Switching power supply is a type of power supply that uses modern power electronics technology to control the time ratio of the on and off of the switching transistor, maintaining a stable output voltage. Switching power supply is generally composed of pulse width modulation (PWM) control IC and MOSFET. With the development and innovation of power electronics technology, switch mode power supply technology is also constantly innovating. At present, switch mode power supplies are widely used in almost all electronic devices due to their small size, lightweight, and high efficiency, and are an indispensable power supply method for the rapid development of the electronic information industry today.

Our switch power supply brands include Phoenix Contact, DEUTRONIC D/C power supply, etc. Switching power supply products are widely used in industrial automation control, military equipment, scientific research equipment, LED lighting, industrial control equipment, communication equipment, power equipment, instruments and meters, medical equipment, semiconductor refrigeration and heating, air purifiers, electronic refrigerators, LCD displays, LED lights, communication equipment, audio-visual products, security monitoring, LED light bags, computer cases, digital products and instruments.
Let's witness the application of power switches in medical sensors together. The following is a partial circuit diagram of a switching power supply in medical equipment. (For reference only)

With the continuous development of modern medical equipment, especially electronic instruments directly connected to the human body, in addition to the requirements for their own performance, the consideration of human safety is also becoming increasingly important. For example, instruments that come into close contact with the human body, such as life monitors, mother and baby monitors, and baby insulation devices, mean that patients cannot cause electric shock or other hazards to the human body when using instruments. At present, there are many DC/DC module power supplies on the market, but due to the special industry of medical electronics, the requirements for its power supply are very high. To ensure the safety performance of human body and equipment, the choice of DC/DC module power supply is particularly important.

The application of DC/DC module power supply in the medical electronics industry, especially in sensor detection circuits, should pay attention to the following matters:

1. The external capacitor of the DC/DC power module should be a low internal resistance capacitor, and excessive capacitance should be avoided to prevent damage to the module caused by overcurrent during startup due to excessive capacitance
2. To ensure the long-term reliability of the module, it should be operated at 10% rated power or above to prevent unstable output voltage caused by no-load or light load, which may affect the circuit operation. If the power consumption of the load is indeed small, a dummy load (resistor) of -10% rated power can be added to the output terminal by connecting an external dummy load to improve the reliability of the product.
3. Due to the use of switch oscillation circuits in DC/DC power modules, they can also generate interference from common mode and differential mode noise. For applications that require high ripple noise, a passive filtering network can be externally connected to the output of the DC/DC power module to further reduce power ripple noise. However, it is important to note that the resonant frequency of the module should be much higher than the switching frequency of the module, and the allowed current value should be at least twice the input current of the module. The internal resistance should be small to reduce DC losses.