# Purdue School of Engineering and Technology

## Biomedical Engineering

### Biomeasurements

#### BME 22200 / 4 Cr. (Two 75-minute Class, One 3-hour Lab)

The foundations of circuit theory are developed.  Electrical circuits are used in the context of biomedical applications including transducers, electrodes and the amplification and filtering of clinically relevant bioelectric signals.  Laboratory exercises develop technical skills in the design and analysis of analog Electrical circuits, signal processing and digital data acquisition and their safe use for biomeasurements.

##### Textbooks

Circuits, Signals, and Systems for Bioengineers. J. Semmlow. 2005. ISBN 0120884933 Medical Physiology. W. Boron and E. Boulpaep. 2nd Edition. ISBN 9781416031154

##### Outcomes

Upon completion of the course, students should be able to:

• Solve problems using basic principles, conventions, and procedures involving voltages, currents, and power.
• Describe circuit elements using their I-V relationships including resistors, dependent sources, capacitors, and inductors.
• Solve problems using Ohm’s Law, Kirchhoff’s Voltage Law, and Kirchhoff’s Current Law.
• Solve problems using basic techniques such as current division, voltage division, node-voltage analysis, mesh analysis, and superposition.
• Solve biological/physiology measurement problems based on basic impedance characteristics of tissues/cells.
• Determine the transient response and steady state response of first-order RL and RC circuits.
• Determine the transient and steady state response of second-order RLC circuits.
• Determine the steady state response to sinusoidal inputs and work in the phasor domain.
• Analyze circuits that use operational amplifiers.
• Discuss methods and special considerations involved in making measurements from living systems
• Describe the basic concepts and motivations behind design of electronic filters for analog signal conditioning.
• Discuss critical power issues in medical devices.
• Estimate long-term power use in implantable therapeutic devices.
• Describe microelectrodes and their interface to cell membranes in terms of their RC circuit properties.
• Perform experiments on living and nonliving electrical systems.
##### Topics

Brief list of topics to be covered:

Ohm’s and Kirchoff’s Laws applied to biomeasurements

Transformation and superposition

Resistive and reactive elements

Instantaneous and average power

AC impedance

Laboratory projects:

• Laboratory introduction: essential analog electronic elements, laboratory equipment and data acquisition hardware and software
• Exploration of Ohm’s law, the voltage divider, step and sinusoidal responses of series RC circuits
• Exploration of silicon diodes, step and sinusoidal response of series RL circuits
• Exploration of the steady-state frequency response of series RC and RL circuits and the transient response of series RLC circuits
• Nodal and mesh analysis in the exploration of Kirchhoff’s voltage and current laws
• Exploration of the steady-state frequency response of series and parallel RLC circuits – resonance
• Practical characterization of passive RC filters – low, high, and band pass of differing order
• Practical characterization of passive RLC filters – low, high, band pass, and notch of differing order
• Performance characterization of inverting and noninverting operational amplifier circuits: gain-bandwidth product, analog integrator and differentiator circuits, active filters of differing order and pass band characteristics