3.1 Name the type of material used for the gate terminal in a P-channel JFET - NSC Electrical Technology Electronics - Question 3 - 2019 - Paper 1
Question 3
3.1 Name the type of material used for the gate terminal in a P-channel JFET.
3.2 Draw a neatly labelled symbol of an N-channel JFET.
3.3 Study the symbol in FIGUR... show full transcript
Worked Solution & Example Answer:3.1 Name the type of material used for the gate terminal in a P-channel JFET - NSC Electrical Technology Electronics - Question 3 - 2019 - Paper 1
Step 1
3.1 Name the type of material used for the gate terminal in a P-channel JFET.
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Answer
The type of material used for the gate terminal in a P-channel JFET is N-type semiconductor material.
Step 2
3.2 Draw a neatly labelled symbol of an N-channel JFET.
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Answer
The symbol for an N-channel JFET should be a transistor symbol with three terminals labeled as follows: Drain (D), Gate (G), and Source (S). The arrow on the Gate should point inward, indicating that the current flows into the gate.
Step 3
3.3.1 State whether the field-effect transistor (FET) in FIGURE 3.3 is a P-channel or an N-channel.
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Answer
The field-effect transistor (FET) in FIGURE 3.3 is a P-channel.
Step 4
3.3.2 List THREE conditions for the correct biasing of the transistor in FIGURE 3.3.
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The drain must be connected to the positive voltage.
The source must be connected to the negative voltage.
The gate voltage must be positive.
Step 5
3.4.1 Besides a sawtooth generator, name ONE other application of a UJT.
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One other application of a UJT is in oscillators.
Step 6
3.4.2 Explain what causes the UJT to trigger ON in the circuit.
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The UJT triggers when the voltage across the capacitor rises to 0.7 V above the intrinsic stand-off ratio (Vx or Vb).
Step 7
3.4.3 Draw the output waveform between points B1 and ground on the ANSWER SHEET for QUESTION 3.4.3.
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Answer
The output waveform will typically show a sharp rise when triggered and a subsequent drop, resembling a sawtooth shape.
Step 8
3.5.1 State how you would identify pin 1 of the IC in FIGURE 3.5.
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Pin 1 is identified by being the first pin to the left and below the indentation on the IC.
Step 9
3.5.2 List the THREE stages into which the internal circuit of the op-amp is divided.
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Input stage, which is typically a differential amplifier.
Intermediate stage, which is a high gain differential amplifier.
Output stage, which is often a common collector.
Step 10
3.6.1 Calculate the output voltage based on the data in FIGURE 3.6.
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Answer
To calculate the output voltage (VOUT), we use the formula:
VOUT=VIN×(RNRF)
Substituting the values:
VOUT=2×(12×103100×103)=−16.67V
Step 11
3.6.2 Explain why the shape of the output waveform is NOT an exact replica of the input waveform.
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The shape of the output waveform is not an exact replica of the input waveform because the amplifier is driven into saturation, clipping the tops and bottoms of the waveform, resulting in a 180-degree phase shift.
Step 12
3.6.3 Identify the maximum output voltages (VOUT).
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The maximum output voltages (VOUT) can be identified as +15 volts and -15 volts, based on the supply voltage levels.
Step 13
3.7.1 Rewrite the abbreviation DIP in full.
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DIP stands for Dual in-line package.
Step 14
3.7.2 Write down the maximum supply voltage for the NE555 IC.
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Answer
The maximum supply voltage for the NE555 IC is +15 volts.
Step 15
3.7.3 Identify the typical trigger voltage of the NE555 IC, in the data sheet above, when the supply voltage is +15 V.
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Answer
The typical trigger voltage of the NE555 IC, when the supply voltage is +15 V, is 2/3 of VCC, which is approximately 10 V.
Step 16
3.8 Explain what will happen to the output of an NE555 IC when the trigger voltage rises above the threshold voltage level of 10 V.
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When the trigger voltage rises above the threshold voltage level of 10 V, the output of the NE555 IC will switch to a low state, signaling a change in its output behavior.
