Design of a Low-Cost Galvanic Skin Response Stress Monitoring System Using PIC16F688

Abstract Mental stress has become a major health problem, directly linked to cardiovascular disease, chronic anxiety, and immune system issues [1]. Catching acute stress early allows people to intervene before it impacts their health [2]. This paper covers the design and practical build of an ultra-low-cost, non-invasive Galvanic Skin Response stress monitoring device built around the Microchip PIC16F688 8 bit microcontroller [3]. The system works by reading tiny changes in skin conductance caused by sweat gland activity, which is directly controlled by the sympathetic nervous system[1][4].An analog signal conditioning circuit converts high impedance skin resistance changes into a clean voltage range given as input for the PIC16F688 internal 10 bit Analog to Digital Converter[3]. The microcontroller runs moving average filtering and threshold based classification right on the chip. Testing shows the prototype reliably tells the difference between relaxed, baseline, and high stress states in real time, keeping power consumption minimal and the total component cost extremely low.