Construct a 2-to-1 Multiplexer with LT1206 Op-Amp: Step-by-Step Guide & Circuit

MJF23 wrote:

I have 3 op-amp (LT1206) and want to build a 2-to-1-multiplexer. How can I do that?

Hello! I'd be happy to help you build a 2-to-1 multiplexer using your 3 op-amps (LT1206). To start, could you please provide a little more information about the signals you want to multiplex? Specifically, are they analog or digital signals, and what are their voltage levels? Also, do you have a specific control signal (e.g., a logic signal) in mind to select between the two inputs? This information will help me give you a more accurate circuit design.

TM25DN wrote:

The input signals are digital signals, either -5 or +5 V. The selection signal is a digital signal, either 0 or +6 V.

Hello! Thanks for providing the details about your input and selection signals. Based on this information, I can help you design a 2-to-1 digital multiplexer using your LT1206 op-amps.

Here's a simple circuit using two LT1206 op-amps to implement the 2-to-1 digital multiplexer:

1. Comparator (op-amp 1):

- Connect the non-inverting input of op-amp 1 to the selection signal.
- Connect the inverting input of op-amp 1 to a voltage reference at 3V (you can create this reference voltage using a voltage divider or a voltage regulator). This threshold is used to convert the 0 to +6V selection signal to a 0 to +5V logic signal.
- Connect the output of op-amp 1 to the inverting input of op-amp 2.

2. Multiplexer (op-amp 2):

- Connect the non-inverting input of op-amp 2 to the first input signal (signal A).
- Connect a voltage divider to the output of op-amp 2, dividing the output by 2.
- Connect the inverting input of op-amp 3 to the center point of the voltage divider.

3. Multiplexer (op-amp 3):

- Connect the non-inverting input of op-amp 3 to the second input signal (signal B).
- Connect the output of op-amp 3 to the output of your multiplexer circuit.

In this circuit, when the selection signal is 0V, op-amp 1 output will be high (+5V) making op-amp 2 act as a buffer for signal A, while op-amp 3 will be in the inverting configuration, attenuating signal B. When the selection signal is +6V, op-amp 1 output will be low (0V). This will make op-amp 2 in the inverting configuration, attenuating signal A, while op-amp 3 will be a buffer for signal B.

I hope this helps! If you have any questions or need further clarification, please don't hesitate to ask.