Ceramic Packaged Oscillators with "S" in the PN
Written by on 5/25/2010Many Pletronics older oscillator part numbers had the letter "S" in the part number. For example, SM7745HSV-25.0M. This "S" was used to indicate that this part was specified to meet a logic high level duty cycle of 45% to 55% range. The standard specification was for a 40% to 60% duty cycle range.
As technology improved, that is the integrated circuits used to make the oscillators all actually met a 45% to 55% range without any testing or screening. All ceramic packaged oscillators from Pletronics were in fact meeting this 45% to 55% duty cycle range.
Since the "S" had no official meaning, this was dropped from all part numbers for ceramic parts. Therefore an example: the SM7745HSV-25.0M is the same as the SM7745HV-25.0M and both parts have a 45% to 55% high level duty cycle.
Part numbers with the "S" in them are accepted but have no special meaning.