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# CALCULATION EQUATION FOR 1 CHIP SOLDERING COST IN SMT PROCESS.

park kyung sam

CALCULATION EQUATION FOR 1 CHIP SOLDERING COST IN SMT PROCESS. | 17 January, 2000

Hi. smtman would someone answer me ? it's just the stuff pop ups without deep thinking. how much do our department spend money for 1 chip soldering. what should i consider ? i wonder i spend more money than other guys out there for 1 chip soldering in smt process. I want to compare the money for mounting one chip among my company and others how come do i calculate the money for one chip mounting. I really want to know that. Maybe someone already has it. Shortly speaking , CALCULATION EQUATION FOR 1 CHIP MOUNTING COST IN SMT PROCESS. Thanks in advance.

Re: CALCULATION EQUATION FOR 1 CHIP SOLDERING COST IN SMT PROCESS. | 17 January, 2000

Cost = Labor + Production Materials + Overhead Cost = Labor * Overhead Multiplier Cost = (Time For Task*Labor Rate*Benefits) * Overhead Multiplier Cost = ((6sec/3600sec/hr)*\$10/hr*1.3) * 2 Cost = \$0.04

park kyung sam

Re: more detail | 19 January, 2000

Would you give me more detail please? i don't understand. is it general in smt process out there or your opinion.

Re: more detail | 19 January, 2000

You said:

"how come do i calculate the money for one chip mounting. I really want to know that. Maybe someone already has it. Shortly speaking , CALCULATION EQUATION FOR 1 CHIP MOUNTING COST IN SMT PROCESS."

So, I gave you equations for calculating that. Providing more detail:

Cost = Labor + Production Materials + Overhead

Labor = (Time To Set-Up + Time For Task) * Labor Rate * Benefits).

Time To Set-Up = Non-recurring time involved in preparing to do a job. Here, I assumed set-up was zero. You could add work instruction preparation and things like that.

Time For Task = Recurring time involved in doing a job. Here, I figured it takes about 6 second to solder a chip component to a board by hand. And, I assumed quality inspection time to be zero.

Labor Rate = Base salary for work performing task. Here, I guessed at \$10 per hour. Your accounting people would know the specific number for your company.

Benefits = Sum of Annual Benefits (ie, vacation, paid sick time and insurance, etc) Costs / Hours Worked Per Year. This should be calculated on a large number of workers. Here, I guessed that these costs were \$3 per hour. Your accounting people would know the specific number for your company.

Production Materials = I assumed this to be zero, but you could calculate the amount of solder used, if you wanted to drill-down for more detail. Here, I also assumed no-clean paste was acceptable.

Overhead = Sum Of The Annual Plant Operating (ie, rent, gas, electric, water, capital costs, salaries and benefits for non-hands-on workers, etc) Costs / Hours Worked Per Year. This should be calculated on a large number of workers. Here, I guessed that this doubled all other costs. Your accounting people would know the specific number for your company.

park kyung sam

thanks | 19 January, 2000

thanks a lot . it will be a big help to me.

Re: thanks | 19 January, 2000

Taking things from a slightly different angle:

Cost of assembling various packages based on volume: C/R placement: |\$0.01 to 0.04 per part SOIC: | \$0.03 PLCC based on lead count: | 20-39 \$0.16 | 40-59 \$0.18 | 60-79 \$0.20 | 80-up \$0.25 BGA | \$0.75 to 3 uBGA | \$1 to 5 Flip chip | \$2 to 5 Chip on board | \$1 to 3

"Circuits Assembly" 11/99 p 52 L Kensen