hi there,
I have been testing the TL431 in my circuit which latches a relay once the voltage is lower than the set point. I am using a feedback resistor for a hysteresis loop so it gives me a high and low cut off point.
The circuit itself is pretty damn accurate, however when the voltage trips the low set point, the internal resistance seems to bring the battery voltage back up to 12V+ and over the high set point of the hysteresis loop.
This isn't very good as the circuit latches and switches itself back on again. Is there any way to totally cut off the circuit to stop it latching back on again once it has tripped at the low limit?
Another problem with this is that i can't switch on the circuit unless the battery is fully charged/voltage is pulled right up passed the high trip point.
I could do with the circuit being able to manually latch/turn on the circuit at any voltage point and cut off at the low limit and not switch back on until the user switches it off etc.
Any one enlighten me with any more ideas?
I have been testing the TL431 in my circuit which latches a relay once the voltage is lower than the set point. I am using a feedback resistor for a hysteresis loop so it gives me a high and low cut off point.
The circuit itself is pretty damn accurate, however when the voltage trips the low set point, the internal resistance seems to bring the battery voltage back up to 12V+ and over the high set point of the hysteresis loop.
This isn't very good as the circuit latches and switches itself back on again. Is there any way to totally cut off the circuit to stop it latching back on again once it has tripped at the low limit?
Another problem with this is that i can't switch on the circuit unless the battery is fully charged/voltage is pulled right up passed the high trip point.
I could do with the circuit being able to manually latch/turn on the circuit at any voltage point and cut off at the low limit and not switch back on until the user switches it off etc.
Any one enlighten me with any more ideas?
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