src :: http://www.brown.edu/Departments/Engineering/Courses/En123/Lectures/DAconv.htm
modified
?? -- sounds "fun"
best guess :: The Pipelined ADC-s
src::not found at web
apx. guess of the ADC circuit layout and biasing resistors
related ::http://chpsndtch.blogspot.com.ee/2017/08/4-bit-adc-improvement.html
base/radix 3 ver. :: uses the same amount of ic-s per cascade -- but has "exponentially" higher resolution
↑ the radix 3 output can be converted to binary by summers -- for example ↑
something similar found at www :: https://www.researchgate.net/publication/220365717_A_Low-Power_Capacitive_Charge_Pump_Based_Pipelined_ADC
at the sown ADC-s when switched to 5V single supply and the CMOS comparators and op amp-s -- the least can be extended with 74HC125 or ↓ 74HC126 ↓ (to gain the OC OE functionality of LM311) . . . in other words by these changes the circuit can be made faster
-
↑ there's some optimistic 2.5µs read window ↑ to stay at the precision of the shown 0 to 26 e.g. 27 level of quantization . . .
As a target of these tests -- i attempted to find suitable ADC - DAC combination to set up a successive approximation ADC
modified
?? -- sounds "fun"
best guess :: The Pipelined ADC-s
src::not found at web
apx. guess of the ADC circuit layout and biasing resistors
related ::http://chpsndtch.blogspot.com.ee/2017/08/4-bit-adc-improvement.html
base/radix 3 ver. :: uses the same amount of ic-s per cascade -- but has "exponentially" higher resolution
↑ the radix 3 output can be converted to binary by summers -- for example ↑
something similar found at www :: https://www.researchgate.net/publication/220365717_A_Low-Power_Capacitive_Charge_Pump_Based_Pipelined_ADC
at the sown ADC-s when switched to 5V single supply and the CMOS comparators and op amp-s -- the least can be extended with 74HC125 or ↓ 74HC126 ↓ (to gain the OC OE functionality of LM311) . . . in other words by these changes the circuit can be made faster
-
-
-
CMOS Radix-3 :: 2.5x faster than a "slow" LM324↑ there's some optimistic 2.5µs read window ↑ to stay at the precision of the shown 0 to 26 e.g. 27 level of quantization . . .
As a target of these tests -- i attempted to find suitable ADC - DAC combination to set up a successive approximation ADC
- as by adding cascades to shown cascaded(/pipelined) ADC-s -- the transition delay to LSB-s increases -- they don't much improve the final conversion speed
- basically the cascaded converters are a "Static SAR DAC" variants -- the SA delay still remains
- i must rethink the concept here
- -- either should use a parallel converter
- or try to incorporate/integrate a differential approach
[Eop]
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