A Transconductance Driven Right Leg Circuit

E. SPINELLI; N. MARTINEZ; M. MAYOSKY

IEEE TRANSACTIONS ON BIO-MEDICAL ENGINEERING

IEEE

Año: 1999 vol. 46 p. 1466 - 1471

0018-9294

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.