Apparatus and method for measuring bioelectric impedance
US6292690A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 12, 2000 |
| Grant date | Sep 18, 2001 |
| Priority date | — |
| Expiry date | Jan 12, 2020 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61B5/0537
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
A circuit for measuring body impedance comprising a voltage source having a predetermined frequency and a current source; a first pair of electrodes adapted to receive one portion of the body for applying said current source to said body; a second pair of electrodes adapted to receive another portion of the body for sensing a voltage therebetween; a comparator having first and second inputs and an output for producing an output signal based on signals applied to said first and second inputs; an instrumentation amplifier arrangement coupled to one of said comparator inputs and responsive to the voltage across the second pair of electrodes for providing an input signal to said first comparator input; a variable resistor coupled to the second input of said comparator and responsive to said voltage source for developing a first voltage signal applied to said second comparator input; and a processor responsive to the output signal of the comparator for controlling the resistance of the variable resistor to cause a corresponding change in said first voltage, whereby when said voltage at said first input corresponds to the voltage at said second input of said comparator; said comparator o…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.