sensor jack:

Analogue side:

we used special balanced DC coupling op amp, total Gain = 50,000 to 50,458.

Amplifier differential impedance is 10 T ohm,

Input Bias current is ±1.2 PA .. ±2 PA.

10 M ohm to 100 M ohm resistance input coupling.

variable high cut frequency filter amplifier  Max 900 Hz -3bd.

Low cut 0.16 Hz at -3bd.

Common mode noise is up to 110 dB at 0..40 Hz.

Input Noise:

voltage noise

fB = 10 Hz to 10 KHz -> 0.6 µ Vrms .. 0.7 µVrms

fB = 0.1 Hz to 10 Hz -> 1.2 µ Vp-p .. 1.6 µVp-p

Current noise:

fB = 0.1 Hz to 10 Hz -> 12 fAp-p .. 15 fAp-p.

fo = 0.1 Hz to 20 KHz -> 0.6 fA/*Hz .. 0.8 fA/*Hz

Input Noise that depend on source impedance at 10 Hz:

10M ohm: 400 nV/*Hz, fB = 0.1 Hz .. 10 Hz -> 7.5µ Vp-p

1 M ohm: 120 nV/*Hz, fB = 0.1 Hz .. 10 Hz -> 2.4 µ Vp-p

100 K ohm: 50n nV/*Hz, fB = 0.1 Hz .. 10 Hz -> 1.2µ Vp-p

Analog side:

total Gain = 50,000 to 50,458. --> 25,000 (24,240 to 26,664)

Input Bias current is ±1.2 PA .. ±2 PA.   --> 4 PA (TYP)

variable high cut frequency filter amplifier  Max 900 Hz -3bd.  ==> 10% - 100% to sampling frequency -3db

Common mode noise is up to 110 dB at 0..40 Hz.  --> Common-Mode Rejection Ratio ? OPA2107 is 94db.

But, this time,

Important side is TL062's value. It's 86db.

This adjustment is very effective.

This adjustment is not in old IBVA.

I am searching a better OPA (for replace TL062). If it changes, I inform to you.

AD706 is 106db. But, AD706 is not good. (more 2.5mA per channnel is necessary for stability.)

Input Noise:

voltage noise

fB = 10 Hz to 10 KHz -> 0.6 ￢μ Vrms .. 0.7 ￢μVrms --> 0.85 ￢μ Vrms

fB = 0.1 Hz to 10 Hz -> 1.2 ￢μ Vp-p .. 1.6 ￢μVp-p --> 1.2 ￢μ Vrms

Current noise:

fB = 0.1 Hz to 10 Hz -> 12 fAp-p .. 15 fAp-p.  --> 23 fAp-p

fo = 0.1 Hz to 20 KHz -> 0.6 fA/*Hz .. 0.8 fA/*Hz --> 1.2 fA/*Hz

Input Noise that depend on source impedance at 10 Hz:

10M ohm: 400 nV/*Hz, fB = 0.1 Hz .. 10 Hz -> 7.5￢μ Vp-p --> There is not graph in pdf. 1 M ohm: 120 nV/*Hz, fB = 0.1 Hz .. 10 Hz -> 2.4 ￢μ Vp-p --> There is not graph in pdf.

100 K ohm: 50n nV/*Hz, fB = 0.1 Hz .. 10 Hz -> 1.2￢μ Vp-p --> There is not graph in pdf.

variable high cut frequency filter amplifier  Max 900 Hz -3bd. --

There is another hi-cut filter.

Amp's cut-off is about 1.5KHz (-3db), even in the case that there is not a variable filter.

Yes. 16V to 6V (5.6 is ok)

Digital side:

10 bit AD convertor 120 to 1960 sample par second.

minimum input 0 micro V p-p generate number 0.

max. input 200 micro V p-p generate number 1024.

minimum digital resolution is 200 micro V p-p / 1024 = 0.1953125 micro V p-p generate number 1.

Radio frequency: Bluetooth Interface class 2

2400 - 2483.5 MHz for USA/Europe/Japan

2446.5 to 2483.5 MHz France

Electrode side:

we can get good signal even if skin and electrode impedance changed between 0 to 100 K ohm then 0.4 micro V p-p out put noise. this mean we can use different electrode easily.

Power:

one 9V battery operate about 1 to 2 hours.

16 V to 6 V is works.

Order parts:

electrodes option sale as separately.

masahiro kahata

Psychic Lab, Inc.

m@psychiclub.com