Lock-in Amplifier for myRIO
This application uses the myRIO-1900 to implement a lock-in amplifier in the FPGA. The application measures a modulated signal and a reference signal, which can also be generated with myRIO. The lock-in amplifier can measure very low level input signals, even if they are buried in noise or are smaller than myRIO’s 12-bit resolution. The lock-in amplifier includes a selectable high-pass filter to remove any input DC offset, and also includes a programmable output low pass filter that removes any noise beyond the frequencies of interest. The application is geared towards education and understanding the principles of a lock-in amplifier. It includes extensive documentation and instructions for building a circuit to measure heart rate by using an LED and photodiode amplifier to measure the amount of light absorbed through the blood vessels in a finger.
Download[/et_pb_text][/et_pb_column][et_pb_column type=”1_3″][et_pb_image admin_label=”Image” src=”http://delacor.com/wp-content/uploads/2014/06/LIA_myRIOBoard1.jpg” show_in_lightbox=”off” url_new_window=”off” animation=”top” /][et_pb_text admin_label=”Text” background_layout=”light” text_orientation=”left”]
[/et_pb_text][/et_pb_column][/et_pb_row][et_pb_row][et_pb_column type=”4_4″][et_pb_divider admin_label=”Divider” color=”#cccccc” show_divider=”on” /][/et_pb_column][/et_pb_row][et_pb_row][et_pb_column type=”1_3″][et_pb_image admin_label=”Image” src=”http://delacor.com/wp-content/uploads/2014/06/myRIOAccessory.jpg” show_in_lightbox=”off” url_new_window=”off” animation=”top” /][/et_pb_column][et_pb_column type=”2_3″][et_pb_text admin_label=”Text” background_layout=”light” text_orientation=”left”]Lock-in Amplifier Accessory for myRIO
This accessory is the fastest way to get started with the Lock-In Amplifier for myRIO add-on. The board includes a red LED to generate modulated light, and a photodiode and signal conditioning circuitry to measure the received signal. This accessory can be used for a variety of measurements, such as determining your heart rate. If you place your finger between the LED and photodiode, the Lock-In Amplifier will pick up the small difference in absorbed light as blood pumps in and out of the capillaries in your fingertip. The add-on uses this information to calculate heart rate. You can order the board with the configuration that best suits your measurements:
- LED and photodiode soldered on the board as shown in the image
- Loose LED and photodiode so you can attach them to your own fixture
- SMA Connectors for the reference output and 5V input signal.
If you would like a board with SMA connectors configured for current input, or for orders outside the US, please contact us at info@delacor.com.
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