To cut out an object in Photoshop, open the picture from which you will cut the object, then you need to select the Quick Mask mode editing in the Quick mask is a rectangular button with a circle at the bottom of the toolbar).
Then you choose the Brush tool, pick a brush with soft edges, it is still called a soft brush, where you choose any size ranging from 3 px to 10 px.
Then you maximize your image, it is necessary to when you drew it, it was done very carefully. In order to enlarge the picture, you need to select the Zoom tool. Tracing the outline of the shape of the selected brush. Make sure that the main color was black and the mask mode is a selection!
After this you pick the Paint bucket tool, it fills, and accordingly, you fill in the contour you have selected.
Then you exit the Quick Mask mode and you see the highlighted area.
After that press Ctrl+J the selection to be copied to a new layer.
So you get a new layer, on top of which is the desired object. In this case, note that you have an outline of the object is smooth, so if you move this object on any other background it will not look cut.
Thus, you can cut an object in Photoshop. As you can see, it's pretty simple. The only difficulty you might have when you trace the circuit, but there is the possibility of increasing of the object. If even after you increase the object, you still something does not work, do not despair. Try again.
Such selection it is better to start with large objects. It is not necessary to go directly to the small details in the photos. Let your hand get used to it, and only after you will be able to outline the major details, you can go to smaller.