This glucose meter is an efficient, user-friendly tool for real-time blood glucose monitoring, combining accuracy, storage capabilities, and practical features to support diabetes management.
A glucose meter is a medical device used to measure glucose concentration in a solution, expressed in milligrams per deciliter (mg/dL) or millimoles per liter (mmol/L), depending on regional standards. It is an essential component of Home Blood Glucose Monitoring (HBGM) systems for individuals with diabetes mellitus, enabling them to manage their condition through multiple daily measurements. The device provides critical data for effective glucose management. Glucose meters primarily operate using electrochemical technology, relying on disposable test strips. A small drop of solution applied to the strip allows glucose measurement through either the colorimetric or amperometric method.
The glucose meter AN1560 reference design by Microchip Technology is designed to measure glucose concentrations ranging from 20 mg/dL to 600 mg/dL (1 mmol/L to 33 mmol/L), with results displayed within five seconds. It can automatically store up to 32 readings, complete with date and time stamps, eliminating the need for test strip coding by utilizing a generic, adjustable regression equation. The hardware design includes a single-board system powered by a PIC16LF178X microcontroller with a 28-pin configuration. Programming and debugging are enabled through an In-Circuit Serial Programming™ (ICSP™) connection. Additional hardware features include test strip connectors, a Real-Time Clock Calendar (RTCC) for timestamping, and internal EEPROM for storing readings, calibration data, and test strip parameters.
The device features an LCD that displays glucose levels in mg/dL or mmol/L and provides messages like “Insert Test Strip,” “Place the Sample,” or “Faulty Test Strip.” It also includes test strip sensing to detect insertion, temperature sensing to adjust for glucose variations due to temperature changes, and battery health monitoring with low battery alerts. Two push buttons allow users to access stored readings or set the date and time, and the device is powered by a 3V CR2032 lithium battery with a capacity of 225 mAh.
The firmware of the glucose meter harnesses the capabilities of the PIC16LF178X microcontroller to execute measurements and manage device operations. It detects the test strip current using internal op-amp, DAC, and ADC modules, and confirms strip insertion by monitoring for a voltage rise above 450 mV. Once a sample is applied, ADC data is recorded 1.5 seconds later, and the average is used to calculate glucose concentration via a regression equation. Firmware modules handle LCD interface routines, sensor configuration, EEPROM data storage, ADC reading, and RTCC implementation for timestamping.
Microchip Technology tests it, including system block diagrams, schematics, and PCB design files. This ensures users have access to all necessary resources for implementing, evaluating, and customising the solution. It features a robust power system based on high-performance components, ensuring reliability and efficiency.For more information, click here.
