URGENT!! the circuit of caculate our body resistance for BIA

[lee kf]

hello everyone.. can u help me to measure current by using PIC 16F8777A?? THE MOST IMPORTANT IS HOW TO BUILD A CIRCUIT TO MEASURE BODY RESISTANCE FOR BIA METHOD???????????????????? i m going to design a device to measure fatness in our body.. by using a formula which including our weight,height,sex(men or women),age as well as resistance in our body.this we call BIOELECTRICAL IMPEDANCE ANALYSIS.. so, it came out to my mind to measure the resistance by using voltage divider.. any of u have done this project??

 

[KMoffett]

Re: URGENT!! the circuit of caculate our body resistance for

You would need to make the body as a resistor in a Half- or Wheatstone-bridge driven by an AC voltage source. The output of the bridge would probably need to be amplified. Then it would need to be rectified and filtered, to obtain a DC voltage that the PIC could read. This is just a block diagram concept. I have no idea about the frequency of AC that is used to measure BIA "impedance".

Ken