i got this questions on a quiz:
given list of problems think of the possible causes:
1)seven 7segment of LED shows nonsence
2)pilot light turns off when you connect the circuit
3)chip toooo hot(burned)
4)one of the pins on a chip is neither high nor low
5)all the pins on a chip are high
6)chip only works when u press down with ur finger(into the board)
7)all ther LED outputs of a counter are on and seem to flicker(light brighter then less brighter)
8)all the pins of a chip are low
9)all the pins of a chip are high
10)a shift counter reaches a certain state then gets stuck there
counter stays in the state that is turned on . does not change at all
11)binary counter gives the sequence:0,8,3,10(wrong sequence)
essay problem answers
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1)what will IC tester display if you plug the chip upsidedown and press "Search"
2)what will IC tester display if you plug the chip upsidedown and press "Go"
3)why are resistors used in ROM smaller then that of RAM
4)name 3 chips could not be tested by IC tester
5when does IC tester give :Error,Fail,unidentified
6)in which cases u expect Vcc pin to be broken and in which Ground Pin broken
7)how can u use trainer bord to provide DC voltage
8)why do binary switches have 2 complementary outputs
9)what is the role of capacitor(ceramic) in the 555timer
10)why did the IC tester sometimes fail to recognize a healthy chip when given its number,but did give an answer when search button was pressed
11)why arent LM339 and 741 opamp interchangable
