SN54ALS520, SN74ALS518, SN74ALS520, SN74ALS521 8-BIT IDENTITY COMPARATORS SDAS224B - JUNE 1982 - REVISED NOVEMBER 1995 * TYPE SN74ALS518 INPUT PULLUP RESISTOR Yes G P0 Q0 P1 Q1 P2 Q2 P3 Q3 GND OUTPUT FUNCTION AND CONFIGURATION P = Q open collector ALS520 Yes P = Q totem pole SN74ALS521 No P = Q totem pole SN74ALS521 is identical to ALS688. 1 20 2 19 3 18 4 17 5 16 6 15 7 14 8 13 9 12 10 11 VCC P = Q / P = Q Q7 P7 Q6 P6 Q5 P5 Q4 P4 P = Q for SN74ALS518 P = Q for ALS520 and SN74ALS521 SN54ALS520 . . . FK PACKAGE (TOP VIEW) description Q0 P0 These identity comparators perform comparisons on two 8-bit binary or BCD words. The SN74ALS518 provides P = Q outputs, while the ALS520 and SN74ALS521 provide P = Q outputs. The SN74ALS518 has an open-collector output. The SN74ALS518 and ALS520 feature 20-k pullup resistors on the Q inputs for analog or switch data. P1 Q1 P2 Q2 P3 4 2 1 20 19 18 5 17 6 16 7 15 8 14 9 10 11 12 13 Q7 P7 Q6 P6 Q5 Q3 GND P4 Q4 P5 The SN54ALS520 is characterized for operation over the full military temperature range of - 55C to 125C. The SN74ALS518, SN74ALS520, and SN74ALS521 are characterized for operation from 0C to 70C. 3 P=Q * SN54ALS520 . . . J PACKAGE SN74ALS518, SN74ALS520, SN74ALS521 . . . DW OR N PACKAGE (TOP VIEW) Compare Two 8-Bit Words Choice of Totem-Pole or Open-Collector Outputs SN74ALS518 and ALS520 Have 20-k Pullup Resistors on Q Inputs Package Options Include Plastic Small-Outline (DW) Packages, Ceramic Chip Carriers (FK), and Standard Plastic (N) and Ceramic (J) 300-mil DIPs G VCC * * FUNCTION TABLE INPUTS OUTPUTS DATA P, Q ENABLE G P=Q P=Q L H L P>Q L L H P