LM2574 LM239/339/2901 LM2574 Switch mode power supply regulator Pin (1) + Feedback from regulated output (2) 0 V ground (3) e-_ Output control, on = low, off = high (4) 0 V ground ) ____ 5 V0 to 40 V supply (6) N/e (7) __ Regulated output (8) Nic Notes: A preset or fixed resistor network is connected between the output and pin1 for the adjustable regulator type. Pins 6 and 8 are usually connected to the printed circuit land for heat dissipation Pin 7 output depends on version. LM2574-3.3 (8V3), LM2574-5 (65V0), LM2574-12 (12 V), LM2574-15(15V0) and LM2574-adj (1V23 to 37 V LM239 LM339 LM2901 fo" Quad comparators 4 Pin C1 a (1) > Comparator 2 output dq, (2) __> Comparator 1 output Le (3) __ Split supply = +18 V. Single supply = +386 V (4) + Inverted input comparator 1 (5) _ Non-inverted input comparator 1 (6) T__ Inverted input comparator 2 (7) +__ Non --inverted input comparator 2 (8) cM _ Inverted input comparator 3 (9) <-___ Non-inverted input comparator 3 (10) +_____ [nverted input comparator 4 (11) M\_- _ Non- inverted input comparator 4 (12) +\__ Split supply = ~18 V, single supply = 0 V ground (13) Comparator 4 output (14) p Comparator 3 output Notes: The numbers given to the individual comparators serve only to distinguish them from each other.