Hello there,
I am struggling greatly to design a circuit which operates a solenoid using a touch sensitive switch. The solenoid is of the magnetically latching type which functions in two directions.
The operation should be as follows:
The touch sensor is tripped, activating the solenoid in one direction and power is maintained to the solenoid as long as the touch sensor detects contact.
The touch sensor is released, activating the solenoid in the opposite direction for a short time (10-100ms) and power to the solenoid is subsequently removed.
The circuit must operate on batteries therefore power consumption when inactive must be kept to an absolute minimum. I have 10.5V available from the battery although at present am using a touch sensor which operates at 4.5V. This is not ideal but i can put up with it until i come up with another solution for the sensor ic.
I have virtually no knowledge of electronics and my previous attempts at this have resembled a blind man landing a plane, it all goes fine until the end.
In an attempt to get this working in some regards I have disposed of the power on and timed off functions and temporarily used a mechanical switch for these purposes with the reasoning that it should be straightforward to add at a later date.
The touch sensor i am using is of type QT110 and has an output of 3.6V. I have attempted to use a 4066 CMOS ic to construct a DPDT switch using the output of the sensor chip as a signal however it did dawn on me too late that the output current from this chip would not be sufficient to drive the solenoid (which has 7.6 ? internal resistance and is of 6V rating).
In order to generate alternate signals for the DPDT switch i am using a 4049 inverter ic in order to generate two contrary signals.
In place of the 4066 i subsequently tried a CA3083 5 transistor chip wiring four of these transisors as a DPDT using the signals from the inverter ic. (I fed one signal through two inverters and the other through one in the hope that this would generate signals of approximate voltage.). I haven't yet worket out what is wrong with my second solution, all i know is that the output varies between -0.38V and 0.11V rather than the -10 and 10V output at which i am aiming.
Any suggestions which you feel may help would be greatly appreciated. This really is driving me nuts.
Thanks in advance.
I am struggling greatly to design a circuit which operates a solenoid using a touch sensitive switch. The solenoid is of the magnetically latching type which functions in two directions.
The operation should be as follows:
The touch sensor is tripped, activating the solenoid in one direction and power is maintained to the solenoid as long as the touch sensor detects contact.
The touch sensor is released, activating the solenoid in the opposite direction for a short time (10-100ms) and power to the solenoid is subsequently removed.
The circuit must operate on batteries therefore power consumption when inactive must be kept to an absolute minimum. I have 10.5V available from the battery although at present am using a touch sensor which operates at 4.5V. This is not ideal but i can put up with it until i come up with another solution for the sensor ic.
I have virtually no knowledge of electronics and my previous attempts at this have resembled a blind man landing a plane, it all goes fine until the end.
In an attempt to get this working in some regards I have disposed of the power on and timed off functions and temporarily used a mechanical switch for these purposes with the reasoning that it should be straightforward to add at a later date.
The touch sensor i am using is of type QT110 and has an output of 3.6V. I have attempted to use a 4066 CMOS ic to construct a DPDT switch using the output of the sensor chip as a signal however it did dawn on me too late that the output current from this chip would not be sufficient to drive the solenoid (which has 7.6 ? internal resistance and is of 6V rating).
In order to generate alternate signals for the DPDT switch i am using a 4049 inverter ic in order to generate two contrary signals.
In place of the 4066 i subsequently tried a CA3083 5 transistor chip wiring four of these transisors as a DPDT using the signals from the inverter ic. (I fed one signal through two inverters and the other through one in the hope that this would generate signals of approximate voltage.). I haven't yet worket out what is wrong with my second solution, all i know is that the output varies between -0.38V and 0.11V rather than the -10 and 10V output at which i am aiming.
Any suggestions which you feel may help would be greatly appreciated. This really is driving me nuts.
Thanks in advance.