Tuesday, June 30, 2015

SN74xXX transistor level models

Tested the SN74xXX transistor level models + some features

( extends about :: http://chpsndtch.blogspot.com/2014/08/spice-alternate-for-sn7404-1551.html )





+ A RANDOM OSCILLATOR SETUP ::

what a waste of power for 50MHz ( actually it's for high "slew rate" for level transitions & "output replicate-ability" . . . anyway insane . . .)




[EoP]

Sunday, June 28, 2015

about -- LM308 models

intuitive/error-trial setup ::



modified from bias.pdf ::

the 2-ble J-fet v. ( chk the pre prev. post )

[EoP]

Friday, June 19, 2015

BWD engineering the GPSA006W3

very apx.* op. of the Solar Charger

PS! the numeric values on the plot are illustrative*

the valid formula for thishit seems to be ::
IF no clouds
prod. ( ( 8h/d + 4/2 h/d = ) 10h/d ) × 43.6mA = 436mAh/d
apx. 5d to charge batteries from 20% to 100% of nom. capacity
( usually it takes 2 to 3d . . . ? 55% to 95%  e.g 4x SB in parallel (60 in²) should 2 the 3-ck in 1d )


Update : results of a "Quick Test" (applies to solar cell only) ::

EP -- ( values below (have likely 1.5 to 2.5 significant digits !!!) ) based on solar-cell´s double output power !!! or max. power diffused on internal resistance at short circuit !!! -- sampled on 2 spring afternoons @ apx.60°N (Sun filtered by Space´s dust + Earth´s atm..+ packet-window´s 2-ble layer of Si-glass)

Est.Peak double output power ( P2PK (= ε · r) ) : 1.163698202 W
*Speculative "no load" terminal voltage ( ε ) : 6 V
*Computed internal resistance ( r ) : 30.935856 Ω

note : * --  the values are valid for P2PK or at max. "intensity of a Sun" and will respectively drop,increase at lower intensity levels + there are reason to believe that ε , r also depend on load ( I²R )

Update+ : refined experiment (sampling the I , U and ε) ::


[Eop]

Thursday, June 18, 2015

about -- NiMH charging & LM308 models

NiMH Charging :: notes
charging from 12.6 V automotive 70Ah PbSO4
(a) initial current no load limit 100mA and grows fast
-- faster when cell is more empty - up2 10+ A !!!
(b) initial voltage current limit 50Ω 4W metal film
2.17V [12:23] after 2+ h charging
1.72V [15:34] 3h 600mAh 1:4-th of capacity
1.85V 190mA [17:25]
1.79V 190mA [17:50]
1.79V 190mA [18:13]
1.79 1.800 V 190 mA [19:33] 7.2h 1400mAh(200mA) 60%
1.80 1.798 V 190 mA [20:20]
1.79 1.796 V 190 mA [21:12] 8.8h 1675mAh(190mA) 70%
-- ??? so far the battery have had no heating up over the ambient
-- (whitch would indicate reaching the full charge) ??? (see *note)
1.77 1.782 V 180 mA [22:39]
1.77 1.777 V 190 mA [23:17] 10.9h 2071mAh(190mA) 78% (*2650mAh)
1.78 1.788 V 190 mA [ 0:21] 11.6h 2274mAh(190mA) 86% Label.val*
Final 1.489 >> 1.463 >> 1.340*

1.770 V 190 mA [ 0:27] start.2 *%
1.610 V 190 mA [ 2:09] 1.7h 323mAh 12%
1.600 V 190 mA [ 9:11] 8.7h 1659mAh 63%
1.600 V 190 mA [10:51] 10.4h 1976mAh 75%
1.596 V 190 mA [12:38] 12.2h 2315mAh 87%
Final 1.486* >> 1.450 >>

* note :: the DURACELL´s MODEL : CEF14KTNEU
-- INP : 100÷240~VAC 50/60Hz 8W
-- OUT : 5.6V 360mA (4x AA NiMH) / 2.8V 160mA (2x AAA NiMH)
as i remember output some 300÷320mA and heated up the AA-s
while the Resistor Ltd. charging of 190÷240mA did NOT !!!
??? are the factory chargers in purpose set to shorten your
accus lifetime ???

LM308 LT-provided & customized component level model compared ::
[BLUE : GREEN : RED] CustomCL.1 : CustomCL.2 : LT´s - .CIR
The TEST is setup to minimize the batch err. -- however never verified that this is what it actually does !!!
... minor modifications ...


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Fast / poor instrumentation mode test ::
["BLUE"]
["GREEN"]
["RED"]

[EoP]