RFID circuitry is used in an endoscopic light source unit to track cumulative light bulb use information. An inductively powered RFID tag is affixed to the light bulb assembly, and communicates wirelessly with an RF transceiver within the light source unit via a low-frequency modulation wave. The RFID tag includes memory which stores a value representing cumulative duration of use of the light bulb. The transceiver reads the value from the RFID tag and communicates the value to control circuitry in the light source unit, which tracks use of the light bulb within the light source unit. Based on such tracking, the transceiver periodically updates the value in the RFID tag via the wireless link. Cumulative bulb usage hours is displayed on the light source unit. The RFID tag also may store a custom password and/or other information.