On a connector like **broken link removed**, what are the lead functions?
I'm assuming '1' is +Vin, and 2 and 3 are ground. Are 2 and 3 open circuit with respect to each other when the plug is disconnected? Or is it the other way around? I'd like for my micro to detect the loss of DC power connection and shut down other stuff before going into sleep mode. Thanks!
Pin 2 and 3 are shorted with no plug inserted. When plug is inserted 3 is tip and 2 is ring. Either or can be power and ground depending on how you wire the plug. Pin 1 may be for shield, not sure.
The connector shown is a DC-power jack. It contains an automatic switch e.g. to change to internal battery power if no power plug is inserted.
Assuming pin1 is +UB, then pin2 is -UB. Closing the connection pin2 -> pin3 UBatt- will be connected to the circuit. The positive battery terminal will be connected to +UB at all times.
Quote:
The shorting arrangement can put as resistive load across the hot connection killing any unwanted signal pickup.
Sometimes called a 'closed-circuit jack'.