Patent ID: 6335866
Filing Date: 2002-01-01
Classification: H05K

Abstract:
A printed wiring board unit for use with an electronic apparatus formed of a power circuit, an analog circuit and a plurality of digital circuits which operate respectively at different frequencies said printed wiring board unit comprising:a second printed wiring board which constitutes only digital circuits, said second printed wiring board having mounted thereon at least a first digital IC which operates at the highest internal clock frequency within said printed wiring board unit and a second digital IC which operates in synchronization with the first digital IC, and said ICs being formed into a module; a first printed wiring board which constitutes a power circuit, an analog circuit, and a digital circuit which operates at a frequency differing from that of the digital circuit mounted on said second printed wiring board, said first printed wiring board being a single-sided board and being formed larger than said second printed wiring board; and means for permanently mounting said second printed wiring board onto said first printed wiring board in a layered structure.