As an application engineer, I know that the implementation of a buck regulator inevitably involves a trade-off between efficiency and size. Although this principle applies to many switch-mode DC/DC topologies, this principle does not necessarily apply when applications require low output voltages and high output currents (such as 1V and 30A), as this requires balanced efficiency and size. Small power solution. High efficiency is an important performance benchmark that not only reduces power loss and component temperature rise, but also brings more useful power for a given airflow and ambient temperature. From this point of view, the low switching frequency is very attractive, but at the same time requires large filter components to meet the requirements of target specifications such as output ripple and transient response, so the cost and size will increase. The PCB area dedicated to power management is a huge constraint for system designers. For this question, let us review the advantages of high switching frequency. First, the inductor and capacitor requirements decrease with increasing frequency, resulting in a more compact PCB layout and a smaller form factor. Lower inductors enable faster, larger signal current changes and higher control loop bandwidth, as well as faster load transient response. As a rule of thumb, the maximum loop bandwidth is 20% of the switching frequency. Finally, there are some interesting options for component selection at higher frequencies. For example, let's take a look at this regulator design, which allows for optimal efficiency/size/cost by carefully selecting components. Click here to watch the video demo . (1) Inductors —Although iron core inductors or combined core inductors provide good performance at low frequencies, higher core losses negate the value proposition of frequencies above 500 kHz. At this point, ultra-low DCR ferrite magnetic materials are easier to achieve lower copper losses and core losses. Note that the core loss is relatively easy to measure, just pay attention to the converter's no-load input current. Ferrite inductors with single-pin staple windings currently offer a wide range of off-the-shelf options, and if only one winding number is required, it is easy to achieve a DCR below 1mΩ! (2) PWM controller — Now, if the design specifically requires the hard saturation characteristics of the ferrite core inductor, it must not exceed the saturation current of the inductor. This requires a PWM controller that takes advantage of parasitic circuit resistance for accurate lossless current sensing (read my previous blog, "Improve Accurate, Lossless Current Sensing in High Current Converters" to learn more about this topic. More details). Other key features include high efficiency gate drivers, remote BJT temperature sensing, and fast error amplifiers. (3) MOSFETs - Power semiconductor devices are the basis for improved efficiency and size. Taking the power block NexFETTM series as an example, its well-known advantage is the innovative combination of high-side and low-side MOSFETs in a vertically stacked manner. Low QG, QRR, and QOSS charges are required when frequency proportional loss is a concern. In addition, low RDS (ON), high current copper clips, Kelvin gate connections, and grounding tabs are also important. (4) Capacitors - Ceramic capacitors are preferred over electrolytic capacitors at higher frequencies. A large amount of output energy storage has become superfluous because the control loop responds quickly to transient demands. Ceramic products not only provide lower ESR, but also provide lower ESL, which mitigates output ripple caused by inductor splitting effects and low filter inductance. What other factors affect the efficiency and size of the regulator? Recent popular topics include GaN MOSFETs, Power System Encapsulation (PSIP), and Power On-Chip Systems (PSOC). Please tell me what you think?
Plug-in Piece Sensor
Feyvan Electronics designs and manufactures NTC temperature sensors, probes, and cable assemblies with excellent long-term stability, high accuracy and short response time in high-temperature sensing applications such as automotive, home appliance and industrial use from -40℃ to +250℃.
With more than 15 years of NTC thermistors and sensor probes production experiences, Feyvan electronics provide various choices for a wide range of applications and are available in custom engineered probe package configurations for a variety of mounting and connectivity options with low costs.
Plug in Sensor,Sensor Coffee Maker,Sensor Coffee Machines,Automotive Sensors Feyvan Electronics Technology Co., Ltd. , https://www.fv-cable-assembly.com