I prefer 74xxx14, reliable, works every time for me.
And I also have used S.T. NAND gates as reliable oscillators.

On Apr 20, 2013, at 12:53 PM, Peter P. wrote:

> Problems with 74HC(T)xxxx and CMOS4xxx IC 'linear' circuits.
>=20
> The following reproducible problems were found in several
> popular 'analog' applications of CMOS gate based circuits.
> The circuits are tried-and-true 'old' circuits from the
> 1980s and 1970s, as published in datasheets and application
> notes from various name silicon makers.
>=20
> 1 - inverter-with-feedback-resistor does not work or oscillates
> uncontrollably. Occurs with 74HC(T)xxx circuits, any. Using any
> feedback resistor over a simple inverter in a 74HC(T) circuit=20
> causes the gate to oscillate at over 10 MHz. The resistor value
> does not matter. The oscillation also occurs if an external
> precise bias source is used to bias the input, without using a
> feedback resistor. Source impedances tried ranged from 1 ohm to
> 10Megohms. Consequences:
>=20
> - It is not possible to build low frequecy Xtal oscillators=20
> using 74HC(T)xxxx gates. Example: 32767kHz osc on 74HC(T)4060
> will not work, it oscillates at several MHz. Manipulating the
> usual Pierce oscillator part values around the xtal does not
> help. This does not appear anywhere in the datasheet.
>=20
> 2 - CMOS oscillators built as above with gate-and-feedback
> resistor stop working when the supply voltage is taken up
> above 5V. Example: CD4060 with 32768kHz Xtal using datasheet
> Pierce oscillator values (2.2kohms, 2x33pF, 2M2 feedback),
> works fine at 5V but stops working at about 7V supply and is
> impossible to start at 12V. My assumption is, that there is
> some 'new' 'feature' caused by die shrinks which increases
> leakage at the input and/or lowers output impedance somehow,
> or that gain decreases with voltage somehow in the 'deadband'
> dc bias region.
>=20
> In all cases I tried several Xtals (3 makes), and several ICs
> (2 or 3 makes each). All ICs were new (datecode >2007). I did
> not try old old parts (CD4060 etc) beucause I know they work
> fine.
>=20
> Any comments would be welcome here. I am a little stumped by
> these new features. I tried the above several times (incredu-
> lously, after having used cmos parts since the early 1980s
> with no problems).
>=20
> What IS going on, in your opinion?
>=20
> Comments, etc., are very welcome. Tia,
>=20
> -- Peter
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