Laboratory Manual - King Fahd University of Petroleum and Minerals

1
The output voltage in time domain can be expresses as v
o( t)
vi
( ) d
vi
( to)
RC
This means that the output voltage at time t is given by the initial capacitor voltage plus
the integral of the input signal from start of integration interval, here, t=0. Note that dc
gain is infinity which means any small dc component of v i (t) results in output. In
practice, the op amp will saturates at a voltage close to positive or negative supply
depending on input voltage polarity.
Differentiator:
dvi
( t)
The output voltage in time domain can be expresses as vo
( t)
RC
dt
This means that the output is scaled version of derivative of input voltage. The
differentiator is noise magnifier (i.e. spikes may be produced at output due to sharp
changing in v i (t)).
Difference Amplifier:
This circuit amplifies difference between two input signals. The output voltage can be
expresses as R / R )( v v ) ( R / R )( v ) .
v o
(
2 1 1 2 2 1 2
v1
Voltage to Current Converter:
Such a converter is capable of producing a current into a load that is independent of the
load value and also proportional to the input voltage. It can be shown for the simple
voltage to current converter given in Figure 1 that I out =V i /R regardless of the value of Z L .
Can you prove that?
EQUIPMENTS & COMPONENTS
1. Digital Oscilloscope, Bread Board, Digital Multi-Meter, Signal generator.
2. DC power Supplies of 10V and -10V from the Board.
3. Op amps 741.
4. Resistors: 1kΩ, 2kΩ, 5kΩ, 10kΩ, 100kΩ.
5. Capacitors: 1.5nF, 0.1μF.
t
t
o
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