TWO-STAGE POWER NOISE FILTER

• Main Authors: FRECH ROLAND DR, WINKEL THOMAS-MICHAEL, SHUTLER WILLIAM, WEISS ULRICH, KLINK ERICH
• Format: Patent
• Language: English
• Published: 24.12.1999
• Edition: 6
• Subjects: AUTOMATIC CONTROL, STARTING, SYNCHRONISATION, OR STABILISATIONOF GENERATORS OF ELECTRONIC OSCILLATIONS OR PULSES; BASIC ELECTRIC ELEMENTS; BASIC ELECTRONIC CIRCUITRY; CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES ORLIGHT-SENSITIVE DEVICES, OF THE ELECTROLYTIC TYPE; ELECTRIC COMMUNICATION TECHNIQUE; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; SEMICONDUCTOR DEVICES; TRANSMISSION

PROBLEM TO BE SOLVED: To reduce power noise by connecting a first low pass filter which has an off-chip capacitance and filtrates intermediate-frequency power noise, and a second low pass filter which has an on-chip capacitance and filtrates high-frequency power noise in series. SOLUTION: A first low pass filter which filtrates intermediate-frequency power noise having a frequency of 10-100 MHz is composed of an off-chip capacitance 2, an on-chip resistor R16 which connects a voltage surface VDD to an in-chip node 18, and thin film wiring 8 in the uppermost layer of a multilayered thin film. A second low pass filter which filtrates high-frequency power noise is composed of an on-chip capacitance 12 and an on-chip resistor 7. The first and second low pass filters are connected in series. The first low pass band stage backs up the low induced charge of the capacitance 12 of the second low pass filter and the second low pass band stage becomes the low induced current source of a voltage-controlled device.