 penny, high cost than itself ... 1.32 times So, do you feel our materials in use, it doesn't seem to save money? I'm here to the next conclusion: don't take a penny of improper thing
Let me slowly to us about a resistor, one capacitor, what was going on. "Just a little money, big things Ah," this point continue to reserve, please see below.
We are a mature hot machine, one year I'll have 10 million sales, some more than this number, we made several assumptions, or the above items. Each machine saves a SMD resistors, we can save you $ 1790; little stick a SMD capacitor, saving $ 2500; delete one SMD transistor, save $ 7200; not a SMD diodes, saving $ 6100, the money, we have the feeling that everyone sees, saving the same item, a few months off, it is your own salary
So, don't take a penny of improper thing, an annual output of 10 million machines easily wasted more of 1 $. How do we approach to money seriously? I have a few suggestions:
1. the design of electronic sources.
If you use good material, the performance is high, you are the high level of electronic engineers? it seems to me that this is spam engineer. True high level, is the most streamlined programme, the cheapest material, to be able to achieve the same performance, or obtain the performance to meet the customer's requirements, here is the key to the selected material. Electronic engineers generally conservative, conservative is a good thing, but a lot of conservative, is built on its own technical level is not high enough. For example, filter capacitors, is not it better? is in theory, but in fact you rarely use a 104 SMD capacitor, system crash? 470uF become 100uF, performance for acceptable? these things, many electronic engineers have not ever even thought about, and few really dig out too, and even dig out, also because seeking stable last in the BOM or use all of the so-called experience parameter.
2, BOM design.
In order to adapt to the needs of many customers, the BOM is done a lot to select optional. Questions arise here, two mutually exclusive features of BOM components, use A function, the function of all material B is not all, delete, clean? a BOM, whether making trouble rarely delete several items? just few delete several items, much better than 1 thousand had to cut the checks only you designers clearly know.
3, PCB design.
Cannot use two-tier Board, do not use a four-storey plate; with cardboard, do not use glass fiber plate; with tooling system with processing, do not use PCB flanges, PCB is very expensive materials, we often design time consider the compatibility of that compatibility, PCB area; then also consider progress, the single-panel design double panel; factory to save money to do a system, requested PCB plus 7MM of retaining Tin ... Want to know what the figure? Word: easy. But this is easy money to buy, how much? a keying plate as 60X30MM, single-Panel double panel, take 3.5 Yuan to buy a convenient, a four-storey plate of retaining more expensive Tin side, one month, the TENs are easy to buy a few thousands of dollars a month, we can make excellent electronic engineers, specialized design single-panel, you can buy a large quantity of tooling system have never got a cent wrong thing, cost savings, not asking us to do many great contribution, can save millions of NT dollars, money money, to think that the money will really become so thing, savings, is another way to create a shortcut to profit, we think, to create a product, increase revenue, more difficult thing Ah; contrast to save several items, the same increase revenue, much easier.
The "cost" embodies the highest of electronic engineers. To do: vampires, tried to think, meditate; cost savings to redundant sheyang, go to the compatibility, product quality can not be changed.