Monady
Advanced Member level 4
reference voltage how to make
Hi dear all friends;
i have used of resistor ladder in order to making reference voltages(similar to ladder in flash ADC). but i have some problem with this ladder. reference nodes are connected to large parasitic capacitors via some switches. Thus when any of SWs, being ON, output of that SW, is not expected value. for example, instead of 350mV, it is 330mV.
i know that if i choose value of each transistor so small(e.g. 1Ω), mentioned problem will be solved, but unfortunately implementing such values are not realizable. i don't know that any substitution method is exist for making this reference voltage.
i would be appreciated for any suggestion.
(Now, my resistor ladder is made of 256 resistors and each resistor is 8Ω, technology is 0.18u)
Thx in advance
Hi dear all friends;
i have used of resistor ladder in order to making reference voltages(similar to ladder in flash ADC). but i have some problem with this ladder. reference nodes are connected to large parasitic capacitors via some switches. Thus when any of SWs, being ON, output of that SW, is not expected value. for example, instead of 350mV, it is 330mV.
i know that if i choose value of each transistor so small(e.g. 1Ω), mentioned problem will be solved, but unfortunately implementing such values are not realizable. i don't know that any substitution method is exist for making this reference voltage.
i would be appreciated for any suggestion.
(Now, my resistor ladder is made of 256 resistors and each resistor is 8Ω, technology is 0.18u)
Thx in advance