禁止将多个输出连接在一起的线或逻辑,因为它们是短路的。显然,任何输出都不得连接到Vcc或GND。(Fig. 1)
Multiple gates in the same package can be connected together as shown below to increase the drive capability.
However, it is recommended to use high-drive ICs instead, such as the 74AC, 74LCX and 74VCX series.
In order to improve the drive capability, the gates in the same package can be connected as shown in Fig. 2. However, it is recommended to use a IC with high drive capability such as 74AC, 74LCX, 74VCX Series.
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