Board mount power supplies are devices that convert electrical power from a source into a format that can be utilized to empower a specific load and are meant to be physically and mechanically attached within an application by attaching to a printed circuit board. A power supply is an electrical device that provides electricity to a load. The principal function of a power supply is to switch electric current from a primary source to the proper voltage, current, and frequency to power a load.
Power supplies are sometimes referred to as electric power converters because of this. Most power supplies are freestanding components; however, some are integrated into the load appliances they power. Power supply seen in desktop computers and consumer electronics devices are examples of the latter.
Other functions of power supplies include: limiting the current drawn by the load to safe levels, shutting down the current in the event of an electrical fault, power conditioning to prevent electronic voltage surges on the input from reaching the load, power-factor correction, and storing energy so that it can continue to power the load even if the source power is temporarily interrupted.
More than merely converting between AC and DC power is involved in PCB power supply design. There are power and signal integrity issues to consider and thermal management issues that arise with high-power electronics. Because of how ICs work, signal and power integrity are inextricably linked, and some power supplies can emit considerable radiated EMI that impacts other circuit board components.
No power supply or the system to which it is attached is immune to signal integrity or power integrity issues, but following a few simple design procedures will help you avoid a redesign. Everything from correct component layout to decoupling/bypassing and stack-up design is covered in these best practices.
1. Unregulated(also known as brute force)
2. Linear regulated
3. Switching
The first step in setting up a power supply is to decide which type of power supply you’ll need for your gadget. Unregulated power supplies are a cheap and unclean way to convert AC electricity from a wall outlet to DC. Because the output is not smoothed with a regulator, the output from these supplies will have a ripple waveform. Modern applications rely on a regulated power source to reduce ripple.
There are two principal options for regulating DC output from power supplies: a linear regulator or a switching regulator called a switch-mode power supply. These power supplies pass the DC output from a full-wave rectifier to a regulation circuit, which smooths the ripple waveform superimposed on the desired DC output. These regulators can also directly control a DC power source, such as a battery. Linear regulators themselves have very low noise, but they tend to be large due to the usage of heatsinks or other active cooling mechanisms for thermal management. The low efficiency of these power sources can be attributed to their high heat dissipation.
On the other hand, a switched-mode power supply has a substantially higher efficiency over a wider current range, allowing for smaller form factors. These power sources use a PWM circuit to smooth and regulate the output voltage, necessitating an active switching component (normally a MOSFET). Consequently, the system emits a lot of EMI, and the output will have spikes from switching noise. This switching noise can show on the output as a ringing signal (i.e., conducted EMI), and it needs to be filtered out.
Linear and switching regulators can be found in integrated circuits for low-power applications. These ICs are perfect for mobile devices and other low-power gadgets that may be plugged into a wall socket. However, regardless of the power consumption in your device, there are some basic PCB design considerations to take into account to ensure power integrity and signal integrity.
There are several circuits you should consider adding to your board depending on the type of regulator used in your power supply. Some simple layout choices can help suppress conducted and radiated EMI. In extreme cases, you may need to add shielding in your board, such as with a high current power supply or a switching regulator in general, to ensure signal integrity in neighboring circuits.
Apart from Power Supply manufacturers, purchasers can rely on the electronics distributor networks at BD Electronics Ltd. Our customers worldwide benefit from our high-quality service and delivery of industry-leading, high-performance capacitance solutions. In addition, a comprehensive line of power supply board mounts is available to order from BD Electronics Ltd.
The company has developed a strong network of suppliers and partnerships with various manufacturers within the industry. This allows us to meet all of the customers’ demands for electronic modules with a short lead time. At BD Electronics Ltd., we can provide our customers with professional service, the most reasonable quotes in the market, and rapid delivery of the goods while maintaining the highest standards of the components’ form, fit, and functionality.
