Refer to FIGURE 2.2 below and answer the questions that follow - NSC Electrical Technology Digital - Question 2 - 2019 - Paper 1
Question 2
Refer to FIGURE 2.2 below and answer the questions that follow.
### 2.2.1 State the function of R1 and R2.
### 2.2.2 Describe what happens when the set switch, S1,... show full transcript
Worked Solution & Example Answer:Refer to FIGURE 2.2 below and answer the questions that follow - NSC Electrical Technology Digital - Question 2 - 2019 - Paper 1
Step 1
State the function of R1 and R2.
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Answer
Resistors R1 and R2 are pull-up resistors that determine the threshold and trigger levels in the bistable multivibrator circuit. They help in stabilizing the state of the circuit and control the timing intervals for toggling between states.
Step 2
Describe what happens when the set switch, S1, is pressed.
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Answer
When the set switch, S1, is pressed, it pulls the Reset pin low, causing the output of the 555 timer IC to switch from low to high. This transitions the state of the LED, turning it on, as the output voltage goes high, allowing current to flow through the LED.
Step 3
Explain why threshold pin 6 is connected directly to ground.
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Answer
Threshold pin 6 is connected to ground to ensure that the voltage at this pin remains at 0V. This constant voltage level keeps the monostable multivibrator stable and allows the circuit to reset properly when toggled, ensuring reliable operation.