| ??? 12/17/05 15:27 Read: times |
#105473 - Power! Responding to: ???'s previous message |
Abhishek Singh said:
if OP can think of connecting 7805 to generate % volts supply and his current requirement are within 7805 operating range, LM317 is an option for sure. @ 30V diffretial its quatient current is just 3 ma. Do you mean quiescent current? If so, quiescent current isn't the issue here - it's the power dissipation from dropping 35V down to 5V with a linear regulator. The 7805 is a 1A regulator, so we could be talking about disipating up to 30W - so you'd have to make sure you chose an appropriate heatsink and package version for the LM317 capable of dissipating that much power! Note that the LM317's power dissipation is internally limited - so you could have all sorts of interesting effects with an underrated package and/or heatsink as the regulator starts shutting itself down...! |
| Topic | Author | Date |
| Add on card programming | 01/01/70 00:00 | |
| please clarify | 01/01/70 00:00 | |
| RE: please clarify | 01/01/70 00:00 | |
| (E)ISA addressing | 01/01/70 00:00 | |
| IOW and IOR | 01/01/70 00:00 | |
| not explicitly | 01/01/70 00:00 | |
| IRQ in EISA slot | 01/01/70 00:00 | |
| interrupt | 01/01/70 00:00 | |
| QBASIC programming | 01/01/70 00:00 | |
| reply | 01/01/70 00:00 | |
| DIP Switch Address Setting in EISA card | 01/01/70 00:00 | |
| DIP switches... | 01/01/70 00:00 | |
| card design enclosed | 01/01/70 00:00 | |
| comparator | 01/01/70 00:00 | |
| QBASIC live and well. | 01/01/70 00:00 | |
| NT - not quite | 01/01/70 00:00 | |
| timing in Win? | 01/01/70 00:00 | |
| QBasic Lives!!! | 01/01/70 00:00 | |
| refer to 'Barry B Brey' | 01/01/70 00:00 | |
| EISA Bus interfacing | 01/01/70 00:00 | |
| beware if (E)ISA bus books | 01/01/70 00:00 | |
| Try this? | 01/01/70 00:00 | |
| Power resistor selection | 01/01/70 00:00 | |
| dont do it | 01/01/70 00:00 | |
| LM317 is an option | 01/01/70 00:00 | |
| Wasteful! | 01/01/70 00:00 | |
| if op can........... | 01/01/70 00:00 | |
| Power! | 01/01/70 00:00 | |
| basic Ohm's law | 01/01/70 00:00 | |
| Trouble shoot | 01/01/70 00:00 | |
| heating | 01/01/70 00:00 | |
| Reply : Heating | 01/01/70 00:00 | |
if you refer to D4 then | 01/01/70 00:00 |