9.1 Overview

The SN74AHCT16245 device is a 16-bit (dual-octal) noninverting 3-state transceiver designed for synchronous two-way communication between data buses. The control-function implementation minimizes external timing requirements.

This device can be used as two 8-bit transceivers or one 16-bit transceiver. It allows data transmission from the A bus to the B bus or from the B bus to the A bus, depending on the logic level at the direction-control (DIR) input. The output-enable (OE) input can be used to disable the device so that the buses are effectively isolated.

To ensure the high-impedance state during power up or power down, OE should be tied to V_CC through a pullup resistor; the minimum value of the resistor is determined by the current-sinking capability of the driver.

9.2 Functional Block Diagrams

A. † This symbol is in accordance with ANSI/IEEE Std 91-1984 and IEC Publication 617-12.

Figure 3. Logic Symbol

Figure 4. Logic Diagram (Positive Logic)

9.3 Feature Description

• TTL inputs
  • Lowered switching threshold allows up translation 3.3 V to 5 V
• Slow edges reduce output ringing

9.4 Device Functional Modes