MIKROE-2998 Heart Rate 7 Click Mikroe MIKROE-2998 Heart Rate 7 Click is an optical biosensor Click Board™ designed for Heart-Rate Monitoring (HRM). This click board employs a very sensitive analog front-end IC with a high dynamic range, which ensures accurate and reliable readings. This analog front-end IC is coupled with the optical front-end, which consists of a sensitive Photo-Diode (PD) and two high-brightness green LEDs. Mikroe MIKROE-2998 Heart Rate 7 Click provides highly accurate HRM readings as the photo-diode is most sensitive to visible light and offers reasonably high current output.