Integrated switching regulators often come with compact, optimized, and tested PCB layouts which reduce the design cycle and time to market.īecause the environment of modern telecom systems demands higher performance along with smaller size and less floor space, PCB real estate is increasingly valuable. Moreover, the pin configuration of an integrated switcher is designed to preclude questions that would otherwise be faced about component location and grounding. Integrated switching regulators, in contrast, avoid many layout problems by integrating the power stage (MOSFETs and gate drivers) and current sensing within the device to eliminate several PCB interconnects. Most of these problems can be traced to the higher probability of layout mistakes when implementing a power supply containing several discrete external components. Those problems include improper power-stage layout, incorrect grounding schemes, routing of sensitive analog traces near power traces that carry rapidly changing currents and voltages, failure to provide Kelvin connections for voltage and current sensing, excessive EMI, and the location of decoupling capacitors. Apart from the time required for PCB layout, a major part of power-supply development consists of fixing layout-related problems. They are well suited to the distributed-power requirements of modern telecom boards, which require compact, multiple, point-of-load power supplies that provide an excellent transient response to dynamic loads.ĭesign, development, and testing of the power supply for a telecom system board represents a substantial part of that board's development time. What is new is the increased current capability and enhanced features now provided by such devices. The integrated switcher, which combines the MOSFETs, gate drivers, and PWM controller of a DC-DC switching converter within a single package, is not a new concept. In the past two decades, manufacturers of power-management ICs have done a tremendous job of producing devices that integrate many of the functional blocks required in power supplies for isolated and nonisolated DC-DC conversion applications. Many areas of the electronics business, including the power-electronics industry, employ a strategy that integrates system components to reduce overall cost, enhance reliability, and minimize valuable real estate on the PC board. Compared with the conventional power-distribution architecture for telecom boards (left side), the integrated switching-regulator architecture (right side) offers better efficiency and reliability, faster design, and a smaller footprint.īenefits of an Integrated Switching Regulator Integrated switching regulators are excellent candidates for this second power-conversion stage, because the required input voltage (≤ 12V) and output current (< 10A) are both relatively low.įigure 1. Such voltage conversions can be achieved with nonisolated, point-of-load power supplies as shown on the right side of Figure 1. The intermediate voltage is then converted to the system voltages required for specific loads. Improved performance can be obtained by using a single isolated, high-power DC-DC module to convert 48V to an intermediate supply rail of 12V or less. ![]() Such devices impose stringent requirements on the power supply: very fast transient response, high efficiency, lower voltage rails, and a reduced footprint area. That configuration, however, poses difficulties in meeting the load requirements of fast, low-voltage processors, DSPs, ASICs, and DDR memories. Traditional distributed-power architectures employ several isolated DC-DC power modules to convert a 48V bus voltage to system supply-voltage rails such as 5V, 3.3V, and 2.5V.
0 Comments
Leave a Reply. |