🚀 go-pugleaf

mark@mips.COM (Mark G. Johnson) writes:
>
>
>Here are the prices of components; minimize the total parts cost:
>   Resistors                      1 cent
>   Capacitors <= 0.5uF            3 cents
>   Capacitors > 0.5uF            15 cents
>   Diodes                         2 cents
>   Zener Diodes                   5 cents
>   Transistors rated < 0.5 Watt   8 cents
>   Transistors rated > 0.5 Watt  20 cents
>   Power MOSFET,     > 0.5 Watt  45 cents
>   Dual Opamp, 0.5 Watt          20 cents
>   Quad Opamp, 0.5 Watt          20 cents
>   Transducer (REQUIRED)        100 cents
>
>(My "solution" costs 152 cents; I suspect it can be done for about 141
> cents by a sufficiently clever design).

-  Are the two opamps really both $.20?
-  What does it mean to call the opamps "0.5 Watt"?
-  What accuracy is required, beyond the low "on" drop specified?
-  If your parts costs are right, and with reasonable accuracy,
   seems like $1.41 might be tough.  (You immediately toss out
   many of the parts as too expensive :-)

BTW, what about the PC board cost?  Connectors?  Mounting/enclosure?
If this were a _real_ problem, an obvious thing to work on is lowering
the cost of the transducer :-).