Timeline for LDO to regulate bootstrap voltage
Current License: CC BY-SA 3.0
12 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| May 3, 2017 at 10:57 | comment | added | Andrew Morton | A 7812 is not an LDO regulator. It is, however, a linear regulator: 7812 minimum input voltage? That doesn't matter for this use, but it is best to use the correct terminology. | |
| May 3, 2017 at 8:52 | answer | added | Velibor Simovic | timeline score: 1 | |
| May 3, 2017 at 8:49 | vote | accept | Velibor Simovic | ||
| May 3, 2017 at 8:44 | comment | added | Andy aka | If you are aware of some and you think they are exotic then I can't add to this. | |
| May 3, 2017 at 8:34 | comment | added | Velibor Simovic | @Andy Can you give an example or two? I am aware that there are some dual/high side drivers, but I would prefer a solution without exotic chips. | |
| May 3, 2017 at 8:30 | comment | added | Andy aka | There are chips from several sources that will do this. | |
| May 3, 2017 at 8:08 | comment | added | Velibor Simovic | @Jodes I wanted to avoid putting zener in parallel due to dissipation. Average current draw of mosfet driver would be somewhat more than 170nC*300kHz = 51mA. If I sized series resistor so as to achieve this current during charging phase of capacitor, once the capacitor is charged, I would have 51mA going through say 15V zener which would cause around 0.7W of losses. That is a bit too much for a normal zener. Plus, consider that series resistor would need to be even smaller because the charging period depends on duty cycle an could amount to less than 20% of the switching period. | |
| May 3, 2017 at 7:43 | answer | added | MCG | timeline score: 1 | |
| May 3, 2017 at 7:41 | comment | added | Bimpelrekkie | f I were to use a 10V zener in series with said diode, the capacitor would be charged to acceptable 24-10 = 14V It might not since there would be very little current flowing once the cap is charged and then the zener will not drop the right voltage but much less. | |
| May 3, 2017 at 7:37 | review | First posts | |||
| May 3, 2017 at 7:39 | |||||
| May 3, 2017 at 7:37 | comment | added | Jayy | A zener in parallel with the capacitor, say 17.5v in the left most diagram to clamp it | |
| May 3, 2017 at 7:33 | history | asked | Velibor Simovic | CC BY-SA 3.0 |