Buffer or Unity Gain Op-Amp
If output impedance of a point is a high value
then connecting another circuit at that point will
load it resulting in malfunction or error. Buffers
are used as interface between circuits. Low
impedance of an output means it can source sink
lot of current, when you need 2 opamps use LF353
or TL072 which are dual opamps.
A non-inv FET input is the best buffer, for
inverting buffer use high R values Using very high
R values like 2.2M or higher requires a glass
epoxy PCB and guard rings around pin 2, 3 to
prevent leakage currents on the PCB reaching the
PINs. Also moisture and dust has to be prevented
by using RTV coating or Varnish. Use 78L05 79L05
for the dual supply required by this circuit.
Vout = -(Vin) for inverting
Vout = Vin for
non-inverting
Interactive Tutorials using Virtual Electronic
Components
This is an Interactive Tutor with Virtual Meters and
Pots, shows how a Unity Gain Buffer Operational
Amplifier works. When no gain is required and you
need to match impedance this can be use. Front end
amps, Sensor amps. Polarity Inversion in Analog
Computing or Signal Conditioning.
Slide the Potentiometers just like you would operate
a Sliding Control. Drag the Knob on Pot to increase
or decrease the resistance. The Resistance is shown
is blue letters and dynamically alters value as you
slide the pot.
The mV Source is varied by just moving mouse pointer
over the two buttons, no clicking. This reduces
finger strain and also you have a long lasting
mouse. The mV buttons are special, the variation
picks up speed if you let the mouse pointer remain
on the button. This is Ramp-up and Ramp-down. This
enables you to set it faster with just two buttons.
Finally you have a DVM a Digital Volt Meter that
just Displays the Voltage at any Point, this readout
value has to be noted down.
Use the "iframe" part in this
Buffer Unity Gain OpAmp xml code
Related Reading
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