{"id":7924,"date":"2026-06-28T04:28:51","date_gmt":"2026-06-28T04:28:51","guid":{"rendered":"https:\/\/materialparts.com\/sn74ls47n\/"},"modified":"2026-06-28T11:45:59","modified_gmt":"2026-06-28T11:45:59","slug":"sn74ls47n","status":"publish","type":"post","link":"https:\/\/materialparts.com\/ar\/sn74ls47n\/","title":{"rendered":"SN74LS47N"},"content":{"rendered":"

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

The SN74LS47N from Texas Instruments is a BCD-to-7-segment decoder\/driver with active-low (current-sinking) outputs for driving common-anode LED displays directly, including ripple-blanking and lamp-test functions 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\n\n\n\n
\u0627\u0644\u0648\u0638\u064a\u0641\u0629<\/td>\nBCD-to-7-segment decoder\/driver<\/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 (5V nominal)<\/td>\n<\/tr>\n
\u0646\u0648\u0639 \u0627\u0644\u0625\u062e\u0631\u0627\u062c<\/td>\nActive-low (current sink, open-collector)<\/td>\n<\/tr>\n
Output Sink Current<\/td>\n24mA max per segment<\/td>\n<\/tr>\n
\u062a\u0623\u062e\u064a\u0631 \u0627\u0644\u0627\u0646\u062a\u0634\u0627\u0631<\/td>\n100ns typical<\/td>\n<\/tr>\n
Input (BCD)<\/td>\n4-bit binary-coded decimal (A, B, C, D)<\/td>\n<\/tr>\n
Ripple Blanking Input (RBI)<\/td>\nBlanks leading zeros when LOW<\/td>\n<\/tr>\n
Ripple Blanking Output (RBO)<\/td>\nGoes LOW when RBI=LOW and BCD=0<\/td>\n<\/tr>\n
Lamp Test (LT)<\/td>\nActive-low; lights all segments when LOW<\/td>\n<\/tr>\n
Display Type<\/td>\nCommon-anode LED displays<\/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
  • BCD-to-7-segment decoding for digits 0-9<\/li>\n
  • Active-low outputs for common-anode displays<\/li>\n
  • Direct LED drive: 24mA per segment<\/li>\n
  • Ripple blanking for leading\/trailing zero suppression<\/li>\n
  • Lamp test function (all segments ON)<\/li>\n
  • Blanking on invalid BCD codes (10-15)<\/li>\n<\/ul>\n

    \u0627\u0644\u062a\u0637\u0628\u064a\u0642\u0627\u062a<\/h2>\n
      \n
    • 7-segment LED display driving<\/li>\n
    • Digital counter\/meter displays<\/li>\n
    • Clock and timer displays<\/li>\n
    • Instrumentation readout<\/li>\n
    • Multi-digit display with zero suppression<\/li>\n<\/ul>","protected":false},"excerpt":{"rendered":"

      Product Overview The SN74LS47N from Texas Instruments is a BCD-to-7-segment decoder\/driver with active-low (current-sinking) outputs for driving common-anode LED displays directly, including ripple-blanking and lamp-test functions in a 16-pin PDIP package. Key Specifications Function BCD-to-7-segment decoder\/driver Logic Family LS (Low-power Schottky) Supply Voltage 4.75V to 5.25V (5V nominal) Output Type Active-low (current sink, open-collector) Output […]<\/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-7924","post","type-post","status-publish","format-standard","hentry","category-integrated-circuits-ics","category-interface-ics","chip_brand-ti"],"acf":{"brief_explanation":"BCD-to-7seg decoder, active-low, common-anode LED, RBI\/RBO, LT, PDIP-16","date_code":"","package_case":"PDIP-16 (19.3 x 6.35 x 4.57mm, 2.54mm pitch, through-hole)","in_stock":3800,"datasheet":"https:\/\/www.ti.com\/lit\/ds\/symlink\/sn74ls47.pdf","price":"$0.55 @ 1ku","product_introduction":"The SN74LS47N from Texas Instruments is a BCD-to-7-segment decoder\/driver designed to drive common-anode LED displays directly. The 4-bit BCD input (A, B, C, D) is decoded into the seven segment outputs (a through g) that drive the display. The active-low (current-sinking) outputs connect to the LED segments through current-limiting resistors; the common anode of the display connects to VCC. The 24mA per-segment sink capability can drive most standard LED displays at full brightness. The ripple-blanking feature suppresses leading or trailing zeros in multi-digit displays: the RBI (ripple-blanking input) of the most significant digit is grounded, and if that digit is 0, all segments are blanked and RBO (ripple-blanking output) goes LOW, which cascades to the next digit's RBI. The lamp-test (LT) input, when pulled LOW, turns on all seven segments regardless of the BCD input, useful for verifying display function. Invalid BCD codes (10-15) produce blanked or special patterns. The N suffix denotes the PDIP-16 through-hole package.","working_principle":"The SN74LS47N takes a 4-bit BCD input (D=MSB, A=LSB) and decodes it to activate the appropriate combination of the seven segment outputs (a-g) to display digits 0-9. The outputs are active-low open-collector NPN transistors: when a segment should be lit, the corresponding output transistor turns ON, sinking current from the LED through a current-limiting resistor to ground. For a common-anode display, the LED anodes are connected to VCC, and the cathodes connect to the 74LS47 outputs through resistors. The resistor value sets the LED current: R = (VCC - VLED - VOL) \/ ILED \u2248 (5V - 1.7V - 0.3V) \/ 10mA = 300\u03a9. The ripple-blanking logic works as follows: when RBI is LOW and the BCD input is 0000 (digit 0), all segment outputs are turned off (blanked) and RBO goes LOW. This RBO is connected to the RBI of the next-lower digit, cascading the blanking. The most significant digit has its RBI grounded, so if it displays 0, it is blanked and the blanking ripples down. The lamp-test (LT) input overrides all other inputs; when LT is LOW, all segment outputs are ON, illuminating all segments.","pin_description":"\n
      Pin<\/th>Name<\/th>Type<\/th>Description<\/th><\/tr>\n
      1<\/td>B<\/td>Input<\/td>BCD input B (bit 1)<\/td><\/tr>\n
      2<\/td>C<\/td>Input<\/td>BCD input C (bit 2)<\/td><\/tr>\n
      3<\/td>Lamp Test (LT)<\/td>Input<\/td>Lamp test (active LOW, all segments ON)<\/td><\/tr>\n
      4<\/td>RBI<\/td>Input<\/td>Ripple-blanking input (active LOW)<\/td><\/tr>\n
      5<\/td>RBO<\/td>Output<\/td>Ripple-blanking output (active LOW, cascade to next RBI)<\/td><\/tr>\n
      6<\/td>D<\/td>Input<\/td>BCD input D (MSB, bit 3)<\/td><\/tr>\n
      7<\/td>A<\/td>Input<\/td>BCD input A (LSB, bit 0)<\/td><\/tr>\n
      8<\/td>GND<\/td>Power<\/td>Ground<\/td><\/tr>\n
      9-15<\/td>e,d,c,b,a,g,f<\/td>Output<\/td>7-segment outputs (active LOW, open-collector)<\/td><\/tr>\n
      16<\/td>VCC<\/td>Power<\/td>Supply (4.75V to 5.25V)<\/td><\/tr>\n<\/table>","application_scenarios":"
        \n
      • 4-Digit Counter:<\/strong> 4\u00d7 74LS47 + 4\u00d7 common-anode displays; counter IC feeds BCD; RBI\/RBO cascades zero suppression<\/li>\n
      • Clock Display:<\/strong> Hours:minutes; leading zero blanked on tens-of-hours; LT button for display test<\/li>\n
      • DVM Readout:<\/strong> A\/D converter BCD output \u2192 74LS47 \u2192 display; RBI on MSB blanks leading zeros<\/li>\n
      • Temperature Display:<\/strong> MCU outputs BCD on 4 GPIO pins per digit; 74LS47 decodes to 7-segment<\/li>\n
      • Single Digit:<\/strong> One 74LS47 drives one common-anode display; 300\u03a9 resistors set 10mA per segment<\/li>\n<\/ul>","alternative_models":"\n
        Model<\/th>Manufacturer<\/th>Key Difference<\/th>Package<\/th>Supply<\/th><\/tr>\n
        74LS47N<\/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
        74LS47D<\/td>TI\/Nexperia<\/td>Surface-mount SOIC version of LS with identical logic function<\/td>SOIC-16<\/td>5V TTL<\/td><\/tr>\n
        74HC47D<\/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
        74HC47N<\/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
        74HCT47D<\/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
        74HCT47N<\/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 7447 is a BCD-to-7-Segment Decoder\/Driver. 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\/7924","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=7924"}],"version-history":[{"count":1,"href":"https:\/\/materialparts.com\/ar\/wp-json\/wp\/v2\/posts\/7924\/revisions"}],"predecessor-version":[{"id":8190,"href":"https:\/\/materialparts.com\/ar\/wp-json\/wp\/v2\/posts\/7924\/revisions\/8190"}],"wp:attachment":[{"href":"https:\/\/materialparts.com\/ar\/wp-json\/wp\/v2\/media?parent=7924"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/materialparts.com\/ar\/wp-json\/wp\/v2\/categories?post=7924"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/materialparts.com\/ar\/wp-json\/wp\/v2\/tags?post=7924"},{"taxonomy":"chip_brand","embeddable":true,"href":"https:\/\/materialparts.com\/ar\/wp-json\/wp\/v2\/chip_brand?post=7924"}],"curies":[{"name":"\u062f\u0628\u0644\u064a\u0648 \u0628\u064a","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}