The 1N4148 is very inexpensive and works well to cover a lot of low current applications. You are correct that they are quite common. I salvage a lot of circuit boards and it is rare for there not to be at least one and frequently 10 or 20 on a single circuit board. There is also several manufacturers who have made this device under the same part number. Occasionally there will be a slightly different first 2 characters in place of the 1N but the 4148 remains the same. Because of this the parts has been used in boards from all over the world. Even Wikipedia has an article about it.
The 1N4148 is very inexpensive and works well to cover a lot of low current applications. You are correct that they are quite common. I salvage a lot of circuit boards and it is rare for there not to be at least one and frequently 10 or 20 on a single circuit board. There is also several manufacturers who have made this device under the same part number. Occasionally there will be a slightly different first 2 characters in place of the 1N but the 4148 remains the same. Because of this the parts has been used in boards from all over the world. Even Wikipedia has an article about it.
