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Details, datasheet, quote on part number:SN74ALVCH16646DLR
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Datasheet text preview:
SN74ALVCH16646 16-BIT BUS TRANSCEIVER AND REGISTER WITH 3-STATE OUTPUTS
SCES032E JULY 1995 REVISED FEBRUARY 1999
D D D D D D
Member of the Texas Instruments Widebus TM Family EPIC TM (Enhanced-Performance Implanted CMOS) Submicron Process 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 250 mA Per JESD 17 Bus Hold on Data Inputs Eliminates the Need for External Pullup/Pulldown Resistors Package Options Include Plastic 300-mil Shrink Small-Outline (DL), Thin Shrink Small-Outline (DGG), and Thin Very Small-Outline (DGV) Packages
DGG, DGV, OR DL PACKAGE (TOP VIEW)
description
This 16-bit bus transceiver and register is designed for 1.65-V to 3.6-V VCC operation. The SN74ALVCH16646 can be used as two 8-bit transceivers or one 16-bit transceiver. Data on the A or B bus is clocked into the registers on the low-to-high transition of the appropriate clock (CLKAB or CLKBA) input. Figure 1 illustrates the four fundamental bus-management functions that can be performed with the SN74ALVCH16646.
Output-enable (OE) and direction-control (DIR) 28 29 inputs are provided to control the transceiver functions. In the transceiver mode, data present at the high-impedance port may be stored in either register or in both. The select-control (SAB and SBA) inputs can multiplex stored and real-time (transparent mode) data. The circuitry used for select control eliminates the typical decoding glitch that occurs in a multiplexer during the transition between stored and real-time data. DIR determines which bus receives data when OE is low. In the isolation mode (OE high), A data may be stored in one register and/or B data may be stored in the other register. When an output function is disabled, the input function is still enabled and may be used to store and transmit data. Only one of the two buses, A or B, can be driven at a time. To ensure the high-impedance state during power up or power down, 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. Active bus-hold circuitry is provided to hold unused or floating data inputs at a valid logic level. The SN74ALVCH16646 is characterized for operation from 40°C to 85°C.
1DIR 1CLKAB 1SAB GND 1A1 1A2 VCC 1A3 1A4 1A5 GND 1A6 1A7 1A8 2A1 2A2 2A3 GND 2A4 2A5 2A6 VC C 2A7 2A8 GND 2SAB 2CLKAB 2DIR
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27
56 55 54 53 52 51 50 49 48 47 46 45 44 43 42 41 40 39 38 37 36 35 34 33 32 31 30
1OE 1CLKBA 1SBA GND 1B1 1B2 VC C 1B3 1B4 1B5 GND 1B6 1B7 1B8 2B1 2B2 2B3 GND 2B4 2B5 2B6 VC C 2B7 2B8 GND 2SBA 2CLKBA 2OE
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet. EPIC and Widebus are trademarks of Texas Instruments Incorporated.
PRODUCTION DATA information is current as of publication date. Products conform to specifications per the terms of Texas Instruments standard warranty. Production processing does not necessarily include testing of all parameters.
Copyright © 1999, Texas Instruments Incorporated
POST OFFICE BOX 655303
· DALLAS, TEXAS 75265
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SN74ALVCH16646 16-BIT BUS TRANSCEIVER AND REGISTER WITH 3-STATE OUTPUTS
SCES032E JULY 1995 REVISED FEBRUARY 1999
FUNCTION TABLE INPUTS OE X X H H L L L L DIR X X X X L L H H CLKAB X H or L X X X H or L CLKBA X H or L X H or L X X SAB X X X X X X L H SBA X X X X L H X X Input Unspecified Input Input disabled Output Output Input Input DATA I/Os A1A8 B1B8 Unspecified Input Input Input disabled Input Input Output Output OPERATION OR FUNCTION OR FUNCTION Store A, B unspecified Store B, A unspecified Store A and B data Isolation, hold storage Real-time B data to A bus Stored B data to A bus Real-time A data to B bus
Stored A data to B bus The data-output functions may be enabled or disabled by various signals at OE and DIR. Data-input functions always are enabled; i.e., data at the bus terminals is stored on every low-to-high transition of the clock inputs.
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POST OFFICE BOX 655303
· DALLAS, TEXAS 75265
SN74ALVCH16646 16-BIT BUS TRANSCEIVER AND REGISTER WITH 3-STATE OUTPUTS
SCES032E JULY 1995 REVISED FEBRUARY 1999
BUS B
OE L
DIR L
CLKAB CLKBA X X
SAB X
SBA L
OE L
DIR H
CLKAB X
CLKBA X
SAB L
BUS B SBA X REAL-TIME TRANSFER BUS A TO BUS B CLKAB X H or L CLKBA H or L X SAB X H BUS B SBA H X TRANSFER STORED DATA TO A AND/OR B
BUS A
REAL-TIME TRANSFER BUS B TO BUS A
BUS B
BUS A
OE X X H
DIR X X X
CLKAB CLKBA X X STORAGE FROM A, B, OR A AND B
SAB X X X
SBA X X X
OE L L
Figure 1. Bus-Management Functions
POST OFFICE BOX 655303
· DALLAS, TEXAS 75265
BUS A DIR L H
BUS A
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