Lab Report 4 - Armen M

4. If the diode is open in the circuit, the load voltage is? 5. If the resistor is ungrounded in the circuit, the voltage measured with a DMM between the top of the resistor and ground is closest to? 6. The load voltage measures 12 V in the circuit. The trouble may be? 7. Using the third approximation in the circuit, how low must R, be before the diode's bulk resistance must be considered? + Vs RL 1 k2 12 V Figure

Consider the following circuit diagram. Using practical diode model solve the following items. i. What is the type of rectification in this circuit? ii. Calculate the total peak secondary voltage (Note that “RMS" value is given in the circuit) iii. Sketch the plot of time vs voltage over Load (RL) iv. Find the average voltage over Load. v. Find the maximum current passing over diodes. vi. Find the peak inverse voltage (PIV) over the diodes. vii. Find the minimum fuse current rating for the primary coil. 5:1 D DA 120 V rms D3 D2 RL=10kQ RL out ell lelll

Briefly discuss the difference between Diode Piecewise-linear model, Simplified model, and Ideal device/ equivalent circuit.  Study the diode specification sheets of a 1N4001 and 1N5401 diodes provided by the manufacturer and compare their difference. Give typical application of each. Discuss briefly how to test junction diode.

5) The figure below illustrates a simple voltage threshold detection circuit. To understand how it operates, we will analyze its behavior based on the simple constant voltage drop model for both diodes. Assume the Zener diode (Z1) only conducts when its breakdown voltage of 10V is reached. Di is a red light emitting diode (LED). Assume it conducts after its forward bias voltage of 1.8V is reached. Vin is unknown. Assume Zj acts as a perfect Zener diode (without series resistance). What voltage does Vin have to reach before there is a current through R¡? What voltage must Vin reach before current flows through R2? Write an equation for the current through Zi in terms of Vin, Rị and R2 that is valid when Vin is high enough for both diodes to be conducting. a. b. c. R2 Vino R1 LED

Consider the circuit shown below. A string of four identical diodes is used so that Vo = 2.8V when IL = 0, and Vo changes by 16 mV per 1mA of load current. Assume n=1.7. (i) Find the small signal (incremental) resistance rd for each diode. (ii) Find the value of R.

Please find the correct answer by solving the problem

a) Use the diode’s characteristic equation,ID=Is exp(VD/VT), to determine the currentsourceIso that the output voltage is 1.5 V. b) If a load is attached to the output that draws 1 mA, what is the output voltage? c) If the circuit heats up to 40◦C, what is the output voltage without a load?

0- Examine the circuits shown below for each half cycle. On each circuit indicate clearly which diode is on and show the path & direction of the currents. Use 2nd approximation for the diodes. a) What type of circuit is this? b) What is the total peak secondary voltage? c) Find the peak voltage across each half of the secondary (Circuit #1). d) Sketch the voltage waveform across R₁. Circuit #1 0 e) What is the peak current through each diode? f) What is the PIV (peak inverse voltage) for each diode? Circuit #2 120 Vrms 4:1 M: 120 V ms 00000 00000 D₁ LOKO R₁ 10 k Vp 120 V pe 120 V mms 100000 D₂ D₂ D₁ D₂ D₂ LORE R₁ 1.0 k

The following circuit uses two Zener diodes with reverse breakdown voltage of 5.1 V for each. (1-a) Explain the operation of the Zener diode in forward and in reverse bias. (1-b) Analyze the circuit thoroughly assuming many source values that lead to all possible cases of diode states. For each case (Hint: 3 cases), re-plot the circuit and develop the relation between the output voltage and the source. (1-c) Draw input and output waveforms accurately over 0.5-ms period. Identify the diode states on the graph based on the categorization of cases from part (1-b). (1-d) Use Multisim to verify all of your results. Compare andcomment.

Two identical Schottky diodes are connected in series, one in the forward and the other in reverse direction, see figure. Assume the reverse saturation current, IS, of each diode to be known. Derive he current-voltage curve I(V) of this circuit. Plot it with the ratio I / IS on the y-axis and V / Vth on the x-axis. Make sure to cover a broad range of voltages, say, from –10 Vth to 10 Vth.