To design and study a diode limiter circuit. 

   Function generator, CRO, resistor, Diode, connecting wires. 

Diode limiter circuit design has been implemented on the virtual breadboard using following specifications:

·         Function generator: Selected wave with following specifications:

Frequency = 100Hz (Any frequency between 50 Hz to 1KHz can be given) 
Wave type: Sinusoidal Wave. 
Amplitude: Varying between 5 to 15 volts. 
Duty cycle = 50% 

·         Resistor R₂:10 K

·         Diode:

The diode limiter also called Clipper as it is used to limit the input voltage. A basic diode limiter circuit is composed of a diode and a resistor. Depending upon the circuit configuration and bias, the circuit may clip or eliminate all or part of an input waveform. 
It limits the output voltage to a specific value. 
The circuit shown in the figure1 illustrates a typical parallel positive and negative limiter circuit. It is called the parallel positive and negative limiter circuit because the diode is in parallel with the output, and the circuit clips or alters the positive and the negative portion of the input waveform. 
The parallel positive and negative limiter is constructed from two diodes in parallel. During the positive alternation, one diode is forward biased. The other diode is forward biased during the negative alteration. 

Figure 1: Parallel Positive and Negative Limiter

1.     Connect the circuit as shown in the circuit diagram.

2.     Give the input signal as specified.

3.     Vary the amplitute of the input signal to verify the voltage limiting of the circuit.

4.     Note down the outputs from the CRO

5.     Draw the necessary waveforms on the graph sheet.

1.     Observe the output waveform from CRO. A sine wave with a high amplitude (Voltage) is clipped.

2.     Measure the amplitude of the output wave from on the CRO screen.

3.     Compare the calculated output voltage with the ecperimentally observerd voltage from the output waveform.

4.     Observe output of the limiter circuit using different input voltage value.

The diode limiter circuit is designed and been studied successfully. 

1.     Connections should be verified before clicking run button.

2.     The resistance to be chosen should be in K ohm range.

3.     Best performance is being obtained with in 50Hz to 1 kHz.