Hi,
I'm working on a project using the following capacitive sensing circuit:
http://ics.nxp.com/products/pcf/datasheet/pcf8883.pdf (pg 6, fig 4).
I've tuned this circuit to the particular sensor surface I wish to use, powered by a 9v battery. The output of the circuit I'd like to trigger a relay, so that it breaks the contact of another sensor, which is running on a 12v circuit at 0.02 A.
Firstly, the Limiting value specifications on pg 9 are confusing, it states that output current at max is 50mA, and 9v max, yet total power dissipation is quoted as 100mw, not 450mw?
Secondly, it seems I need a relay that will switch at 8V (allowing a margin for voltage drop) and 30mA that would then have to cope with 12V and 20mA. Can anyone point me in the direction of a suitable one?
Thanks
I'm working on a project using the following capacitive sensing circuit:
http://ics.nxp.com/products/pcf/datasheet/pcf8883.pdf (pg 6, fig 4).
I've tuned this circuit to the particular sensor surface I wish to use, powered by a 9v battery. The output of the circuit I'd like to trigger a relay, so that it breaks the contact of another sensor, which is running on a 12v circuit at 0.02 A.
Firstly, the Limiting value specifications on pg 9 are confusing, it states that output current at max is 50mA, and 9v max, yet total power dissipation is quoted as 100mw, not 450mw?
Secondly, it seems I need a relay that will switch at 8V (allowing a margin for voltage drop) and 30mA that would then have to cope with 12V and 20mA. Can anyone point me in the direction of a suitable one?
Thanks