{"product_id":"uc3843-dip8-current-mode-pwm-controller-ic-50-duty-cycle","title":"UC3843 DIP-8 Current-Mode PWM Controller IC 50% Duty Cycle (5-Pack)","description":"\u003ch2\u003eUC3843 DIP-8 Current-Mode PWM Controller IC - 50% Max Duty Cycle (5-Pack)\u003c\/h2\u003e\u003cp\u003eThe \u003cstrong\u003eUC3843\u003c\/strong\u003e is a current-mode PWM controller in a \u003cstrong\u003eDIP-8\u003c\/strong\u003e through-hole package, featuring a \u003cstrong\u003e50% maximum duty cycle clamp\u003c\/strong\u003e and low UVLO thresholds (\u003cstrong\u003e8.5V on \/ 7.6V off\u003c\/strong\u003e). The through-hole DIP-8 package makes it ideal for prototyping, repair work, and breadboard-based SMPS development. Functionally identical to the UC3845 (SOP-8 SMD version).\u003c\/p\u003e\u003ch3\u003eKey Specifications\u003c\/h3\u003e\u003ctable\u003e\n\u003ctr\u003e\n\u003cth\u003eParameter\u003c\/th\u003e\n\u003cth\u003eValue\u003c\/th\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePart Number\u003c\/td\u003e\n\u003ctd\u003eUC3843\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePackage\u003c\/td\u003e\n\u003ctd\u003eDIP-8 (through-hole)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTopology\u003c\/td\u003e\n\u003ctd\u003eCurrent-mode PWM (fixed frequency)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMax Duty Cycle\u003c\/td\u003e\n\u003ctd\u003e50% (internal clamp)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMax Oscillator Frequency\u003c\/td\u003e\n\u003ctd\u003e500kHz\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eGate Drive Output\u003c\/td\u003e\n\u003ctd\u003e1A peak (totem-pole)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eUVLO Thresholds\u003c\/td\u003e\n\u003ctd\u003e8.5V on \/ 7.6V off\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eReference Voltage\u003c\/td\u003e\n\u003ctd\u003e5V (2% accuracy)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCurrent Sense Threshold\u003c\/td\u003e\n\u003ctd\u003e1V (cycle-by-cycle OCP)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOperating Temperature\u003c\/td\u003e\n\u003ctd\u003e0C to +70C\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eQuantity\u003c\/td\u003e\n\u003ctd\u003e5 pieces\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/table\u003e\u003ch3\u003eUC3843 Pin Configuration (DIP-8)\u003c\/h3\u003e\u003ctable\u003e\n\u003ctr\u003e\n\u003cth\u003ePin\u003c\/th\u003e\n\u003cth\u003eName\u003c\/th\u003e\n\u003cth\u003eFunction\u003c\/th\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e1\u003c\/td\u003e\n\u003ctd\u003eCOMP\u003c\/td\u003e\n\u003ctd\u003eError amplifier output \/ compensation\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e2\u003c\/td\u003e\n\u003ctd\u003eVFB\u003c\/td\u003e\n\u003ctd\u003eVoltage feedback input\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e3\u003c\/td\u003e\n\u003ctd\u003eISENSE\u003c\/td\u003e\n\u003ctd\u003eCurrent sense input (1V threshold)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e4\u003c\/td\u003e\n\u003ctd\u003eRT\/CT\u003c\/td\u003e\n\u003ctd\u003eOscillator timing resistor\/capacitor\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e5\u003c\/td\u003e\n\u003ctd\u003eGND\u003c\/td\u003e\n\u003ctd\u003eGround\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e6\u003c\/td\u003e\n\u003ctd\u003eOUTPUT\u003c\/td\u003e\n\u003ctd\u003eGate drive output (1A totem-pole)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e7\u003c\/td\u003e\n\u003ctd\u003eVCC\u003c\/td\u003e\n\u003ctd\u003eSupply voltage (8.5V-30V)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e8\u003c\/td\u003e\n\u003ctd\u003eVREF\u003c\/td\u003e\n\u003ctd\u003e5V reference output\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/table\u003e\u003ch3\u003eWhy Choose UC3843?\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eDIP-8 Through-Hole\u003c\/strong\u003e - Breadboard-friendly for prototyping and repair\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e50% Duty Cycle Clamp\u003c\/strong\u003e - Safe for forward converter transformer volt-second balance\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eLow UVLO\u003c\/strong\u003e - 8.5V startup suits lower-voltage auxiliary supplies\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e1A Gate Drive\u003c\/strong\u003e - Directly drives MOSFETs up to ~10nC gate charge\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eIndustry Standard\u003c\/strong\u003e - Widely used in SMPS repair; extensive reference designs\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eTypical Applications\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003eSingle-ended forward converter SMPS\u003c\/li\u003e\n\u003cli\u003eFlyback converter with lower UVLO requirement\u003c\/li\u003e\n\u003cli\u003eDC-DC converter prototyping on breadboard\u003c\/li\u003e\n\u003cli\u003eSMPS repair replacement (monitors, adapters, industrial PSU)\u003c\/li\u003e\n\u003cli\u003eBoost converter controller\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eFAQ\u003c\/h3\u003e\u003cp\u003e\u003cstrong\u003eQ: How do I set the oscillator frequency for UC3843?\u003c\/strong\u003e Frequency = 1.72 \/ (RT x CT). For 65kHz: RT = 10k ohm, CT = 2.7nF. For 100kHz: RT = 10k ohm, CT = 1.8nF.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eQ: Can UC3843 replace UC3842 in an existing design?\u003c\/strong\u003e Only if the design operates below 50% duty cycle. UC3843 will clamp duty cycle at 50%; UC3842 allows up to 100%. Check the original design's maximum duty cycle before substituting.\u003c\/p\u003e\u003ch3\u003ePackage Contents\u003c\/h3\u003e\u003cul\u003e\u003cli\u003e5x UC3843 DIP-8 Current-Mode PWM Controller IC\u003c\/li\u003e\u003c\/ul\u003e","brand":"Keszoox","offers":[{"title":"Default Title","offer_id":46991506505963,"sku":"\u003cnone\u003e","price":5.52,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0677\/1005\/8731\/files\/uc3843-dip8-pwm-controller-ic-chipset.webp?v=1761529869","url":"https:\/\/keszoox.com\/products\/uc3843-dip8-current-mode-pwm-controller-ic-50-duty-cycle","provider":"Keszoox","version":"1.0","type":"link"}