Microcomputer for controlling domestic equipment - with noise protection provided by low pass filter circuit coupled across oscillator

摘要

The micro computer (1) has a pair of clock signal inputs (3, 5) and an earth connection (7). The earth connectors is coupled directly to the ground line (11) via a low impedance part. The clock inputs connect to a quarz oscillator (15) and each line has a capacitor (17, 19) connection to a resistor (23) connected to ground. The resistor which is approximately 1 kohm and the capacitors of 10-50 pF, form a low pass filter that suppress the high frequency noise signals (25). ADVANTAGE - Improves protection against noise.