Hello,
im a big Teensy fan, here my first question.
This schematic of the Teensy 3.6 implies that i should measure no resistance between the AREF pin and VREFH. VREFH i think i can get at one of those two 100nF capacitors, point 2 in my uploaded picture.
Also i should read 470Ohm between point 1 and 2. Point 1 is the output of the LP38691.
Actually i measure 470Ohm (component A) between VREFH (point 2) and the AREF pin, and 0Ohm between point 2 and 1. So either im wrong in measuring VREFH at point 2, or the schematic is wrong in this point (i asume it to be the first case).
My goal is to usa a REF1930 as external reference for the internal Teensy ADC, and i thougt i have to remove the 470Ohm resitor to disconect VREFH from the supply voltage.
Second question, could i lower the ADC noise by increasing the capacitance infront VREFH by a factor of for example 10? Is the DAC getting his voltage reference directly from the internal reference with no way to improve its noise performace?
Greetings,
storm
im a big Teensy fan, here my first question.
This schematic of the Teensy 3.6 implies that i should measure no resistance between the AREF pin and VREFH. VREFH i think i can get at one of those two 100nF capacitors, point 2 in my uploaded picture.
Also i should read 470Ohm between point 1 and 2. Point 1 is the output of the LP38691.
Actually i measure 470Ohm (component A) between VREFH (point 2) and the AREF pin, and 0Ohm between point 2 and 1. So either im wrong in measuring VREFH at point 2, or the schematic is wrong in this point (i asume it to be the first case).
My goal is to usa a REF1930 as external reference for the internal Teensy ADC, and i thougt i have to remove the 470Ohm resitor to disconect VREFH from the supply voltage.
Second question, could i lower the ADC noise by increasing the capacitance infront VREFH by a factor of for example 10? Is the DAC getting his voltage reference directly from the internal reference with no way to improve its noise performace?
Greetings,
storm