{"id":7974,"date":"2026-06-28T06:17:44","date_gmt":"2026-06-28T06:17:44","guid":{"rendered":"https:\/\/materialparts.com\/sn74ls85n\/"},"modified":"2026-06-28T11:44:55","modified_gmt":"2026-06-28T11:44:55","slug":"sn74ls85n","status":"publish","type":"post","link":"https:\/\/materialparts.com\/ar\/sn74ls85n\/","title":{"rendered":"SN74LS85N"},"content":{"rendered":"

\u0646\u0638\u0631\u0629 \u0639\u0627\u0645\u0629 \u0639\u0644\u0649 \u0627\u0644\u0645\u0646\u062a\u062c<\/h2>\n

The SN74LS85N from Texas Instruments is a 4-bit magnitude comparator that determines whether one 4-bit binary number is greater than, less than, or equal to another, with cascading inputs for comparing numbers wider than 4 bits in a 16-pin PDIP package.<\/p>\n

\u0627\u0644\u0645\u0648\u0627\u0635\u0641\u0627\u062a \u0627\u0644\u0631\u0626\u064a\u0633\u064a\u0629<\/h2>\n\n\n\n\n\n\n\n\n\n\n
\u0627\u0644\u0648\u0638\u064a\u0641\u0629<\/td>\n4-bit magnitude comparator<\/td>\n<\/tr>\n
\u0639\u0627\u0626\u0644\u0629 \u0627\u0644\u0645\u0646\u0637\u0642<\/td>\nLS (Low-power Schottky)<\/td>\n<\/tr>\n
\u062c\u0647\u062f \u0627\u0644\u0625\u0645\u062f\u0627\u062f<\/td>\n4.75V to 5.25V<\/td>\n<\/tr>\n
Inputs<\/td>\nA0-A3, B0-B3 (two 4-bit numbers)<\/td>\n<\/tr>\n
Outputs<\/td>\nA>B, A=B, A\n<\/tr>\n
Cascade Inputs<\/td>\nA>B, A=B, A\n<\/tr>\n
\u062a\u0623\u062e\u064a\u0631 \u0627\u0644\u0627\u0646\u062a\u0634\u0627\u0631<\/td>\n24ns typical (data to output)<\/td>\n<\/tr>\n
\u062f\u0631\u062c\u0629 \u062d\u0631\u0627\u0631\u0629 \u0627\u0644\u062a\u0634\u063a\u064a\u0644<\/td>\n0\u00b0C to +70\u00b0C<\/td>\n<\/tr>\n
\u0627\u0644\u062d\u0632\u0645\u0629<\/td>\nPDIP-16 (19.3 x 6.35mm)<\/td>\n<\/tr>\n<\/table>\n

\u0627\u0644\u0645\u064a\u0632\u0627\u062a<\/h2>\n
    \n
  • Compares two 4-bit binary or BCD numbers<\/li>\n
  • Three outputs: A>B, A=B, A\n
  • Cascading inputs for comparing 8, 12, 16+ bits<\/li>\n
  • Only one output HIGH at a time<\/li>\n<\/ul>\n

    \u0627\u0644\u062a\u0637\u0628\u064a\u0642\u0627\u062a<\/h2>\n
      \n
    • Address comparison<\/li>\n
    • Digital magnitude comparison<\/li>\n
    • Process control (temperature, pressure limits)<\/li>\n
    • Sorting and ranking logic<\/li>\n<\/ul>","protected":false},"excerpt":{"rendered":"

      Product Overview The SN74LS85N from Texas Instruments is a 4-bit magnitude comparator that determines whether one 4-bit binary number is greater than, less than, or equal to another, with cascading inputs for comparing numbers wider than 4 bits in a 16-pin PDIP package. Key Specifications Function 4-bit magnitude comparator Logic Family LS (Low-power Schottky) Supply […]<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[13,20],"tags":[],"chip_brand":[138],"class_list":["post-7974","post","type-post","status-publish","format-standard","hentry","category-integrated-circuits-ics","category-interface-ics","chip_brand-ti"],"acf":{"brief_explanation":"4-bit magnitude comparator, A>B\/A=B\/AB, A=B, or AB, A=B, AB=LOW (indicating that the lower-order bits are equal). For 8-bit comparison, the lower-order 7485's outputs connect to the higher-order 7485's cascade inputs. The comparison is performed from the most significant bit downward: if A3>B3, then A>B regardless of lower bits; if A3=B3, the comparison proceeds to A2 vs B2, and so on. If all four bits are equal, the result depends on the cascade inputs. The N suffix denotes the PDIP-16 through-hole package.","working_principle":"The SN74LS85N performs comparison starting from the MSB: if A3>B3 \u2192 A>B output HIGH; if A3B output reflects the cascade A>B input; AB=LOW, cascade A\n

Pin<\/th>Name<\/th>Type<\/th>Description<\/th><\/tr>\n
1<\/td>B3<\/td>Input<\/td>Input B bit 3 (MSB)<\/td><\/tr>\n
2<\/td>AInput<\/td>Cascade input: A less than B<\/td><\/tr>\n
3<\/td>A=B<\/td>Input<\/td>Cascade input: A equals B<\/td><\/tr>\n
4<\/td>A>B<\/td>Input<\/td>Cascade input: A greater than B<\/td><\/tr>\n
5<\/td>A>B<\/td>Output<\/td>Output: A greater than B (active HIGH)<\/td><\/tr>\n
6<\/td>A=B<\/td>Output<\/td>Output: A equals B (active HIGH)<\/td><\/tr>\n
7<\/td>AOutput<\/td>Output: A less than B (active HIGH)<\/td><\/tr>\n
8<\/td>GND<\/td>Power<\/td>Ground<\/td><\/tr>\n
9<\/td>B0<\/td>Input<\/td>Input B bit 0 (LSB)<\/td><\/tr>\n
10<\/td>A0<\/td>Input<\/td>Input A bit 0 (LSB)<\/td><\/tr>\n
11<\/td>B1<\/td>Input<\/td>Input B bit 1<\/td><\/tr>\n
12<\/td>A1<\/td>Input<\/td>Input A bit 1<\/td><\/tr>\n
13<\/td>A2<\/td>Input<\/td>Input A bit 2<\/td><\/tr>\n
14<\/td>B2<\/td>Input<\/td>Input B bit 2<\/td><\/tr>\n
15<\/td>A3<\/td>Input<\/td>Input A bit 3 (MSB)<\/td><\/tr>\n
16<\/td>VCC<\/td>Power<\/td>Supply (5V)<\/td><\/tr>\n<\/table>","application_scenarios":"
    \n
  • 4-Bit Compare:<\/strong> Two 4-bit counters \u2192 A[3:0] and B[3:0]; cascade inputs: A=B=HIGH, A>B=LOW, A\n
  • 8-Bit Compare:<\/strong> Lower 7485 compares bits 0-3; outputs \u2192 upper 7485 cascade inputs; upper compares bits 4-7; upper outputs give 8-bit result<\/li>\n
  • Alarm Threshold:<\/strong> ADC output \u2192 A[3:0]; threshold set by switches \u2192 B[3:0]; A>B output triggers alarm when reading exceeds threshold<\/li>\n
  • Sort:<\/strong> Compare two numbers; swap if A>B using multiplexers; building block for sorting networks<\/li>\n<\/ul>","alternative_models":"\n
    Model<\/th>Manufacturer<\/th>Key Difference<\/th>Package<\/th>Supply<\/th><\/tr>\n
    74LS85N<\/td>TI\/Nexperia<\/td>Original TTL version with 5V-only supply, typical propagation delay 10-15ns<\/td>DIP-16<\/td>5V TTL<\/td><\/tr>\n
    74LS85D<\/td>TI\/Nexperia<\/td>Surface-mount SOIC version of LS with identical logic function<\/td>SOIC-16<\/td>5V TTL<\/td><\/tr>\n
    74HC85D<\/td>TI\/Nexperia<\/td>CMOS version with wide 2-6V supply range, lower power consumption and higher noise immunity<\/td>SOIC-16<\/td>2-6V CMOS<\/td><\/tr>\n
    74HC85N<\/td>TI\/Nexperia<\/td>Through-hole DIP version of HC family for prototyping and repair<\/td>DIP-16<\/td>2-6V CMOS<\/td><\/tr>\n
    74HCT85D<\/td>TI\/Nexperia<\/td>CMOS with TTL-compatible input levels, ideal for mixing with LS devices at 5V<\/td>SOIC-16<\/td>4.5-5.5V TTL-in<\/td><\/tr>\n
    74HCT85N<\/td>TI\/Nexperia<\/td>Through-hole DIP version of HCT family for prototyping and repair<\/td>DIP-16<\/td>4.5-5.5V TTL-in<\/td><\/tr>\n<\/table>\n

    The 7485 is a 4-Bit Magnitude Comparator. Family variants span from the original LS TTL (5V only) to modern LVC\/AUP (down to 0.8V). HC and HCT versions offer 2-6V CMOS operation with HCT providing TTL-compatible input thresholds for mixed 5V systems. CD4000-series equivalents offer the widest 3-18V supply range at the cost of lower switching speed. DIP packages (N suffix) are through-hole; SOIC (D suffix) and TSSOP are surface-mount.<\/p>"},"_links":{"self":[{"href":"https:\/\/materialparts.com\/ar\/wp-json\/wp\/v2\/posts\/7974","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/materialparts.com\/ar\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/materialparts.com\/ar\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/materialparts.com\/ar\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/materialparts.com\/ar\/wp-json\/wp\/v2\/comments?post=7974"}],"version-history":[{"count":1,"href":"https:\/\/materialparts.com\/ar\/wp-json\/wp\/v2\/posts\/7974\/revisions"}],"predecessor-version":[{"id":8161,"href":"https:\/\/materialparts.com\/ar\/wp-json\/wp\/v2\/posts\/7974\/revisions\/8161"}],"wp:attachment":[{"href":"https:\/\/materialparts.com\/ar\/wp-json\/wp\/v2\/media?parent=7974"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/materialparts.com\/ar\/wp-json\/wp\/v2\/categories?post=7974"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/materialparts.com\/ar\/wp-json\/wp\/v2\/tags?post=7974"},{"taxonomy":"chip_brand","embeddable":true,"href":"https:\/\/materialparts.com\/ar\/wp-json\/wp\/v2\/chip_brand?post=7974"}],"curies":[{"name":"\u062f\u0628\u0644\u064a\u0648 \u0628\u064a","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}