Sunday, February 19, 2017

ADC test

incomplete Σ Δ ADC -- since i don't quite grasp it's operation yet -- just to see where it goes . . .


the CLK not verified as opt. for this v. but for it's predecessor that was tracking the analog input with the analog summer - the D-Flop output was basically the same only it was without the U/D counter ...

the following shows the effect of resetting the U/D count to 0 after specific time interval (number of clocks)
--  the effect with pure*sine wave here is the "reset" (actually a periodic substraction of some constant) integrates the derivative of it* back to it* -- it's a lot of tedious testing to determine what to actually implement in circuit . . . but the following is showing the prev. test being on the right track





what is surprising here is that the lesser number of clocks gives better results ???

[Eop]

DAC test

CD4069 outputs are referenced to supply median


checking if such produces a linear ramp . . .
all fun of resolving a simple 3 - supply voltage divider (finding the formula for UX)


. . . checking if such produces a linear ramp in excel . . .
-- the value 1/2 used in LT Spice seems to be incorrect . . .



[Eop]

Sunday, February 12, 2017

Absolute Voltage 2

the followup of the prev. post -- tested the experimental reference + came up with a new 1


the near zero error gives us the "absolute" voltage ref. -- tough -- there's no information about it's response to varying temperature !!!



[Eof]

Thursday, February 9, 2017

some experimental 1.2V supply designs + rnd. osc. variant

Originally designed for 3-5V operation , also studied for 1.2V
as with the 555 --  the basic operating mode's to generate low duty pulses -- economizing the battery



 Hi precision supply -- preserving near ® precision and with added current limit


Simple not limited 1.2V linear voltage regulator


the Op Amp variant of the above " Hi precision supply" without current limiting
-- the design has a "new" type of adjustable voltage reference that has not especially been optimized nor tested for varying operating conditions !!! (i just needed one and simple here !fast (as in common))



+ some more : update 2017-02-13 (1-st time to break the ±1µV error !?)



[Eop]

Sunday, February 5, 2017