the slope of the curve.” There are many uses for this function,
including waveshaping and analog computing. An ordinary amplifier
ideally changes only the amplitude of the input signal. A
differentiator can change the waveform of the input signal, for
example, turning a triangle wave into a square wave. A practical
differentiator cannot be used at just any frequency. There exists a
useful range of differentiation, outside of which the circuit does
not produce the desired effect.
Fiore, Op Amps and Linear Integrated Circuits
Section 10.3, Differentiators
1) LM741
(1) 10 nF actual:__________________
(1) 1.5 nF or 1nF actual:__________________
(1) 10kΩ actual:__________________
(1) 1 kΩ actual:__________________
NOTE: USE 1k for input resistor and 10k for feedback resistor
and .001uf for feedback capacitor
1. The equation for Vout for the circuit Vin * (-2pi f Cin
Rfb).
Calculate the highest usable f (“differentiable”),fhigh1 and
fhigh2. Use 10nF for feedback capacitor, 1k for Rin and 10k for
Rf
These will be the same if 10nF is used for feedback
capacitor.
Record these items in Table 1.
fhigh1=1/2pi Rf Cf
fhigh2=1/2pi Rin Cin
- The Concept Of Differentiation Is Usually Described As Finding The Slope Of The Curve There Are Many Uses For This Fu 1 (85.75 KiB) Viewed 16 times
3. Apply a 1 volt peak sine wave one decade below and then above
fhigh. Observe the output signal. Does the circuit appear to be
differentiating?
4. Apply a 1 volt peak triangle wave one decade below and then
above fhigh. Observe the output signal as Graph 6. Does the circuit
appear to be differentiating?
fhigh1 fhigh2
Table 1
(1) 10k actual: (1) 1 kQ actual: NOTE: USE 1k for input resistor and 10k for feedback resistor and .001uf for feedback capacitor ww 1 k HH .0015 μF V+ = +15 VDC pin 7 V-=-15 VDC pin 4 V out MIH 100 .01 μF + 1. The equation for Vout for the circuit Vin (-2pi f Cin Rfb). Calculate the highest usable f ("differentiable"), fhigh1 and fhigh2. Use 10nF for feedback capacitor, 1k for Rin and 10k for Rf