SN74ACT1284是TI公司的一款IEEE-1284并行端接口(PPI)产品，SN74ACT1284是具有三态输出的 7 位总线接口，本页介绍了SN74ACT1284的产品说明、应用、特性等，并给出了与SN74ACT1284相关的TI元器件型号供参考。
SN74ACT1284 - 具有三态输出的 7 位总线接口 - IEEE-1284并行端接口(PPI) - 特殊逻辑 - TI公司（Texas Instruments，德州仪器）
The ’ACT1284 devices are designed for asynchronous two-way communication between data buses. The control function minimizes external timing requirements.
The devices allow data transmission in either the A-to-B or the B-to-A direction for bits 1, 2, 3, and 4, depending on the logic level at the direction-control (DIR) input. Bits 5, 6, and 7, however, always transmit in the A-to-B direction.
The output drive for each mode is determined by the high-drive (HD) control pin. When HD is high, the high drive is delivered by the totem-pole configuration, and when HD is low, the outputs are open drain. This meets the drive requirements as specified in the IEEE 1284-I (level-1 type) and the IEEE 1284-II (level-2 type) parallel peripheral-interface specification.
- 4.5-V to 5.5-V VCC Operation
- Inputs Accept Voltages to 5.5 V
- Max tpd of 20 ns at 5 V
- 3-State Outputs Directly Drive Bus Lines
- Flow-Through Architecture Optimizes PCB Layout
- Center-Pin VCC and GND Configurations Minimize High-Speed Switching Noise
- ESD Protection Exceeds JESD 22
- 2000-V Human-Body Model (A114-A)
- 200-V Machine Model (A115-A)
- Designed for the IEEE 1284-I (Level-1 Type) and IEEE 1284-II (Level-2 Type) Electrical Specifications
