LMR33630ADDAR

LMR33630ADDAR is the tape-and-reel HSOIC-8 (DDA) ordering code for the Texas Instruments LMR33630 synchronous step-down converter, listed as Active. The letter A in this code is a switching-frequency grade and nothing else: on this family A fixes 400 kHz (340 kHz minimum, 400 kHz typical, 460 kHz maximum), B fixes 1.4 MHz and C fixes 2.1 MHz, while the adjustable 1 V to 24 V output range is common to every grade. Read on the A rows: feedback voltage of 0.985 V minimum, 1.0 V typical and 1.015 V maximum, quiescent current of 24 µA typical and 34 µA maximum, and a high-side current limit of 3.85 A minimum, 4.5 A typical and 5.05 A maximum, from an input of 3.8 V to 36 V delivering 3 A. The selection point is the low-frequency grade itself: 400 kHz keeps switching loss and EMI filtering manageable on 24 V industrial and automotive auxiliary rails, where the faster grade’s smaller inductor is not worth its noise and efficiency cost. Selection advice: the frequency is fixed by the order code, not by a pin strap - swapping to the B or C code on the same footprint changes the EMI and inductor design, so lock the A code in the BOM. Parameters verified against the TI LMR33630 datasheet (frequency-grade table and electrical characteristics) and the TI product page.