[SOLVED] Help with the information how to built the circuit.

I have a chip (SN75451B).I am trying to understand the function of it so that i can built a circuit which shows the function of it.how to test it?i mean i want to give a Square wave to the input and i want to see the output signal.what are the parameters i should consider?
https://datasheet.octopart.com/SN75451BP-Texas-Instruments-datasheet-150411.pdf

The best test circuit to use is the one in the data sheet in Figure 2.

Are you running a parametric test of just trying to find a use for it? Parametric testing requires sampling equipment fast enough to measure the signal rise and fall times and possibly a special testing jig to ensure the input and output impedance are known and matched.

If you just want to see if it works, the logic table is in the data sheet, all you have to do is treat it as an open-collector driver and give it a suitable load to switch on and off.

Brian.

betwixt said:

The best test circuit to use is the one in the data sheet in Figure 2.

Are you running a parametric test of just trying to find a use for it? Parametric testing requires sampling equipment fast enough to measure the signal rise and fall times and possibly a special testing jig to ensure the input and output impedance are known and matched.

If you just want to see if it works, the logic table is in the data sheet, all you have to do is treat it as an open-collector driver and give it a suitable load to switch on and off.

Brian.

Click to expand...

I kept a signal generator to pin 1 and a POT to pin 2 and a 100 ohm resistor to pin 3 . i am getting waveform at the output even thought the voltage supply is off.. how can i be possible ? is it the noise i am seeing ? but the output wave looks perfect square. i want to this chip to work upto 1Mhz square wave.

Well, it will work at 1MHz but I'm confused by you connecting a pot to pin 2, this is a digital switching device and should be driven by digital signals on pin 1 and pin 2. What are you trying to do by feeding analog signal in to it?

The output you are seeing is probably voltage from the input conducting through the protection diodes to the supply line inside the IC but you shouldn't be driving it with the supply switched off anyway because you risk damaging it.

What is the other end of the 100 Ohm resistor connected to?

Brian.

betwixt said:

Well, it will work at 1MHz but I'm confused by you connecting a pot to pin 2, this is a digital switching device and should be driven by digital signals on pin 1 and pin 2. What are you trying to do by feeding analog signal in to it?

The output you are seeing is probably voltage from the input conducting through the protection diodes to the supply line inside the IC but you shouldn't be driving it with the supply switched off anyway because you risk damaging it.

What is the other end of the 100 Ohm resistor connected to?

Brian.

Click to expand...

100ohm is a pull up resistor connected to the positive voltage.
The POT is so that i can make the chip as voltage comparator.as i told u i am new to work with these .at pin1 i am giving DIGITAL signal (square wave from frequency generator ? am i right ?).

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betwixt said:

Well, it will work at 1MHz but I'm confused by you connecting a pot to pin 2, this is a digital switching device and should be driven by digital signals on pin 1 and pin 2. What are you trying to do by feeding analog signal in to it?

The output you are seeing is probably voltage from the input conducting through the protection diodes to the supply line inside the IC but you shouldn't be driving it with the supply switched off anyway because you risk damaging it.

What is the other end of the 100 Ohm resistor connected to?

Brian.

Click to expand...

100ohm is a pull up resistor connected to the positive voltage.
The POT is so that i can make the chip as voltage comparator.as i told u i am new to work with these .at pin1 i am giving DIGITAL signal (square wave from frequency generator ? am i right ?).can u suggest a proper way to use this ?