SN74AHC244QDWRQ1
八路缓冲器/驱动器,具有三态输出 OCTAL BUFFER/DRIVER WITH 3-STATE OUTPUTS
This octal buffer/driver is designed specifically to improve the performance and density of 3-state memory-address drivers, clock drivers, and bus-oriented receivers and transmitters.
The SN74AHC244 is organized as two 4-bit buffers/line drivers with separate output-enable OE inputs. When OE is low, the device passes data from the A inputs to the Y outputs. When OE is high, the outputs are in the high-impedance state.
To ensure the high-impedance state during power up or power down, OE should be tied to VCC through a pullup resistor; the minimum value of the resistor is determined by the current-sinking capability of the driver.