The industrial camera used by a machine vision supplier needs to interact with the main controller (such as industrial computer) control/feedback signal. The IO port level of the industrial camera is 5VTLL, and the IO port of the controller is DC24V, which causes the level mismatch. Later, we recommended that they use our DC amplifier board with input signal 3-5V and output DC12-24V, which perfectly solves the problem. In addition, the input/output end of our board adopts photoelectric isolation, which completely disconnects the industrial camera working with 5V power supply and the controller working with 24V power supply from electrical connection, further improving the safety and reliability of the system.