Hi All,
I have a circuit in which I'm using the Milone eTape liquid level sensor ( http://milonetech.com/products/chemical-etape-assembly ) with an output as a voltage divider. For it's V+, I'm wanting to use the 4.096VRef of the LM4040AIM3-4.1/NOPB. A circuit diagram is attached.
However, whenever I connect the eTape, the VRef drops to around 3.9v (depending on the resistance of the eTape).
The LM4040 has a current range of up to 15mA and from my calculations, the eTape should only draw up to 1.8mA, so the VRef shouldn't be getting over driven, but I can't work out what's going on.
I need to get a constant and stable VRef into the eTape so that it's readings are relevant.
Any thoughts would be appreciated.
Thanks.
Anubis.
I have a circuit in which I'm using the Milone eTape liquid level sensor ( http://milonetech.com/products/chemical-etape-assembly ) with an output as a voltage divider. For it's V+, I'm wanting to use the 4.096VRef of the LM4040AIM3-4.1/NOPB. A circuit diagram is attached.
However, whenever I connect the eTape, the VRef drops to around 3.9v (depending on the resistance of the eTape).
The LM4040 has a current range of up to 15mA and from my calculations, the eTape should only draw up to 1.8mA, so the VRef shouldn't be getting over driven, but I can't work out what's going on.
I need to get a constant and stable VRef into the eTape so that it's readings are relevant.
Any thoughts would be appreciated.
Thanks.
Anubis.
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