Type & no Sb/Br) UC3842NG4 ACTIVE PDIP P 8 50 Green (RoHS CU NIPDAU N / A for Pkg Type & no Sb/Br) UC3843D ACTIVE SOIC D 14 50 Green (RoHS CU NIPDAU Level-1-260C-UNLIM & no Sb/Br) UC3843D8 ACTIVE SOIC D 8 75 Green (RoHS CU NIPDAU Level-1-260C-UNLIM & no Sb/Br) UC3843D8G4 ACTIVE SOIC D 8 75 Green (RoHS
off-line applications The corresponding necessary features to implement off-line or thresholdsfor the UC3843 and UC3845 are 8.5 V witha minimalexternalpartscount.Internallyimto duty cycles approaching 100%. A range of the mentedcircuitsincludeundervoltagelockoutfeatzero to < 50 % is obtained by the UC3844
Widerstand von 0,1 Ohm ersetzt, dann kann man ja 3 Ampere Last eine Spannung > 1 V am Pin 3 von UC3843 messen. Der Wert ist dann auch mit dem vorgesehenen Poti einstellbar. Jetzt kommt der lustige Punkt: Trotz der ausreichend hohen spannung am Pin3 setzt die Strombegrenzung nicht ein! Wenn man in das Datasheet des UC3843 ein sieht, dass der --- Peakstrom --- eines "irgendwie periodischen Stroms" muss und dafür eventuell auch ein RC -Filter eingeführt werden muss (ich auf der Platine erkennbar!). Ich vermute, dass der
suitedoff-lineapplicationsThecorrespondingthresh- a minimal external parts count. Internally imple- oldsfortheUC3843BandUC3845Bare8.5Vand7.9 mented circuits include a trimmed oscillator for pre- V. The UC3842B and UC3843B can operate toduty cise DUTY CYCLE CONTROL under voltage lock- cycles approaching 100%. A range
suitedoff-lineapplicationsThecorrespondingthresh- a minimal external parts count. Internally imple- oldsfortheUC3843BandUC3845Bare8.5Vand7.9 mented circuits include a trimmed oscillator for pre- V. The UC3842B and UC3843B can operate toduty cise DUTY CYCLE CONTROL under voltage lock- cycles approaching 100%. A range
6562D L6562D (pfc_ctrl) Q1 60R125CP D3 5L05 Q9 N80C3 Q4 N80C3 IC2 1203D NCP1203D (pwm_ctrl) IC3 UC3843AD D1 BZT03C Q12 BC848 Q13 BC858 R29 47ohms D4 FR107 We recommend all kits are fitted by qualified engineers We accept no responsibility for loss, injury or damage caused by your use of this kit as
for both CMC and current peak-current limit. The feedforward resistor (R ) ff limiting (similar to UC3843). The RC filter shown provides multiple advantages for constant power eliminates nuisance noise from the current- limit and better line rejection. feedback signal. One typical noise source is the Fig
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