P
Pat Lawler
- Jan 1, 1970
- 0
We are designing a switching power supply for a customer that has
multiple outputs. Due to the tight regulation requirements, all
outputs have their own PWM modulators and control loops.
The customer feels the RF emissions (as measured by CISPR 11) will be
reduced by synchronizing the frequencies of all the converters. I
think synchronizing the PWM sections will make the total power supply
emissions as high as possible (emissions are coherent?).
1) What has been your experience with controlling noise from multiple
switching power supplies? Is synchronizing a good idea?
2) If the supplies are synchronized, would a phase shift between
converters (avoiding simultaneous switching of all converters) help?
Thanks,
---
multiple outputs. Due to the tight regulation requirements, all
outputs have their own PWM modulators and control loops.
The customer feels the RF emissions (as measured by CISPR 11) will be
reduced by synchronizing the frequencies of all the converters. I
think synchronizing the PWM sections will make the total power supply
emissions as high as possible (emissions are coherent?).
1) What has been your experience with controlling noise from multiple
switching power supplies? Is synchronizing a good idea?
2) If the supplies are synchronized, would a phase shift between
converters (avoiding simultaneous switching of all converters) help?
Thanks,
---