Beijing, April 7, 2021 / AP / — Texas Instruments (TI) (NASDAQ Code: TxN) today launched a new series of synchronous DC / DC Buck controllers, which support engineers to reduce the size of power solutions and reduce their electromagnetic interference (EMI). Lm25149-q1 and lm25149 adopt integrated active EMI filter (AEF) and dual random spread spectrum (DRSS) technology, which enables engineers to halve the area of external EMI filter, reduce conducted EMI of power supply design by up to 55 dB μ V in multiple frequency bands, or reduce filter size and EMI at the same time. For more information, see and .
Reducing EMI in power supply is an increasingly serious design challenge, especially with the increase of electronic components in advanced driving assistance system (ADAS), automotive infotainment system and instrument cluster, building automation, aerospace and national defense design. Previously, the way to ensure that the design meets the conducted EMI specification is to increase the size of the external passive EMI filter, which increases the overall size of the power supply solution. Through the integrated active EMI filter, lm25149-q1 and lm25149 buck controller, engineers can meet the EMI standard and improve the power density of the design. To understand the working principle of integrated active EMI filter, please read the technical article “how to reduce EMI and power supply size through integrated active EMI filter”.
Reduce the conducted EMI of the whole CISPR 25 class 5 standard involving the spectrum
CISPR 25 class 5 standard of International Special Committee on radio interference puts forward strict industry requirements for low EMI design in automotive environment. Lm25149-q1 and lm25149 buck controllers can help engineers meet these requirements by reducing conducted EMI in multiple frequency bands. The integrated active EMI filter helps detect and reduce conducted EMI in the 150 kHz to 10 MHz low frequency band, enabling engineers to reduce EMI by up to 50 dB μ V (at 440 kHz switching frequency, relative to the design with AEF disabled) or 20 dB μ V (relative to the design with typical passive filters). In both designs, DRSS technology helps to further reduce EMI by 5 dB μ V in the low and high frequency bands.
In order to further reduce EMI, the working frequency of these two buck controllers are synchronized with the external clock, which helps engineers reduce bad beat frequency in EMI sensitive applications. To learn more about EMI reduction technologies, read the white paper reducing EMI in power supplies through innovative technologies that save time and cost.
Reduce external EMI filter while reducing solution cost to a greater extent
In the design of switching power supply, the realization of low EMI power supply and small solution size are usually contradictory. The lm25149-q1 and lm25149 buck controllers support engineers to meet challenging EMI standards and reduce the size of the solution by reducing the area and volume of passive EMI filters. Compared with similar solutions, at 440 kHz, engineers can reduce the area and volume of front-end EMI filters by nearly 50% and 75% respectively. By reducing the filter load of the passive components, the integrated AEF can reduce the size, volume and cost of the passive components, so that engineers can realize the design of smaller low EMI power supply.
Lm25149-q1 and lm25149 controllers further improve power density and reduce design complexity and cost by implementing interleaved two-phase operation and integrating bootstrap diode, loop compensation and output voltage feedback components. Engineers can also use external feedback and loop compensation to further optimize their design.
Package and supply
The 42V lm25149-q1 and lm25149 in a 3.5mm x 5.5mm thermally enhanced 24 pin vqfn package are now pre produced, but only through Provide. At the same time, lm25149-q1evm-2100 evaluation module is provided. Provides a variety of payment and delivery methods. Ti expects 42V versions of lm25149-q1 and lm25149 to go into mass production in the fourth quarter of 2021. In addition, Ti is developing lm25149-q1 and lm25149 pin to pin compatible 80V versions.