NewsMulti-position switch controlled by amplitude

Multi-position switch controlled by amplitude

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The switches controlled by the amplitude of the input signal are utilized as indicators of the input signal’s level and analysis of the level of input signals and indicator of voltages for power supplies and other such things. They are generally constructed as a line of comparator or bipolar field-effect transistors that are paired along with an input resistance voltage divider.

The switch that follows is built with MOSFET Q1-Q11 2N7000. It is distinguished by a simple design, the capability to expand the number of channels for switching and the existence of non-overlapping switch windows. This feature lets you make use of a multi-position switching device that is controlled by amplitude to be an amplitude-controlled multi-load switch that can be controlled by multiple comparable control panels with just two wires.

The panels are made up of a variety of resistors and switches connected in series and the pins which are unoccupied from the switch are joined together and connected through an control line, to power the device and the pins which aren’t used by the resistors are also linked together and connected through an control line, which connects to input of the Multi-position switch.

The multi-position switch operates according to the following. It feeds the input signals to diode R1 to R6. Through the resistive divider R1-R6 the resistors R7 and R12, control signals are transmitted through the gate of field effect transistors, which regulate the load R13-R18. Parallel to those circuits controlling the output (source-gate) that are connected to transistors the transistors are connected to allow for shunting in a sequential manner of these circuits when the input voltage rises.

In the initial condition, in the absence of any controller voltage then voltage of high-level is observed at the six devices’ outputs nearly equal as the voltage that powers the switch (from six to sixty V).

For the first channels the output voltage decreases close completely to zero. figure 2 is when a voltage ranging from 2.4 through 4.1 V are applied to the switch’s input.

Figure 2 Dynamics of electrical processes (switching output stages) of a multi-position switch when a linearly increasing voltage is applied to its input.

In the second channel the window for switching state can be found in the range of 4.9 through 8.0 V. For the third channel, the range is between 9.5 until 12.8 V and for the fourth between 15.2 up to 21.6 V For the fifth, between 25.3 until 32.7 V, and for the sixth, over 38 V.

Maximum input voltage for the multi-position switch should not exceed higher than 40 V. This means that the maximum voltage that can be applied to transistor gates must not exceed the maximum permissible values for passports (no greater than 20 V).

If you want you wish, the voltage switching ranges of the channels can be adjusted by selecting the value for the resistive divider R1-R6 in input.

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Michal Pukala
Electronics and Telecommunications engineer with Electro-energetics Master degree graduation. Lightning designer experienced engineer. Currently working in IT industry.