Thursday, December 28, 2017

www voltage multiplier test

src :: http://electricalnote.com/symmetrical-dc-to-dc-converter-with-ic555/
(i donno why they have to post circuits in the web that add up to the climate warming ...)


mod/fix ::
(the circuit'd do better with true complement wave drive -- e.g. -- a RS digital flop driving two powerful buffers -- in our case -- 555-s)



[Eop]

Tuesday, December 26, 2017

the Actual/Built LED verifier

as i was not about to build a PCB for this the sot-jFets were not used . . .

Spice design ::

Real build ::


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Friday, December 22, 2017

Comparing Constant Current Circuits (to sort/verify the LED-s with)

▼Fast/Simple/Robust/Trivial Op-Amp + BJT Setup▼
→ apx. 16mA ±30µA(0.2%)
[fig.1]
▼Complex/Trivial Op-Amp + BJT Setup▼
 → apx. 18mA ±24µA(0.1%)
[fig.2]
▼Simple/Experimental BJT Setup ( !? the Best ?! )▼
→ apx. 18mA ±60nA(0.0003%) 
[fig.3]
▼Full/Trivial BJT + N-jFet Setup ( also better than any op-amp variant ??? )▼
→ apx. 18mA ±300nA(0.002%) 
[fig.4]
▼Complex/Experimental Op-Amp + MOS-Fet Setup▼
(likely worse than it's BJT alternate -- the 2-nd ↑↑ fig. )
→ apx. 18mA ±120µA(0.7%) 
[fig.5]
▼Trying to get it right here▼
-- it seems that the op-amps should be fed from the separate supplies or otherwise the PSRR won't recover the precision reached at reference voltages
→ apx. 18mA ±48µA(0.3%) 
[fig.6]

((the work is in progress ...))

If you are stupid then knowing the right Op-Amp-s could save your day
(the node "SE" had the greatest error although the node "a0" has the least ??? -- about LT1012A)
→ apx. 18mA ±10µA(0.06%)
[fig.7]

-------- Update 2017.12.24 ::

▼a conditional opposite to "If you are stupid then knowing the right Op-Amp-s could save your day"▼

→ apx. 18mA ±7µA(0.04%)
 [fig.8.1]
a "Russian LM308" **
 [fig.8.2]
** it's nearest LT's substitute (so far)

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Wednesday, December 20, 2017

Saturday, December 16, 2017

Random Op-Amp TEST - 2

Heuristic Test /// note that no matter these results may seem poor , they are poor in conjunction to the (perhaps a poor) test setup and relative to each other - - - i never test poor amplifiers (e.g. something that i know will fail my application) or do not test such without especially denoting it . . . as in fact the TLV314 was the best performer of a previous tests of it's kind (Low-power , Low-Voltage CMOS Op Amps) - - - here we have a high slew rate and/or high slew rate to bandwidth ratio Op Amps tested (where the TLV314 is just for comparison)


Fuzzily about how it works



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