Help modeling a 4060

I think you could make a macro using a 4020, a nand gate and a handful of inverters. Just make sure you get the total number if inversions right. It doesn't matter if the clock gets nand'ed with /reset twice.

Hi Terry,

As the previous poster says, a 4020 plus a few external gates should do it. I reckon what you need is basically as the bottom diagram of your pdf. Add the nand and the first 5 inverters: output of the third inverter after the nand is the clock input of the 4020, so with the nand you have an even no. of inversions, and hence the same clocking sense for your '4060' and the

4020; output of the second inverter in the reset chain is the reset input of the 4020 (and again an even no. of inversions, so the same sense). Pins 9, 10, 11 (of the 4060) are then as the bottom diagram, and other relabelling of the output pins as necessary.

SIMetrix does have a model of the 4060, and surprisingly it is written using toggle flip-flops, rather than their proprietary 'arbitrary logic block': however this seems to be using the XSpice primitives, so how useful it would be I couldn't say...

Tim

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Tim Stinchcombe

Cheltenham, Glos, UK

Thanks both. Guess I'll have another crack at it then, as you're both confident it can be done. But the penny has not yet dropped here! Surely, if I add external NAND and a number of inverters, won't that screw up the existing 4020 circuitry?

Tim: CircuitMaker 2000 uses Berkeley Spice3f5/XSpice, so maybe that SIMetrix model could be useful. I have SIMetrix 3.0, but used it only superficially in 1999. With a 4060 placed in a new schematic, what steps do I take to see its model please?

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Terry Pinnell
Hobbyist, West Sussex, UK

Terry,

Ah ha, I see you want it as its own symbol (or 'macro' as you say). This should be do-able: you'll probably need the new 'device' to be a 'subckt', which contains the new gates plus the 'call' to the 4020 model. Then you'll need to work out how in CircuitMaker you create a new symbol for your 4060, which will then need associating with the subckt (which is just a self-contained netlist), along with the pin allocations. I'm making lots of assumptions here about CircuitMaker: If I were you I'd make and test the

4060 circuit as normal, using the extra gates and the 4020, then look at the netlist to see what it has done (no idea how easy or otherwise this will be - it's a piece of cake in SIMetrix, but a nightmare in Multisim!!!) - this then forms the basis of your model. Then you are left with finding out how to make a new 'library item' from a new symbol and netlist....possibly too much work and not worth it, to relatively easy, depending on your state of mind and how easy CircuitMaker is to use!

I don't think there is a quick way to the model from the schematic - I always go directly to the appropriate model file. This is displayed at the bottom of the 'Place, From Model Library...' pop-up, and will be something like "c:program filesSIMetrix??modelsdigitalmsi.lb". It's just a text file with the Spice subckt/model netlists for the components. (And bear in mind that SIMetrix is not _strictly_ XSpice: it has been extended and chopped about.)

Tim

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Tim Stinchcombe

Cheltenham, Glos, UK