54ACT16474, 74ACT16474
18-BIT REGISTERED BUS TRANSCEIVERS
WITH 3-STATE OUTPUTS

SCAS238A - MAY 1992 - REVISED APRIL 1996

features

• Members of the Texas Instruments Widebus^TM Family
• Inputs Are TTL-Voltage Compatible
• 3-State Outputs Drive Bus Lines Directly
• Flow-Through Architecture Optimizes PCB Layout
• Distributed V_CC and GND Pin Configurations Minimize High-Speed Switching Noise
• EPIC^TM (Enhanced-Performance Implanted CMOS) 1-m Process
• 500-mA Typical Latch-Up Immunity at 125°C
• Package Options Include Plastic 300-mil Shrink Small-Outline (DL) Packages Using 25-mil Center-to-Center Pin Spacings and 380-mil Fine-Pitch Ceramic Flat (WD) Packages Using 25-mil Center-to-Center Pin Spacings

EPIC and Widebus are trademarks of Texas Instruments Incorporated.

description

The 'ACT16474 are noninverting 18-bit registered bus transceivers composed of two 9-bit sections with separate control signals. For either 9-bit transceiver section, data flow in the A-to-B mode is controlled by output-enable (1 or 2) and clock (1CLKAB or 2CLKAB) inputs. When 1 or 2 is low, the corresponding outputs are active (high or low) and take on either the current data on low-to-high transition of 1CLKAB or 2CLKAB or the previously stored data if 1CLKAB or 2CLKAB is low.

When 1 or 2 is high, the corresponding outputs are in the high-impedance state. 1 or 2 does not affect the operation on the internal registers. Previously stored data can be retained or new data can be entered while the outputs are in the high-impedance state.

Data flow from B to A is similar, but uses 1 and/or 2 and 1CLKBA and/or 2CLKBA.

The 74ACT16474 is packaged in TI's shrink small-outline package, which provides twice the I/O pin count and functionality of standard small-outline packages in the same printed-circuit-board area.

The 54ACT16474 is characterized for operation over the full military temperature range of -55°C to 125°C. The 74ACT16474 is characterized for operation from -40°C to 85°C.