A transconductance driven-right-leg circuit.
Biopotential measurements are very sensitive to electromagnetic interference (EMI). EMI gets into the acquisition system by many ways, both as differential and common mode signals, driven-right-leg circuits (DRL) are widely used to reduce common mode interference. This paper reports an improvement on the classic DRL. The proposed circuit uses a transconductance amplifier to drive the patient's body. This configuration has some interesting properties, which provide an extended bandwidth for high-frequency EMI rejection (such as fluorescent lights interference). The improvement is around 20 dB for frequencies of few kilohertz and the circuit is easy to compensate for stability. A comparative analysis against a typical DRL is presented, the results obtained have been experimentally tested.
Spinelli
E M
EM
Industrial Electronics, Control and Instrumentation Laboratory (LEICI), Facultad de Ingeniería, Universidad Nacional de La Plata (UNLP) CC 91, Argentina. spinelli@venus.fisica.unlp.edu.ar
Martínez
N H
NH
Mayosky
M A
MA
D004553:Electric Conductivity; D004560:Electricity; D004594:Electrophysiology; D006801:Humans; D008962:Models, Theoretical; D011827:Radiation