Dear sir/ madam, We are using LM2842X in one our design. It works well but in order to slow power ramp down rate during power OFF, we need to increase the output capacitor from 22uF to 122uF. Adding more 100uF will be OK for LM2842X or it can arise some issues? Pl advice. As such we need to slow power ramp down rate to have 300 us as minimum time to fall from 2.97V to 2.7V. This is the requirement placed by Maxim serial I2C based RTC to get in battery backup mode. Awaiting your help.
I measured the ramp-up times of 3.3VDC with normal load and full > load >>>> conditions. Ramp-up time with normal load (50mA) is 450us and with full > >>>> load (0.5A) is 650us. >>>> >>>> 1. For normal load case, dV/dt comes to be 7.33mV/us and hence >>>> I=7.33*122=0.894A. >>>> >>>> 2. For full load case, dV/dt comes to be 5.07mV/us and hence >>>> I=5.07*122=0.619A. >>>> >>>> Pl note that I have not added any RC circuit in SHDN pin and values are > >>>> below 1.15A (max current as per datasheet). From our above exercise do >>>> you suggest addition of RC circuit or you think circuit can work well >>>> reliably? Pl advice. >>>> >>>> Awaiting your reply since we need to finalize our design.
-
Ask a related question
What is a related question?A related question is a question created from another question. When the related question is created, it will be automatically linked to the original question.
