How to properly use ngModel in your directives?

Question

Angular

Hello.
I made a directive, it is called something like this , it declares a scope { ngModel: '=' } in the controller of the directive I assign values ​​to $ scope.ngModel , but they do not come immediately, but about once every 2-3 seconds. How to properly use ngModel in your directives?
<mydirective ng-model="value"></mydirective>

Answer 1

so I just assign $scope.ngModel and call $scope.$apply()