{"id":6600,"date":"2026-06-18T15:31:26","date_gmt":"2026-06-18T15:31:26","guid":{"rendered":"https:\/\/materialparts.com\/uc3842bn\/"},"modified":"2026-06-18T15:31:26","modified_gmt":"2026-06-18T15:31:26","slug":"uc3842bn","status":"publish","type":"post","link":"https:\/\/materialparts.com\/es\/uc3842bn\/","title":{"rendered":"UC3842BN"},"content":{"rendered":"

Productos<\/h2>\n

The UC3842BN from Texas Instruments is a current-mode PWM controller for offline and DC-DC switching power supplies. With fixed-frequency operation up to 500kHz, 1A totem-pole output, and UVLO with 16V\/10V hysteresis, it is the most widely used SMPS controller IC. Packaged in 8-PDIP.<\/p>\n

Especificaciones<\/h2>\n\n\n\n\n\n\n\n\n\n\n\n
Control Mode<\/td>\nCurrent-mode PWM<\/td>\n<\/tr>\n
Switching Frequency<\/td>\nUp to 500kHz<\/td>\n<\/tr>\n
Start Current<\/td>\n0.5mA (typ)<\/td>\n<\/tr>\n
Operating Current<\/td>\n11mA (typ)<\/td>\n<\/tr>\n
UVLO Threshold<\/td>\n16V ON \/ 10V OFF<\/td>\n<\/tr>\n
Reference Voltage<\/td>\n5V +\/-2%<\/td>\n<\/tr>\n
Output Drive<\/td>\n+\/-1A peak totem-pole<\/td>\n<\/tr>\n
Max Duty Cycle<\/td>\n96%<\/td>\n<\/tr>\n
Paquete<\/td>\n8-PDIP<\/td>\n<\/tr>\n
Temperatura de funcionamiento<\/td>\n0 to +70 C<\/td>\n<\/tr>\n<\/table>\n

Caracter\u00edsticas<\/h2>\n
    \n
  • Current-mode control for improved line regulation<\/li>\n
  • Low start-up current: 0.5mA typical<\/li>\n
  • UVLO with 6V hysteresis for reliable startup<\/li>\n
  • +\/-1A totem-pole output for direct MOSFET drive<\/li>\n
  • 5V precision reference (2%)<\/li>\n
  • Automatic feedforward compensation<\/li>\n
  • Pulse-by-pulse current limiting<\/li>\n<\/ul>\n

    Aplicaciones<\/h2>\n
      \n
    • Offline flyback converters<\/li>\n
    • Forward and boost converters<\/li>\n
    • DC-DC switching regulators<\/li>\n
    • Battery chargers<\/li>\n<\/ul>","protected":false},"excerpt":{"rendered":"

      Product Overview The UC3842BN from Texas Instruments is a current-mode PWM controller for offline and DC-DC switching power supplies. With fixed-frequency operation up to 500kHz, 1A totem-pole output, and UVLO with 16V\/10V hysteresis, it is the most widely used SMPS controller IC. Packaged in 8-PDIP. Key Specifications Control Mode Current-mode PWM Switching Frequency Up to […]<\/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":[13,29],"tags":[],"chip_brand":[138],"class_list":["post-6600","post","type-post","status-publish","format-standard","hentry","category-integrated-circuits-ics","category-power-management-ics-pmic","chip_brand-ti"],"acf":{"brief_explanation":"Current-mode PWM controller, 500kHz, 1A output, 16V\/10V UVLO, 8-PDIP","date_code":"","package_case":"8-PDIP","in_stock":3791,"datasheet":"https:\/\/www.ti.com\/lit\/ds\/symlink\/uc3842.pdf","price":"$0.55 @ 1ku","product_introduction":"The UC3842BN from Texas Instruments is the industry-standard current-mode PWM controller for switching power supplies. It uses peak current-mode control, where the output switch is turned on at the start of each clock cycle and turned off when the peak inductor current reaches the threshold set by the error amplifier. This provides inherent line voltage feedforward compensation and pulse-by-pulse current limiting. The 1A totem-pole output directly drives power MOSFET gates without external driver circuits. The 16V\/10V UVLO with 6V hysteresis ensures reliable startup from high-voltage bus through a start-up resistor. The 5V +\/-2% reference powers the error amplifier and external circuits. The UC3842 is the B-version (higher accuracy) in 8-PDIP for 0-70C operation.","working_principle":"The UC3842 uses peak current-mode control: an internal oscillator sets the switching frequency via RT\/CT, and generates a clock pulse that sets the PWM latch, turning on the output driver. Current through the external MOSFET is sensed via a resistor on the ISENSE pin. When the voltage on ISENSE exceeds the error amplifier output (divided by 3), the comparator resets the PWM latch, turning off the output. The error amplifier compares a fraction of the output voltage (via the VFB pin) to the 5V reference and adjusts the current threshold accordingly. Current-mode control inherently rejects input voltage variations (feedforward) because the peak current setpoint automatically compensates for changes in input voltage. The slope compensation (typically a small ramp added to the current sense signal) prevents sub-harmonic oscillation at duty cycles above 50%.","pin_description":"
      Pin<\/th>Name<\/th>Function<\/th><\/tr>
      1<\/td>COMP<\/td>Error amplifier output \/ compensation<\/td><\/tr>
      2<\/td>VFB<\/td>Voltage feedback input (error amp inverting)<\/td><\/tr>
      3<\/td>ISENSE<\/td>Current sense input (compare threshold = VCOMP\/3)<\/td><\/tr>
      4<\/td>RT\/CT<\/td>Oscillator timing resistor and capacitor<\/td><\/tr>
      5<\/td>GND<\/td>Ground<\/td><\/tr>
      6<\/td>OUTPUT<\/td>PWM output (totem-pole, +\/-1A)<\/td><\/tr>
      7<\/td>VCC<\/td>Supply voltage (UVLO 16V\/10V)<\/td><\/tr>
      8<\/td>VREF<\/td>5V reference output (2%)<\/td><\/tr><\/table>","application_scenarios":"
      • Offline flyback converter primary-side controller with 16V UVLO startup<\/li>
      • DC-DC forward and boost converters with 500kHz switching frequency<\/li>
      • Battery charger SMPS with pulse-by-pulse current limiting<\/li>
      • Multiple output power supplies using current-mode control for cross-regulation<\/li><\/ul>","alternative_models":"
        Model<\/th>Manufacturer<\/th>Key Difference<\/th><\/tr>
        UC3843BN<\/td>TI<\/td>8.5V\/7.9V UVLO, lower startup voltage<\/td><\/tr>
        UC3844BN<\/td>TI<\/td>50% max duty cycle, forward converter<\/td><\/tr>
        UC3845BN<\/td>TI<\/td>50% duty, 8.5V\/7.9V UVLO<\/td><\/tr>
        LM5022<\/td>TI<\/td>60V, current mode, active clamp<\/td><\/tr><\/table>"},"_links":{"self":[{"href":"https:\/\/materialparts.com\/es\/wp-json\/wp\/v2\/posts\/6600","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/materialparts.com\/es\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/materialparts.com\/es\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/materialparts.com\/es\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/materialparts.com\/es\/wp-json\/wp\/v2\/comments?post=6600"}],"version-history":[{"count":0,"href":"https:\/\/materialparts.com\/es\/wp-json\/wp\/v2\/posts\/6600\/revisions"}],"wp:attachment":[{"href":"https:\/\/materialparts.com\/es\/wp-json\/wp\/v2\/media?parent=6600"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/materialparts.com\/es\/wp-json\/wp\/v2\/categories?post=6600"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/materialparts.com\/es\/wp-json\/wp\/v2\/tags?post=6600"},{"taxonomy":"chip_brand","embeddable":true,"href":"https:\/\/materialparts.com\/es\/wp-json\/wp\/v2\/chip_brand?post=6600"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}