SN74ALS521 8-Bit Identity/Magnitude Comparators (P=Q) with Enable |

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8-Bit Identity/Magnitude Comparators (P=Q) with Enable

8-Bit Identity/Magnitude Comparators (P=Q) with Enable - SN74ALS521


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.

The SN54ALS520 is characterized for operation over the full military temperature range of -55°C to 125°C. The SN74ALS518, SN74ALS520, and SN74ALS521 are characterized for operation from 0°C to 70°C.




  • 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



SN74ALS521 is identical to ´ALS688.


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Part number Order Technology Family VCC (Min) (V) VCC (Max) (V) Bits (#) Voltage (Nom) (V) F @ nom voltage (Max) (MHz) ICC @ nom voltage (Max) (mA) tpd @ nom Voltage (Max) (ns) IOL (Max) (mA) IOH (Max) (mA) Operating temperature range (C) Package Group
SN74ALS521 Order now ALS     4.5     5.5     8     5.5     75     19     22     24     -2.6     0 to 70     PDIP | 20
SOIC | 20
SO | 20