when measuring the signals on the pad

[goatmxj666]

Hello,

I did layout my circuits.

I have a few opamps in my circuit, but when I connected the opamps and pads, I couldn't connect the buffer.

I've heard that when connecting analog signals and pads, it is necessary to connect a buffer.

later when I check the signal at the pads, is the signals would be very strange?

Is there anything else I can do to make the signals a little more accurate when I measuring them on the pads?

I would really appreciate it if you could answer this.

 

[D.A.(Tony)Stewart]

Restate your question with measurable values and images of schematics and signals

 

[goatmxj666]

Restate your question with measurable values and images of schematics and signals

sorry I said it wrong.

actually I didn't connect the buffer between OP AMP and pad when I did the layout.

If I didn't put a buffer in there, is there anything else I can do later when I see the signal through the pad?

Thanks.

 

[D.A.(Tony)Stewart]

How would we know what you are looking at?

 

[dick_freebird]

You might pick a DC divider network that inposes "acceptable"
loading that the op amp output can handle without affecting
the precision care-abouts (like, you don't want to wind up
the input trying to get load current that won't come).

A FET probe can be a low capacitance option for AC stuff
(but tends to be poor for DC).

A close-in JFET-input op amp could be good for a DC buffer,
if you are enterprising and in control of test article assembly
you might even be able to put an op amp die in the cavity
and make your connection(s) a trivial skip-bond, throw the
other op amp pins to package leads and you've got yourself
a hybrid microcircuit. For AC you might prefer another type
of op amp, or maybe find a "do-all" compromise depending
how good your on-chip op amps are expected to be.