Title :
Characteristics of the Howland current source for bioelectric impedance measurements systems
Author :
Yazdanian, Hassan ; Samani, Mohsen Mosayebi ; Mahanm, Amin
Author_Institution :
Dept. of Biomed. Eng., Univ. of Isfahan, Isfahan, Iran
Abstract :
In the development of bioelectric impedance measuring systems, design of a stable current source with broad bandwidth and high output impedance is an important consideration. Howland circuit is a well known high performance, voltage controlled current source which can provide high output impedance as well as high frequency bandwidth. This paper presents a detailed study of Howland current source by considering the non-ideal characteristics of the components. Two different forms of Howland current source are compared and resulted relationship were evaluated by simulations. The results of this study facilitate the design of Howland circuit for bioelectric impedance measurement systems.
Keywords :
bioelectric phenomena; biomedical measurement; constant current sources; electric impedance measurement; plethysmography; Howland circuit; Howland current source; bioelectric impedance measurements systems; high frequency bandwidth; high output impedance; impedance plethysmography; impedance spectroscopy; stable current source; Current measurement; Equations; Impedance; Impedance measurement; Mathematical model; Resistors; Standards; Bioelectric impedance; Current Source; Howland circuit; Impedance Plethysmography; Impedance Spectroscopy;
Conference_Titel :
Biomedical Engineering (ICBME), 2013 20th Iranian Conference on
Conference_Location :
Tehran
DOI :
10.1109/ICBME.2013.6782216
