| ??? 04/11/06 18:58 Read: times |
#114111 - You are righ Kai. I didnt analyse this w Responding to: ???'s previous message |
Kai Said:
If you want 24V at 1A, for instance, your transformer must additionally deliver more than 2A!! You are righ Kai. I didnt analyse this way. Just thought i would consume 2A totally (1A each from 24V and 5V) from the Transformer. So, selected a transformer with 3A. So thanks for that valuable information. and, what you have said have made me think like this. I require 24V at 1A = 24VA So when 12V rectified o/p is stepped up the same 24VA power would be drawn, leading to increase in rating of the Transformer. Did i got that right? Kai Said: (I just realized, that Suresh isn't needing a 12V supply voltage at all.) Yes. Secondly, the LM2675 option seems to be a nice one when planning to step down. But i thnk it would also dissipate the same power as that a 7805 do, since it has to power the micro continuously (referring my project) and there would be no switching 'OFF' of 2675 in between. Erik Said: why not use one with two outputs ? Seems to be an another nice option. Thank you Suresh. |
| Topic | Author | Date |
| step up voltage regulator | 01/01/70 00:00 | |
| 12V rectified output? | 01/01/70 00:00 | |
| additional Transformer occupies space | 01/01/70 00:00 | |
| 18V Center Tap Transformer? | 01/01/70 00:00 | |
| size ? | 01/01/70 00:00 | |
| Mistake in analysis | 01/01/70 00:00 | |
| why two? | 01/01/70 00:00 | |
| Of course! | 01/01/70 00:00 | |
| easier | 01/01/70 00:00 | |
| You are righ Kai. I didnt analyse this w | 01/01/70 00:00 | |
| nope, that is why it is called a switche | 01/01/70 00:00 | |
| Step-up, step-down | 01/01/70 00:00 | |
| ON/OFF(active low) pin? | 01/01/70 00:00 | |
| Shutdown pin | 01/01/70 00:00 | |
Thanks. | 01/01/70 00:00 | |
| Try this simple circuit. It might work | 01/01/70 00:00 | |
| LM2577 | 01/01/70 00:00 | |
| expensive is relative | 01/01/70 00:00 | |
| Charge pump | 01/01/70 00:00 | |
| Thank you all | 01/01/70 00:00 | |
| Two are needed! | 01/01/70 00:00 |