Is a bypass capacitor required between the VCC and GND terminals?

For IC couplers with built-in amplifier circuit, internal oscillation may occur for such a reason as VCC voltage transient owing to load switching or power supply noise. In order to prevent it and realize normal operation, Toshiba recommends inserting a 0.1μF bypass capacitor with good high-frequency characteristics between VCC and GND and mounting it within 1cm of the pins. For some gate driver IC couplers, in order to control an impact attributable to a large fluctuation of the output current, Toshiba recommends mounting an about 1 μF bypass capacitor. For details, refer to individual data sheets.