Pre notice: the following has some numeric values listed that are to be taken with certain respect as the LT Spice (used to derive those numbers) uses an equitable , say a "P/N-MosFet-s" , to form it's quantized OUTPUT , the performance of these counter types is much dependent on actual hardware/technology used -- so basically the chapter is much about nothing , i only needed a reliable D-flop for a bit more sophisticated virtual "Digital" implementation of such
The variety :
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PS! none of these Flops were tested this time at slow changing inputs - it's because they are idealized and won't perform much differently - but the realistic ones may start to strobe and function unpredictably at such !!!
The variety :
The 1-st design i once came up on my own - after studying the function of 7474
![ct100.gif]()
![td100.gif]()
the C1 stands for negative going pulse triggered , C0 for positive going 1
the Yellow is non-inverting output K1 -- and the Orange M1the second is modified master slave D-Flop the CMOS counters and registers use
![ct110.gif]()
![td110.gif]()
Red Clock means C0 , means positive going clock triggered change3-rd : JK-trigger to MOD2 or D-trigger -- it's about how you configure it
![ct120.gif]()
![td120.gif]()
doubling the gate control before the OUTPUT_RS-Trigger reduces occasional instabilitiesThe 4-th -- the 7474
![ct130.gif]()
![td130.gif]()
Finally something i call a pulse counter (a modified Pulse RS-Trigger)
![ct140.gif]()
![td140.gif]()
amazingly -- turns out to be the winner of this little contest . . .
. . . with more realistic Digital Logic Gates the best performing competitors tend to be JK-Flop and 7474
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the C1 stands for negative going pulse triggered , C0 for positive going 1
the Yellow is non-inverting output K1 -- and the Orange M1
Red Clock means C0 , means positive going clock triggered change
doubling the gate control before the OUTPUT_RS-Trigger reduces occasional instabilities
amazingly -- turns out to be the winner of this little contest . . .
. . . with more realistic Digital Logic Gates the best performing competitors tend to be JK-Flop and 7474
¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯
PS! none of these Flops were tested this time at slow changing inputs - it's because they are idealized and won't perform much differently - but the realistic ones may start to strobe and function unpredictably at such !!!