RX-8025SA Real-Time Clock Modules Epson Timing RX-8025SA Real-Time Clock Modules feature a 0.48µA backup current and 1.7V to 5.5V voltage range. RX-8025SA modules have a built-in 32.7kHz crystal unit, I2C-Bus interface, and numerous functions, including power supply voltage monitoring, stop detection, full calendar, and dual alarm. Epson Timing RX-8025SA Real-Time Clock Modules operate in the -40°C to +85°C temperature range.