Add a decoupling capacitor from VCC to
GND. The capacitor needs to be placed physically close to the device and
electrically close to both the VCC and GND pins. An example layout is
shown in the Layout.
Verify that the capacitive load at the output is
≤ 70pF. This value is not a hard limit, however,
considering this value helps achieve optimal
performance. This behavior can be accomplished by
providing short, appropriately sized traces from
the SN74HCS09 to the receiving device.
Verify that the resistive load at the output is
larger than (VCC / IO(max))Ω
so that the maximum output current from the
Absolute Maximum Ratings is not violated.
Most CMOS inputs have a resistive load measured in
megaohms; much larger than the minimum calculated
above.
Thermal issues are rarely a concern for logic
gates, however the power consumption and thermal
increase can be calculated using the steps
provided in the application note, CMOS Power Consumption and Cpd
Calculation