i've a prob check integrated circuit (ic) etc 74HC00 or 74XXXX?

Question

prob is:
1. from my knowledge, ic logic input/output give HIGH when reading value of multimeter >3.2volt, normally 5volt..whereas LOW when reading value of multimeter <1.8volt, normally 0 volt.. am i correct?
2. What happent when the ic logic input/outpu give reading between 2-3volt.. is it the ic been damaged and need to replace?

Answer 1

Check the voltage of the power supplied to the chip (pin 14 if 14 pin dip package) and also check the voltage of the input levels. Remember, garbage in, garbage out.
If it all checks out good, then you have a bad chip.

Answer 2

YEah, your numbers for a 0 and a 1 sound about right. And getting something between 2 and 3 volts doesn't sound good. Have you checked the power supply? Maybe it's not putting out quite 5 volts.

HTH

Doug

Answer 3

Dilbert has a competent start up on your answer. The gate is noted as a CMOS for solid reason. The enter terminals of the gate are insulated from the the remainder of the gadget by ability of an extremely skinny layer of glass. tips is coupled by way of this junction capacitively. it extremely is the common clarification for the fee, and occasional modern requirement of such units. you somewhat could earnings from understanding what the actual layout of such units is with a view to be attentive to how they function. set up a attempt circuit for the gadget, and get an oscilloscope to computer screen the operation of the circuit, or gadget. using a modern meter could be ultimate accomplished with a digital multimeter. basically undergo in recommendations that the present stages are going to be very low, so the main gentle scale on the meter desires for use. With those issues in recommendations, except destruction of the gadget is a few thing it extremely is being appeared for, modern length could desire to get replaced by ability of pulse prepare remark and the final device for that's the two a digital analyzer, or an oscilloscope.