Hi all,
I’m trying to perfect a circuit using a TL431 and a PNP MOSFET to cut off power to, in my drawing, shown as a LED. I’m using two 18650 cells in parallel (3.0-4.2V).
The problem is I can’t seem to get it to work. The TL431 is good from 2.5-36V, but it seems, when it gets down to the lower end of its voltage range it struggles. I tried all kinds of fixes including different resistances and transistors. I’m presently using a TP2104 MOSFET. If I adjust it to come on at say 3.5V it doesn’t turn off at 3V, but rather just gets dim.
I would most welcome any ideas or suggestions.
Thank you.
I’m trying to perfect a circuit using a TL431 and a PNP MOSFET to cut off power to, in my drawing, shown as a LED. I’m using two 18650 cells in parallel (3.0-4.2V).
The problem is I can’t seem to get it to work. The TL431 is good from 2.5-36V, but it seems, when it gets down to the lower end of its voltage range it struggles. I tried all kinds of fixes including different resistances and transistors. I’m presently using a TP2104 MOSFET. If I adjust it to come on at say 3.5V it doesn’t turn off at 3V, but rather just gets dim.
I would most welcome any ideas or suggestions.
Thank you.