▁simple ▁R 1 / R 2 ▁voltage ▁division ▁calculation ▁less ▁accurate ▁for ▁higher ▁values ▁of ▁R . ▁ ▁See ▁also ▁▁ ▁DC ▁to ▁DC ▁converter ▁– ▁A ▁class ▁of ▁devices ▁which ▁convert ▁one ▁DC ▁voltage ▁level ▁to ▁another . ▁Linear ▁regul ators ▁( and ▁thus ▁ 7 8 xx ▁devices ) ▁are ▁a ▁form ▁of ▁DC ▁to ▁DC ▁converter . ▁ ▁List ▁of ▁linear ▁integrated ▁circ uits ▁ ▁List ▁of ▁L M - series ▁integrated ▁circ uits ▁ ▁L M 3 1 7 ▁– ▁A ▁similar ▁linear ▁reg ulator ▁chip ▁with ▁a ▁configur able ▁output ▁voltage . ▁ ▁References ▁ ▁External ▁links ▁▁ ▁Power ▁Supp ly ▁Design ▁Bas ics ▁- ▁S GS - Th om son ▁Micro elect ron ics ▁( now ▁ST ) ▁ ▁Re verse ▁engineering ▁a ▁ 7 8 0 5 ▁voltage ▁reg ulator , ▁detailed ▁information ▁about ▁how ▁a ▁ 7 8 0 5 ▁works ▁and ▁reference ▁links ▁▁ 7 8 0 0 ▁series ▁voltage ▁regul ators ▁- ▁description ▁& ▁circ uits . ▁ ▁Dat as he ets ▁ ▁Vol t age ▁Reg ulator ▁Dat ab ook ▁( H istor ical ▁ 1 9 8 0 ), ▁National ▁Sem icon duct or ▁ ▁L M 7 8 xx ▁/ ▁L M 3 4 0 ▁( pos itive ), ▁Texas ▁Inst ru ments ▁( TI ▁acquired ▁National ▁Sem icon duct or ) ▁ ▁L 7 8 xx ▁( pos itive ), ▁ST M icro elect ron ics ▁ ▁L M 7 9 xx ▁( negative ), ▁Texas ▁Inst ru ments