The actual schematic inside this block — every part is explained below.
Op-Amp Amplifier (non-inverting)
Makes a small signal bigger — ×11 here — without loading down whatever produced it.
This is the op-amp circuit: two resistors turn a wildly imprecise amplifier into a
precise one.
U1 — the op-amp. It does exactly one thing: drives its output up or down until
its two inputs match. It has enormous gain (≈10⁶) and terrible precision — and
neither matters, because of the feedback.
R1 + R2 — the gain. They divide the output by 11 and show that to in−. For
the inputs to match, the output must sit at 11× the input. Gain = 1 + R1/R2,
set by a resistor ratio — which is why 1% resistors give you a 1% amplifier from
an op-amp whose own gain varies 10:1 between parts.
The input goes to in+ directly, so the source sees almost no load
(gigaohms) — this circuit amplifies and buffers.
Want a different gain? Change the ratio. Short R1 and delete R2 and you get the
voltage follower — gain of exactly 1, used purely for its high input impedance.
Exposes:vcc, in, out (= 11 × in, within the rails), gnd.
⚠ The output lives between the rails — no further. Gain 11 on a 5 V supply means any
input past ~0.45 V flat-tops. And on a single supply the output can't go below ground
either: a signal that swings negative shows up half-missing until you bias it to
mid-rail. Both look like "broken amplifier"; both are the supply, not the part.
Exposed nets
●vccin · power · 2.7–30 V
●gndin · gnd
●inin · signal
●outout · signal
Inside this block
U1
opamp
the op-amp — it does only one thing: drives its output until in− matches in+. The resistors decide what that means.
R1
100k
feedback — with R2, divides the output by 11 before showing it to in−, so the output must be 11× the input for the inputs to match
R2
10k
bottom of the feedback divider — the gain is 1 + R1/R2; make R2 bigger for less gain, or open it for a follower (gain 1)
Limits & gotchas
⚠gain.note 0 — Gain = 1 + R1/R2 = 11 here. The op-amp itself has a gain near a million — the resistors decide everything, which is the whole point: precision from two cheap parts, not from the amplifier.
⚠rail.note 0 — The output cannot exceed the supply. With gain 11 and VCC = 5 V, any input above ~0.45 V CLIPS at the rail. Size the gain for the largest input you'll ever see, not the typical one.
⚠single-supply.note 0 — On a single supply the output also can't go below 0 V — a signal that swings negative needs a bias to mid-rail (or a split supply). 'My amplifier only shows half the waveform' is this.
Use this block in a real design
Drop it on a canvas, wire it up, and watch the live checks — free, no card.