Output drive circuit

Abstract

Abstract PURPOSE:To decrease each noise increased attended with high performance of a large scale integrated circuit by providing a capacitive element between a gate of an MIS drive element at a low potential side of an output drive circuit and an output terminal. CONSTITUTION:The capacitive element 3 is provided between a common gate 30 of a C-MOS circuit of the final stage and the output terminal 14 so as to unsharpen the waveform at the output terminal. The capacitance value of the element 3 is regarded as (1+A) times equivalently viewed from the pre-stage, and a signal waveform at a section 31 shows a trailing decided by the time constant comprising the ON-resistance 32 of an N-MOS.FET28 and the capacitive element 3 when the level of an output terminal 2 of an auxiliary buffer goes from high to low level unsharpening (A is the amplification factor of final output buffer FETs 26, 29) an auxiliary output buffer at the leading and trailing waveform of the output waveform as shown in equivalent circuit (Fig. a). Then the element 3 is the said capacitance value. Then the waveform of the output terminal 14 is unsharpened proportional to the unsharpened waveform of the section 31. This is the same for the case when the level of the output terminal 2 goes from low to high level.

Inventors

• 👤 Kiyokazu Arai
• 👤 新井　喜代和
• 👤 Michio Asano
• 👤 浅野　道雄
• 👤 Kazuo Koide
• 👤 一夫 小出
• 👤 Akira Yamagiwa
• 👤 明 山際

Bibliographic Details