Email: Password: Remember Me | Create Account (Free)

Back to Subject List

Old thread has been locked -- no new posts accepted in this thread
???
09/07/10 11:12
Read: times


 
Msg Score: +1
 +1 Good Answer/Helpful
#178464 - Killed off by switchers
Responding to: ???'s previous message
5A linear regulators have been killed off by switchers, which is why you are struggling for data. Dropping 12V down to 5V at 5A dissipates 35W (hot, hot, hot), and even 7.5V down to 5V dissipates 12.5W. Managing all that heat is expensive and degrades lifetime. A 90% efficient switcher would only dissipate 2.5W.

List of 21 messages in thread
TopicAuthorDate
LM78H05K Datasheet really exists?            01/01/70 00:00      
   Searching for Datasheets            01/01/70 00:00      
      photo            01/01/70 00:00      
         Yes, that's National Semiconductor            01/01/70 00:00      
            You are right again...            01/01/70 00:00      
               I think the "H" may be because it is 5A isnt it?            01/01/70 00:00      
                  from the days of burning your fingers            01/01/70 00:00      
                      I fail to see a modern design needing that amount...            01/01/70 00:00      
                        qualify            01/01/70 00:00      
                           Still need for power - but varying voltages and low loss            01/01/70 00:00      
                           12V the big favourite in a PC            01/01/70 00:00      
                     Killed off by switchers            01/01/70 00:00      
                        The heat was always a challenge with high-power linears            01/01/70 00:00      
                  Disapointed but clear.            01/01/70 00:00      
                     How so?            01/01/70 00:00      
                     You can make your own ...            01/01/70 00:00      
                        re: You can make your own            01/01/70 00:00      
                           Yes, they did, and those sheets were excellent!            01/01/70 00:00      
   the first mistake            01/01/70 00:00      
   Fairchild was the original manufacturer            01/01/70 00:00      
   these parts are hybrids ... so you can synthesize them            01/01/70 00:00      

Back to Subject List