Hi Masoud,
I want to sense under voltage conditions of aircraft grid. The aircraft grid frequency range is between 360Hz to 900Hz. I may use voltage divider and filtering capacitor seen below. Filtered and sensed voltage will be connected to VDD of TPS3840.
Pulled up Reset pin will be connected to microcontroller supplied by 3V3.
VDD voltage of TPS3840 will have at least 50mV ripple. In reality, the voltage ripple of VDD will be higher than 50mV. I try to make the voltage ripple of VDD lower than 200mV.
Moreover, I plan to use open-drain type (TPS3840DL), I need to separate VDD and microcontroller VCC voltage. Reset pin will be pulled up microcontroller VCC voltage, not VDD.
Does TPS3840 work at this design?
Do you recommend better option than TPS3840, if required?
Can you send an application note which has grid UVLO sensing, if there is?
I would prefer using TPS3840DL31 for having 200mV hysteresis. We will have voltage ripple at 720Hz (1.4ms period). Typical tp_HL value of TPS3840DL31 is 15us. So, do you still consider that TPS3840DL is valid option to detect 360Hz to 800Hz AC line UVLO condition?
