UC3843BD1013TR

UC3843BD1013TR is the STMicroelectronics UC3843B current-mode PWM controller in its SO-8 tape-and-reel ordering code; the maker’s eStore carries a page for this exact code and lists the UC3843BD1 device as Active in the SO-8 package on tape and reel. Inside ST’s coding the D1 denotes the SO-8 package and 013TR denotes the 13-inch reel. Verified figures, read on the ST UC384xB electrical table: a reference-voltage total output variation of 4.82 V to 5.18 V over line, load and temperature on the UC384XB column, oscillator frequency of 49 kHz minimum, 52 kHz typical and 55 kHz maximum at 25 °C with RT of 10 kΩ and CT of 3.3 nF (48 kHz to 56 kHz across the full temperature range), error-amplifier input of 2.42 V minimum, 2.50 V typical and 2.58 V maximum, and current-mode operation specified to 500 kHz. The selection point is the UC384x architecture itself: a complete fixed-frequency current-mode controller — trimmed oscillator, undervoltage-locked reference, error amplifier and a high-current totem-pole output — for off-line flyback and forward auxiliary supplies. Selection advice: within the B family the members differ in their undervoltage-lockout thresholds and maximum duty cycle, which decide whether a design self-starts from a high-voltage bus; check the family table for the exact code before treating a UC3842B or UC3844B offer as equivalent. Parameters verified against the ST UC384xB datasheet electrical tables and the ST eStore page for this code.