Da converter

Abstract

Abstract PURPOSE:To prevent an output waveform from being distorted owing to the amplitude attenuation of a high-frequency component due to the aperture effect that a DA converting circuit has by correcting the aperture effect by a digital filter incorporated in the same semiconductor substrate or a digital filter packaged in the same package. CONSTITUTION:This converter consists of a digital high-pass filter 1-5 and a DA converting circuit 1-1. Then the filter 1-5 consists of a delay circuit 1-2 which delays a digital signal by its sampling period T, an adding circuit 1-3 which adds plural digital signals, and a coefficient multiplying circuit 1-4 which multiplies the digital signal by a coefficient. In this constitution, the amplitude characteristic F(omega) of the filter 1-5 can be approximated by an equation in a frequency range a half (fs/2) as high as the sampling frequency fs=1/T of the frequency characteristic F(omega) of the filter 1-5, and consequently the aperture effect of the DA converter can be corrected.

Inventors

• 👤 Tomoji Takada
• 👤 高田　知二

Bibliographic Details