cupoftea
Advanced Member level 5
Hi,
We are doing an offline flyback. We obviously want to pick a controller which has output overload hiccup mode protection since doing this with discrete components
means a high component count. However, we are finding that virtually every offline controller that has inbuilt overload protection via hiccuping, also has
some latching protections.
For example, all the the NCP1239X controllers will latch off if the current sense pin sees more than 1.2V. And all the NCP1219B controllers will latch off if the bias coil goes overvoltage.
But we dont want any latching functionality...since a mains transient or other such noisy electrical malaise may somehow get noise into the controller and trip the latch spuriously.
Do you believe it is possible for a latch to trip spuriously in this way?.....ie, the latch trips even though the conditions required to trip the latch havent been experienced. (ie it trips due to ambient noise)
We are doing an offline flyback. We obviously want to pick a controller which has output overload hiccup mode protection since doing this with discrete components
means a high component count. However, we are finding that virtually every offline controller that has inbuilt overload protection via hiccuping, also has
some latching protections.
For example, all the the NCP1239X controllers will latch off if the current sense pin sees more than 1.2V. And all the NCP1219B controllers will latch off if the bias coil goes overvoltage.
But we dont want any latching functionality...since a mains transient or other such noisy electrical malaise may somehow get noise into the controller and trip the latch spuriously.
Do you believe it is possible for a latch to trip spuriously in this way?.....ie, the latch trips even though the conditions required to trip the latch havent been experienced. (ie it trips due to ambient noise)
