Re: ADP1047 some questions

Hi kevin,

Thanks for the questions.

See the answer below:

1. Current sensing ADC of current loop: Clear description, Gain? What’s the level shift current source? ……{page 12, Figure 7}
   100uA.
2. How to get IL? ……………………………..{page 17, Figure 14}
   IL is the IAC signal measuring from the sense resistor through CS+/CS- pin.
3. We found that the hysteresis of Brown-Out is very poor. How to improve it? …………..{page21, Figure18}
   The hysteresis of Brown-Out is determined by the VIN_ON and VIN_OFF value. Using the GUI to program a larger difference of VIN_ON and VIN_OFF value will solve the issue.
4. How to use small value resistance of current sense Resistor in PFC circuit when using ADP1048 ? (PFC = 1200W)
   The full range of CS+/CS- ADC is 500mV. When the load is full, We suggest the ADC input would be between 300mV ~ 500mV for best performance. This will result in larger power loss. You can use two current transformers to sense the Boost FET current and recfitier diode current separately. The output can be connected directly and fed to CS+/CS- pins.

James