If the power supply to ADG726 is positive ONLY, what is its output voltage level when its input has the positive and the negative wave, such as sine function???
Greetings,
The ADG726 is a multiplexer; basically an analog switch that either connects an input signal to the output or doesn’t.
When the switch is closed, what one puts in is what comes out, so long as what’s going in is between the supply rails provided to the device.
If one tries to apply a voltage outside the limits established by the power supply pins, that signal will either be clamped to about half a volt outside the supply rail or the device will be destroyed, depending on the source impedance of the applied signal.
Sorry, that is what I was asking about.
If the power supply to ADG726 is positive ONLY (+1.8 V to +5.5 V single), this is allowed - specified in the data sheets.
Question: What is its output voltage level when the input signal has both positive and negative levels (Such as sine function)???
Should the output voltage level be lifted to the positive side = sine + DC offset? Or the output level has both positive and negative levels as the input?
The above is not specified in the ADI data sheets.
Yes it is, though you may not recognize it.
Virtually all ICs of this sort internally have diodes between the input(s) and the supply pins to keep applied signals within the limits established by the supplies. Applying a signal outside the boundaries of the supplies causes current to flow through these protection diodes into the supply network.
If that current is kept within reasonable limits (30mA maximum in the above) the device can tolerate it. Failure to respect that limitation will destroy the device.
The same concept applies to the vast majority of ICs on the market, and most datasheets will have an Absolute Maximum section that follows a similar pattern. Most datasheets don’t go to the effort of explaining the matter beyond this, because the idea is so common.
Sorry, that is what I was asking about.
If the power supply to ADG726 is positive ONLY (+1.8 V to +5.5 V single), this is allowed - specified in the data sheets.
Question: What is its output voltage level when the input signal has both positive and negative levels (Such as sine function)???
Should the output voltage level be lifted to the positive side = sine + DC offset? Or the output level has both positive and negative levels as the input?
The above is not specified in the ADI data sheets.
Sorry, you did not answer my question.
If the power supply to ADG726 is positive ONLY (+1.8 V to +5.5 V single), this is allowed - specified in the data sheets.
Question: What is its output voltage level when the input signal has both positive and negative levels (Such as sine function)???
Should the output voltage level be lifted to the positive side = sine + DC offset? Or the output level has both positive and negative levels as the input?
The above is not specified in the ADI data sheets.
From what Rick was saying above.
I would expect that the values that will be seen on either the “DA” or the “DB” pin will end up being restricted to the voltages defined by the power supply you are giving it.
If, say, you are using a 5v+ Vdd and the Vss is connected to GND then when you feed the sine wave into SA1 I would expect that the wave will be clipped / truncated when it tries to go negative and otherwise would provide the positive values for the rest of the signal.
1 Like
Thanks, Nathan.
If that is the case, how can I bring the entire sine wave just above zero level without losing the negative part? Thanks again!
I have found the solution.