▁be ▁the ▁same , ▁and ▁the ▁voltage ▁at ▁the ▁terminal s ▁of ▁the ▁di ode ▁must ▁be ▁the ▁same , ▁ ▁the ▁operating ▁point ▁of ▁the ▁circuit ▁will ▁be ▁at ▁the ▁intersection ▁of ▁the ▁curve ▁with ▁the ▁load ▁line . ▁ ▁In ▁a ▁B J T ▁circuit , ▁the ▁B J T ▁has ▁a ▁different ▁current - vol t age ▁( IC - V CE ) ▁characteristic ▁depending ▁on ▁the ▁base ▁current . ▁Pla cing ▁a ▁series ▁of ▁these ▁curves ▁on ▁the ▁graph ▁shows ▁how ▁the ▁base ▁current ▁will ▁affect ▁the ▁operating ▁point ▁of ▁the ▁circuit . ▁ ▁DC ▁and ▁AC ▁load ▁lines ▁Sem icon duct or ▁circ uits ▁typically ▁have ▁both ▁DC ▁and ▁AC ▁curr ents ▁in ▁them , ▁with ▁a ▁source ▁of ▁DC ▁current ▁to ▁bias ▁the ▁non linear ▁sem icon duct or ▁to ▁the ▁correct ▁operating ▁point , ▁and ▁the ▁AC ▁signal ▁super im posed ▁on ▁the ▁DC . ▁ ▁Load ▁lines ▁can ▁be ▁used ▁separately ▁for ▁both ▁DC ▁and ▁AC ▁analysis . ▁ ▁The ▁DC ▁load ▁line ▁is ▁the ▁load ▁line ▁of ▁the ▁DC ▁equivalent ▁circuit , ▁ ▁defined ▁by ▁reducing ▁the ▁re active ▁components ▁to ▁zero ▁( rep la cing ▁capac itors ▁by ▁open ▁circ uits ▁and ▁induct ors ▁by ▁short ▁circ uits ). ▁ ▁It ▁is ▁used ▁to ▁determine ▁the ▁correct ▁DC ▁operating ▁point , ▁often ▁called ▁the ▁ ▁Q ▁point . ▁ ▁Once ▁a ▁DC ▁operating ▁point ▁is ▁defined ▁by ▁the ▁DC ▁load ▁line , ▁an ▁AC ▁load ▁line ▁can ▁be ▁drawn ▁through ▁the ▁Q ▁point