Tool/software:
Hi,
I am working on a prototype for a wide input voltage to 5v @ 1A power supply.
I am finding that my prototype fails to regulate when VIn passes below VOut.
Specifications:
In: +4v to +48v
Out: +5v @ 1A
Freq: 407 kHz, Soft Start 2.5ms
WEBENCH Link
Schematic:
Scope Captures:
CH1: VIn
CH2: VOut measured at 30 Ohm load
CH3: HO
| CH4 | Boost Mode (roughly 100-200mV above the mode change threshold) | Buck-Boost Mode (Regulation Failure) |
| COMP |  |
 |
| HS |  |
 |
| LO |  |
 |
| FB |  |
 |
| RAMP |  |
 |
| SS |  |
 |
Please let me know if you need any further information or scope captures.
Best Regards, Brian
