1. Operational Amplifier Basics Revision Question 4 An inverting comparator is shown in Figure 4. Calculate the switching threshold voltages and the hysteresis for VREF=+2.5V.

2. Operational Amplifier Basics Revision Question 4 Allow a current to flow from V REF through R1. Since no current can flow into the Op Amp Non-inverting Terminal. The current must continue through the feedback resistor R2 to the output. Let the potential at the Non-inverting terminal be V+. Ideal conditions so the current flowing through R1 equals the current flowing through R2.

3. Operational Amplifier Basics Revision Question 4 When the output voltage is high, the threshold voltage will be given by: Where V H = +5V

4. Operational Amplifier Basics Revision Question 4 Similarly, when the Output Voltage is low, the threshold voltage is given by: Where V L = -5V The hysteresis is given by the difference between V H & V L

5. Operational Amplifier Basics Revision Question 4 Substituting values And