In datahseet of 74HC4046, page. 10.
Why the typical value may bigger than the max. value, or lower than the min. value? I don't think it's a typo, because there are others like this, such as p. 16
Any reason? What "typical" mean?
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HC4046 is featured on www.bedbeetles.com The 4046 does have some snags. – Autistic Jan 07 '16 at 04:12
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I can't open the size you posted. "snags"? Then, can you explain more? Or if can recommend another better chip. – diverger Jan 07 '16 at 04:17
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There is only the tip of the iceberg on the website .I didnt design the website .I will check that it still works . – Autistic Jan 07 '16 at 04:20
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I think you mean "http://www.badbeetles.com", "bad" not "bed" :). – diverger Jan 07 '16 at 04:21
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Those are not typos. You are not interpreting the specifications correctly. For the HIGH levels, the specification is giving the minimum value that is guaranteed to be recognized as a HIGH, e.g. 2.1 volts when Vcc = 3.0 volts. Any voltage higher than 2.1 will be recognized as a HIGH. The typical voltage, 1.7 volts, is the value that a typical device will recognize as a HIGH but it is not guaranteed. Similarly, the maximum voltage that is guaranteed to be recognized as a LOW is 0.9 volts when Vcc = 3.0 volts. Any voltage lower than 0.9 volts will be recognized as a LOW. Typically, however, a value as high as 1.2 volts will be recognized as a LOW, but again this is not guaranteed. All of the other values in the specification should be interpreted in the same way. In general, maximum and minimum values are guaranteed, typical values are not.
Barry
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I thought there are some relation to the word "typical". I usually thought it's the value "recommended". But here "typical" means for other HC chips, the 1.7V usually be recognized as HIGH safely, but HC4046 not, it shows here to avoid wrong using, right? – diverger Jan 07 '16 at 04:04
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Right. If your Vcc is 3v and a LOW level is 1.1v, it will probably be interpreted as a LOW on that pin, but it is not guaranteed. *Min* = minimum guaranteed HIGH level, *Typical* = usually works here, *Max* = maximum guaranteed LOW level. – rdtsc Jan 07 '16 at 04:19
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The first parameter is giving the lowest voltage that the chip will treat as a HIGH on its input. It is saying it will always recognise 2.0V as a high but will typically recognise down to 1.7V.
David G
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"typically recognize down to 1.7V" doesn't mean "always recognize down to 1.7V" right? – diverger Jan 07 '16 at 04:14
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It means most chips will 'typically' recognise 1.7V as a high but all chips WILL recognise 2.1V as a high ie the minimum. – David G Jan 07 '16 at 05:09