An electronic device for data processing is disclosed having a CPU (3), a Closely Coupled Memory (5), an external memory system (8), and a first clock unit (1) and second clock unit (9) for receiving a main clock signal (2) and converting the main clock signal (2) into a first clock signal (6) for at least the Central Processing Unit (3) and Closely Coupled Memory (5) and a second clock signal (10) for the external memory (8). The first clock signal has a first clock frequency and the second clock signal has a second clock frequency being higher than said first clock frequency and wherein the device is configured to switch per time unit the external memory for an active period Tactive in an active state and for a standby period Tstandby in a standby state to retrieve a predetermined amount of data from the external memory per time unit.