Part Number: SN74LVC1T45
Can u suugest the impedance matching circuit compatible with the SN74LVC1T45. I have two 150R at input and output for dampening.
While measuring the output from custom board using 75ohm BNC to BNC connector i am getting the output as follows:-
The output is bad as frequency is getting increased. So i am suspecting the imepdance mismatching for this.
Can somebody provide any suugestion on this?
150 ohms is probably overkill, 33-50 should do. I would try to measure the signal with active probes with that will have lower capacitance and should provide cleaner looking signals when measuring.
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In reply to Dylan Hubbard:
Thank you for the reply. I will try with suggested resistor values. what about impedace matching circuit?
Regarding the Active probes, in the end application, we use BNC to BNC cable for interfacing. Hence I am testing with BNC to BNC 75ohms cable
In reply to Gavi Siddu:
the BNC cables can add upto 120pF of cap loading. If you have 10x passive probes, it would be ideal too.
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In reply to ShreyasRao:
I did some fine tunig by adding two capacitors pulled ground at input and output(12pf and 15pf). There were some improvents in the waveform, but still some issue on the rising and falling edge of the wavefrom. I need improvemnts on the rising and falling edge of the waveform. Can u suggest anything ?
Can somebody suggest anything?
Refer to this FAQ about impedance matching:
Also, refer to the Design considerations app note:
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