this presentation is based on basic description of inverting and non-inverting amplifiers using op-amps and their medical use, hope it helps students :)

1. Inverting amplifier (gain 100) and
Non-Inverting amplifier (gain 100)
Presentation by : 16BM02 (M.Mohsin Memon)
Student of Mehran UET, Jamshoro

2. Inverting Amplifiers:
Introduction
A basic op-amp circuit is one
that produces an 180 signal
phase shift, The inverting
amplifier is the op-amp
counterpart of common
emitter and common-source
amplifiers.

3. In Inverting Amplifier circuit the
operational amplifier is connected with
feedback to produce a closed loop
operation. When dealing with
operational amplifiers there are two
very important rules to remember about
inverting amplifiers, these are:
1 “No current flows into the input
terminal”
2“V1 always equals V2”.
However, in real world op-amp circuits
both of these rules are slightly broken.

4. Mathematical modelling of Inverting Amplifier:
Vin is give as
Vin = iinRin
Vout is given as;
Vout = iinRf
Voltage gain;
Av = Vout /Vin
Since Vin = iinRin and Vout = iinRf :
Av = iinRf / iinRin
And then
Av = Rf / Rin
(Rf)
(Rin)

5. Simulation for inverting amplifier (gain 100)

6. Non inverting amplifiers
Introduction:
Non inverting amplifiers have almost
same properties as that of inverting with
following two exceptions:
1. Has much higher input impedance
2. Doesn’t produce 1800 voltage phase
shift

7. There is a slight Change in schematic as
compared to that of inverting amplifiers as
shown in figure below
1 signal is applied to non inverting op-amp
input.
2 input resistor is returned o ground.

8. Mathematical modelling:
Input voltage is given as
Vin = iin Rin ……….. 1
Since the voltage across Rf is equal to the difference
between vin and vout and if =iin, we can state the
current through the resistor is found as
If = Vout – Vin /Rf
And
Vout = iinRf + Vin ……. 2
From the above equations 1 and 2 , we can establish
that
ACL = Rf / Rin + 1

11. Applications of operational amplifiers In
Medical Instrumentation
The zero-drift, rail-to-rail op amps enable a new generation of
portable medical devices. Packaged in 6-pin SC70 (single) and 8-pin
SC70 (dual) packages, the devices claim outstanding precision and
low-noise performance and very small solution size.
Medical examples that use such op amps are:
1. Pulse oximetry
2. E.C.G
3. E.E.G
4. Bio potential amplifiers

12. Thank you ,
Open for Q and A session 
16BM02
Muhamad Mohsin Memon