i think when a dc-dc convert works at discontinue mode , the switch state is on-> off -> another off ->on ->off ..... but i use the ltspice it tell me lt1316's worke state is on->off->on-
off(servel this state)->a long time off->on->off->....
(i am sorry i can not post my picture on the group )
formatting link
So the question is how to measure the Duty cycle?