SN54ABT16833, SN74ABT16833
DUAL 8-BIT TO 9-BIT PARITY BUS TRANSCEIVERS

SCBS097D - FEBRUARY 1991 - REVISED JANUARY 1997

Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of TexasInstruments semiconductor products and disclaimers thereto appears at the end of this data sheet.

features

• Members of the Texas Instruments Widebus^TM Family
• State-of-the-Art EPIC-IIB^TM BiCMOS Design Significantly Reduces Power Dissipation
• Latch-Up Performance Exceeds 500 mA Per JEDEC Standard JESD-17
• Typical V_OLP (Output Ground Bounce) < 1 V at V_CC = 5 V, T_A = 25°C
• Distributed V_CC and GND Pin Configuration Minimizes High-Speed Switching Noise
• Flow-Through Architecture Optimizes PCB Layout
• High-Drive Outputs (-32-mA I_OH, 64-mA I_OL)
• Parity-Error Flag With Parity Generator/Checker
• Register for Storage of Parity-Error Flag
• Package Options Include Plastic 300-mil Shrink Small-Outline (DL) and Thin Shrink Small-Outline (DGG) Packages and 380-mil Fine-Pitch Ceramic Flat (WD) Package Using 25-mil Center-to-Center Spacings

  Widebus and EPIC-IIB are trademarks of Texas Instruments Incorporated.

description

The 'ABT16833 consist of two noninverting 8-bit to 9-bit parity bus transceivers and are designed for communication between data buses. For each transceiver, when data is transmitted from the A bus to the B bus, an odd-parity bit is generated and output on the parity I/O pin (1PARITY or 2PARITY). When data is transmitted from the B bus to the A bus, 1PARITY (or 2PARITY) is configured as an input and combined with the B-input data to generate an active-low error flag if odd parity is not detected.

The error (1 or 2) output is configured as an open-collector output. The B-to-A parity-error flag is clocked into 1 (or 2) on the low-to-high transition of the clock (1CLK or 2CLK) input. 1 (or 2) is cleared (set high) by taking the clear (1 or 2) input low.

The output-enable ( and) inputs can be used to disable the device so that the buses are effectively isolated. When both and are low, data is transferred from the A bus to the B bus and inverted parity is generated. Inverted parity is a forced error condition that gives the designer more system diagnostic capability.

To ensure the high-impedance state during power up or power down, 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.

The SN54ABT16833 is characterized for operation over the full military temperature range of -55°C to 125°C. The SN74ABT16833 is characterized for operation from -40°C to 85°C.