Olimex Support Forum

DUINO => SHIELDS => Topic started by: shikolay on May 12, 2014, 06:28:29 PM

Title: Which signal measured in EMG/Ekg shield.
Post by: shikolay on May 12, 2014, 06:28:29 PM
Hi Olimex. I check EKG/EMG schematic and confuse a bit.

Which signal it's measured (U - is voltage)
U_right - U_left
or
(U_right - U_left) - U_ref

Can you write me a approximate formula. For example if i measure that signal from shield is 2.2 Volts, what voltages i have on my electrodes?
Title: Re: Which signal measured in EMG/Ekg shield.
Post by: LubOlimex on May 18, 2014, 10:31:27 PM
Hey shikolay,

The formulas are in the red rectangles over each block. To reach the first step of the instrumental amplifier (where you need the values of R8 and R7) you need to do some basic calculations.

Best regards,
Lub/OLIMEX