TI E2E Community
AC/DC and Isolated DC/DC Power
AC/DC and Isolated DC/DC Power Forum
Can anybody explain the function of R6, C1,R8 and R9 in the schematic on Page 4 of sluu421a.pdf?
These components along with diodes D4 and D6 form what is known as a snubber/RCD clamp. Generally there is a lot of ringing at the switch nodes caused by leakage inductance and parasitic capacitance. Without this circuitry this ringing could produce large voltages that could damage the synchronous rectifiers.
Thank you very much for the reply.
Could you please let me know the formulas/equations you used to calculate the snubber values such as the capacitance and resistance?I used some formulas from SMPS books , but I cann't get the same number as those in the schematic.
The theoretical calculations are a starting point based on theoreticals, that does not take into account trace inductance and all parasitic capacitances. In most cases you will have to adjust the snubber in the actual circuit. This is why the values used do not match your exact calculations.
Appreciate it a lot for your reply.
is that possible to let me know what are the equations you used as a start point? I need to reconfigure the circuit and my result is too far from the values in the schematic as a start point.
All content and materials on this site are provided "as is". TI and its respective suppliers and providers of content make no representations about the suitability of these materials for any purpose and disclaim all warranties and conditions with regard to these materials, including but not limited to all implied warranties and conditions of merchantability, fitness for a particular purpose, title and non-infringement of any third party intellectual property right. TI and its respective suppliers and providers of content make no representations about the suitability of these materials for any purpose and disclaim all warranties and conditions with respect to these materials. No license, either express or implied, by estoppel or otherwise, is granted by TI. Use of the information on this site may require a license from a third party, or a license from TI.
TI is a global semiconductor design and manufacturing company. Innovate with 100,000+ analog ICs andembedded processors, along with software, tools and the industry’s largest sales/support staff.