The figures found in this table illustrate the C8051F90x/91x’s various power modes and typical current consumptions with each. As can be seen here, the system becomes more efficient the longer it stays in sleep mode. The 50nA sleep currents with a 2µS wake-up time are very compelling numbers. Combine these numbers with the fast execution of the single cycle core and all of the autonomous peripherals result in a complete low power system on a chip solution from Silicon Labs.