Jeongmin Cho, Ian Chapman is correct. Redesigning with CMOS is a great idea, but one that management will not necessarily support. There are three ways to get rid of heat: convection, conduction, and radiation.
You have ruled out forced convection by stipulating that you do not want to use a fan. Conduction works only if you provide a good conductor of heat to something at a lower temperature. Conduction is generally not useful once the product packaging has been designed. Lastly, there is radiation which generally requires a large black surface on the outside of the product to be a good radiator. Of course, there are combinations of these approaches. Heat sinks use radiation to heat the nearby air and natural convection (warm air rises) to produce an air flow through the heat-sink fins. If your management will not let you redesign with CMOS and will not permit fans, external heat sinks, or the like, then they'll have to live with a hot product or none at all. Good luck, Pete > Hello everyone, > > I have designed a PSTN videophone. > But it is very hot because of it's small size. > > I would like to solve the heat problem for our videophone > without any cooling fan. > > What is a best solution for a heat problem ? > > Please send me more information. > > regards, > > --jeongmin > > ---------------------------------------------------------------------------- Peter Van Raalte | Email: [email protected] Compliance Engineer | V-Band Corporation | Phone: 914-789-5117 565 Taxter Road | Elmsford NY 10523 | FAX: 914-347-3432 ---------------------------------------------------------------------------
