The device includes a circuit in parallel with the switch which contains a transistor and {TAIL ~ a diode} to cause such voltage drop in {HEAD ~ the circuit} as to prevent current flowing through a second diode when the switch is closed 
The device includes a circuit in parallel with the switch which contains a transistor and { TAIL ~ a diode } to cause such voltage drop in { HEAD ~ the circuit } as to prevent current flowing through a second diode when the switch is closed
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH