描述 Description

The 'ABTH162260 are 12-bit to 24-bit multiplexed D-type latches used in applications where two separate data paths must be multiplexed onto, or demultiplexed from, a single data path. Typical applications include multiplexing and/or demultiplexing of address and data information in microprocessor or bus-interface applications. These devices are also useful in memory-interleaving applications. Three 12-bit I/O ports (A1-A12, 1B1-1B12, and 2B1-2B12) are available for address and/or data transfer. The output-enable (OE1B\\, OE2B\\, and OEA\\) inputs control the bus-transceiver functions. The OE1B\\ and OE2B\\ control signals also allow bank control in the A-to-B direction. Address and/or data information can be stored using the internal storage latches. The latch-enable (LE1B, LE2B, LEA1B, and LEA2B) inputs are used to control data storage. When the latch-enable input is high, the latch is transparent. When the latch-enable input goes low, the data present at the inputs is latched and remains latched until the latch-enable input is returned high. The B-port outputs, which are designed to sink up to 12 mA, include equivalent 25-series resistors to reduce overshoot and undershoot.Active bus-hold circuitry is provided to hold unused or floating data inputs at a valid logic level. When VCC is between 0 and 2.1 V, the device is in the high-impedance state during power up or power down. However, to ensure the high-impedance state above 2.1 V, 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. The SN54ABTH162260 is characterized for operation over the full military temperature range of -55°C to 125°C. The SN74ABTH162260 is characterized for operation from -40°C to 85°C.

特性 Features

? Members of the Texas InstrumentsWidebusTM Family
? B-Port Outputs Have Equivalent 25-Series Resistors, So No External Resistors Are Required
? State-of-the-ArtEPIC-II BTM BiCMOS Design Significantly Reduces Power Dissipation
? ESD Protection Exceeds 2000 V Per MIL-STD-883, Method 3015; Exceeds 200 V Using Machine Model (C = 200 pF, R = 0)
? Latch-Up Performance Exceeds 500 mA Per JEDEC Standard JESD-17
? Typical VOLP (Output Ground Bounce) CC = 5 V, TA = 25°C
? High-Impedance State During Power Up and Power Down
? Distributed VCC and GND Pin Configuration Minimizes High-Speed Switching Noise
? Flow-Through Architecture Optimizes PCB Layout
? Bus Hold on Data Inputs Eliminates the Need for External Pullup/Pulldown Resistors
? Package Options Include Plastic 300-mil Shrink Small-Outline (DL) Package 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.