Patent ID: 6052021
Filing Date: 2000-04-18
Classification: G06J

Abstract:
A signal processing integrated circuit comprising:a) analog signal processing means for processing an analog signal;b) digital signal processing means for transmitting first signals to and receiving second signals from said analog signal processing means through a first path and a second path, respectively, and for processing a digital signal, said first and second paths extending between said analog signal processing means and said digital signal processing means, said analog signal processing means and said digital signal processing means each including transistors which are formed on a common substrate of said integrated circuit;c) power supply wiring and terminals for separately supplying power to said analog signal processing means and to said digital signal processing means so that said analog and digital processing means transistors are powered at separate terminals while respective predetermined power source voltages are supplied to each of said analog signal processing means and said digital signal processing means; andd) first buffer means connected in said first path between said digital signal processing means and said analog signal processing means and second buffer means connected in said second path between said analog signal processing means and said digital signal processing means, said buffer means being constructed to prevent current which is greater than a given magnitude from flowing through said paths at least upon the application of power source voltages to said power supply wiring and terminals.