Exam paper question:
What happens to the voltage of the drivers input when the switch is pressed and released. With the help of the information in Fig. 8.1 draw and explain how the drivers output voltage changes with time.
Exam paper answer given:
At time t = 0 VIN = 0 and therefore VOUT = 4.5 V.
t = 3s, VIN goes to +5 V and VOUT drops to +1.0 V.
when switch is released capacitor discharges and VIN falls. VOUT remains at +1.0 V until VIN drops below 1.5 V at which point VOUT returns to 4.5V. This occurs at 15 s.
My answer:
When switch is pressed the capacitor is then discharged through the switch, then when its released the capacitor re-recharges - not discharging?
Where have I gone wrong?
Thanks
What happens to the voltage of the drivers input when the switch is pressed and released. With the help of the information in Fig. 8.1 draw and explain how the drivers output voltage changes with time.
Exam paper answer given:
At time t = 0 VIN = 0 and therefore VOUT = 4.5 V.
t = 3s, VIN goes to +5 V and VOUT drops to +1.0 V.
when switch is released capacitor discharges and VIN falls. VOUT remains at +1.0 V until VIN drops below 1.5 V at which point VOUT returns to 4.5V. This occurs at 15 s.
My answer:
When switch is pressed the capacitor is then discharged through the switch, then when its released the capacitor re-recharges - not discharging?
Where have I gone wrong?
Thanks
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