Low Voltage SCS Counter Experiment

. . . integrated the www resource (poor) with my past experimental Lo voltage SCS designs . . . to just about get a working theoretical "New One" -- the 2 things marked on a fig. tell us that such is not likely to succeed in practice ...

actually i was playing around with oscillator designs the SCS-s in mind -- the cool feature about this thing (scs) is like some modern GHz MOSFET counters also DRAM e.c. those things can be designed to use practically no current and then shift 'em to another state by a narrow pulse

so, while i achieved my next osc. i studied in parallel an old electronics book - came across with ?? neg. triggered ring counter ?? thought to investigate it , improved the "CLK" shown in book for 1.2V supply . . .

after no success with the counter i actually realized that the TYPE of a counter i'm using for my improved CLK uses the pos. going pulse . . . yo!

. . . usually i finish what i started so the 1.fig. of this post actually shows the finished 1.2V design

for incase i'd ever need such in practice - i converted it to higher vtg. v. where the SCS is more likely to operate in realistic supply range . . . -- the ▼ "signal forward continuity test" ▼

► what's it made of ▼▼

it's tricky to get the signal out from low power "oscillators" -- here's one possibility :

PS! -- as the simulation in Spice may perform up to 1000x better than the actual circuit in real then it's not recommended to rush blindly building large systems composing them from the unknown / not studied designs
-- it's about 1 to 1k x that averages to ²√(1·1000) = 30dB = apx. 32x in general (more usually it's about 10x - maybe coz i ban the designs that perform worse ...) -- to get this right -- say if your 10Vdc PSU design has a simulation peak error ±24µV then in real device the appropriate value is to be expected ±24mV -- so it's 1000x change in relative error . . . as ±24mV/10V is ±0.24% then the common understanding of 1k x performance drop can't be grasped right without knowing the preceesding

 -- it's also why i don't build much of the stuff -- coz it takes testing separate stages . . . 1 by 1 . . . also verifying similar (same circuit) stages built from real components (with deviating parameters) that usually ends up in narrowing the operating ranges . . . without all possible fancy lab equipment in hand it takes more time than there is available . . .

... e.g. if you find such (SCS counter) interesting you have to perform further development-testing with (/based on) the real components you have in hand for such . . . before attempting to integrate it to any larger application !!!

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Custom pF Capacitors

Since i usually don't use below 30pF capacitors - and i'm lazy enough not to order such for just incase -- i tried to build some from the bits of used carpet cutter blades ...

Fig.1

Shows the 4-,2-, and 1 segment capacitors
The surfaces were cleaned with P500 then P1200 , the wires and plates were pre-soldered prior attachment using the Kristall 511

... targeting the 4 to 20 pF range. I actually mishit a lot testing the 16µm paper for dielectric . . .
 So i varied the sizes and dielectrics and attempted to collate some science out of that

The physical dimensions :

Fig.2

showing the capacitor plate omitting the sharpened edge geometry

And the atats. -- had to recalibrate the Kyoritsu's KEW1018 measurements against the set of commercial capacitors from 15 to 180 pF -- here's what we got :

Fig.3

Shows the Cap.-meter re-calibration logic

Fig.4

Shows the Old and the New calibration curves -- the Red one shows the difference and actually is an optimistic error estimate for the measurement at X-axes plot capacity

 Next -- matching the TEST and the THEORY (using the Old calibration formula - it takes an error trial to match the measurement to unknown actual capacity . . . ) :

 Fig.5

-- as it might've been guessed -- the larger blades´ surface geometry (used carpet blades) falls far from the ideal - thus the inserted 16 micron dielectric has a lot of free space from it to the razor blade -- the lllliiiillll illustrative graphs show the dielectric-gap for ideal smooth surface and what the actual average of what it came out

Fig.6

(it actually "rolls toward you" close your eyes momentarily - keeping that in mind - if your brain suggest a different solution !) -- shows in relative scale the last assembled 6pF capacitors with double-layer 2× 240 micron dielectric -- these capacitors had the least capacity deviation inside the set -- which is obvious because the µm variations won't have much effect for average plate distance

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Verifying the MOSFETs´ RDS(ON)

. . . being used to BJT-s i always thought the R_DSON being some illustrative variable that has nothing to do with reality - amazingly enough the tests i performed verified it being NOT a theoretical figure !

used the MOSFETs (IRFZ44N and BUK455-60A) unmounted from cordless drills´ speed adjustment circuits

the IRFZ44N existed in Spice DB but for the BUK455-60A i used a model compilation method described in the [LT Spice Tutorial 6] website (which actually resulted in better match with reality this time ??)

 as for R_DS(ON)

as and for directly measured I_D, U_D, U_G

ah! - also modified in ↑that↑ spice tutorial the files RDSon test jig and Switching Time Test Jig coz they were totally impractical to use for given purpose (fine tuning your MOS-Fet models) respectively to Cust MosFETs - 01.asc and Cust MosFETs - 02.asc (note that you have partially pre-calculate and modify accordingly the component parameter values to get your response right)

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Update!

PS! Since the power supply (Mod.: SMP-100KB, Rev.: A3, Date Code: 8945, +12Vdc/3.75A - output) was not very stable (or depended on it´s ~AC input ???) the source data can be trusted from 1 to 3 digits (depending on conduction state of the FET and stability of the PSU) and contains extra to that the unknown systematic +other errors of the multi-meters -- this was not intended to be a precision measurement anyway - but for setting the apx. (static) device margins (near +25°C).

also there were used voluntary statistical alterations to guess better the values required to form a "believable" (?accepatable) output for R_DS .


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rev. +1.2V Linear Voltage Regulator with Current Limit

not built in real yet /!\ e.g. possibly no reverse pol. prot. + unknown amount of spec. not handled states ...

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CD4043 К561ИР6

**as usual the datasheets contain typos - so it's hard to guess if there's any bugs left
russian v. http://vicgain.sdot.ru/spmikro/smikr15.htm

some basic test (P/S , A→B , B→A) ::

acync. transfer from A to B (with switching A to high impedance state) ::

v.B is by** Ti datasheet , v.no-ext is by** National'-s ds. v.py is by К561ИР6 spec.-s  ► src.2016-06-17

clearifying the function of C_M,C_S AND C_М,C_П (TOP RIGHT) ::

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