Dear ADI engineer
The LTC3588 has a 1V hysteresis window, which is very important for energy harvesting. Another PMU(BQ25570), it's hysteresis can be adjusted by the external resistors. I want to realize this function in my application. How is it working? Is there any IC provide this large hysteresis? Or is there any circuit meet this demand?
Yes, while we don't have a part that has the actual hysteresis window configurable by resistors, you might consider LTC3330 which has a few different pin-strapped options:
How it works (which…
How it works (which you could implement externally if you wanted): basically have a comparator with a hysteresis window switching the load on/off. Here's a simple sketch for a comparator with hysteresis:
You might have your supply voltage on one input and a reference voltage on the other. The comparator could drive a P-Channel FET which connects your supply to the energy harvesting circuit.
We do sell nanopower comparators for tasks such as this; you might check out LTC1540.
If you tell me more about your source, I can help you to pick the best approach. There may be no need to solve this with an external regulation solution.
Thank you very much. Actually, my project is rf energy harvesting. Using an antenna to harvest the rf power, an rf to dc circuit charge a storage capacitor. This capacitor is the voltage source. It does not provide a stable voltage. So, if using a comparator, there is no stable voltage can be the reference voltage.
See LTC1540, it is a micropower comparator with an integrated reference voltage, so you do not need to provide the reference.