Single Stage MOD2 Counters Virtual Comparison

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 :

The 1-st design i once came up on my own - after studying the function of 7474
1572206104616.png
1572206111830.png
the C1 stands for negative going pulse triggered , C0 for positive going 1​
the Yellow is non-inverting output K1 -- and the Orange M1​

the second is modified master slave D-Flop the CMOS counters and registers use
1572206118521.png
1572206126405.png
Red Clock means C0 , means positive going clock triggered change​

3-rd : JK-trigger to MOD2 or D-trigger -- it's about how you configure it
1572206133814.png
1572206140687.png
doubling the gate control before the OUTPUT_RS-Trigger reduces occasional instabilities​

The 4-th -- the 7474
1572206149375.png
1572206155133.png

Finally something i call a pulse counter (a modified Pulse RS-Trigger)
1572206161507.png
1572206167309.png
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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PS! _n_o_n_e_ (no any) 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 !!!
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Update 2018-12-31 23:12 UTC :: Apx. LTSpice definitions used for above logic gates ::


Value2 = >>
BUF Vhigh=5 Vlow=0 td=5n
SCHMITT Vhigh=5 Vlow=0 td=6n vt=2.1 vh=.44 (apx. 74HC14 . . . most likely . . .)
- - - - - - - - - - - - - - - - - - - - - - - - ! , 3/7 , (3/17)/2 -- of the Vhigh
NAND Vhigh=5 Vlow=0 td=7n
NOR Vhigh=5 Vlow=0 td=11n
SR3G Vhigh=5 Vlow=0 td=13n
XzOR Vhigh=5 Vlow=0 td=23n
DFLP Vhigh=5 Vlow=0 td=41n
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