How much total current can be drawn from a typical 74HC device? I see specs that state the ground current cannot exceed 50mA and other specs that say the device dissipation is limited to 750mW. Most of the specs say that 25mA can be had from any one output, but it's hard to figure out the total for several outputs.
For example, the 74HC164 shift register is speced at 25mA per output pin, but only a total of 50mA for the ground pin. Does that mean the maximum output current for any one pin is limited to 6mA if all 8 outputs are loaded at the same time?