Not having an adequate CD4060 spice model I tried emulating a 4060 by following the CD4060 datasheet schematic and bolting on a couple of gates to a 4020 model in the CD4000.lib library downloaded from the Yahoo LTspice user group. The added gates are configured as a clock oscillator as per the datasheet. The Q4 output of the 4020 should be pulsing at 1/16 the clock rate but, for some strange reason, is variably at 1/5 or 1/6 the clock rate. Any thoughts on why? On its own, when clocked by a normal PULSE voltage source, the 4020 model seems to behave itself.
![4060-emulation.gif 4060-emulation.gif](https://www.electro-tech-online.com/data/attachments/80/80856-cb58161754c77d4d82dcc486fd413881.jpg)
![4060-emulation.gif 4060-emulation.gif](https://www.electro-tech-online.com/data/attachments/80/80856-cb58161754c77d4d82dcc486fd413881.jpg)