Highly integrated, wide-Vin DC/DC buck regulators simplify the design of industrial power supplies
Texas Instruments (TI) introduced two wide-VIN synchronous SIMPLE SWITCHER® DC/DC buck regulators in ultra-small HotRod™ quad flat no-lead (QFN) packaging. The highly integrated 3-A LMR33630 and 2-A LMR33620 step-down voltage converters feature the industry's best full load efficiency – 92 percent – for rugged and reliable industrial power supplies with switching frequencies up to 2.1 MHz. Used in conjunction with TI's WEBENCH® Power Designer, the converters simplify power conversion and speed the design process.
The 3.8-V to 36-V LMR33630 and LMR33620 buck regulators are offered in 3-mm-by-2-mm thermally enhanced packaging. The small HotRod QFN package includes unique wettable flanks enabling post-solder optical inspection to simplify manufacturing and gives the LMR33630 the industry's highest 0.5 A/mm2 power density at 3 A of current. Optimized package construction and symmetrical pin placement minimizes parasitic inductance and facilitate optimal placement of input bypass capacitors to mitigate conducted and radiated noise emissions.
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Efficiency of LMR33630 vs Output Current VOUT = 5 V, 400 kHz, VQFN. |
Key features and benefits of the LMR33630 and LMR33620
The new DC/DC converters provide an operating input voltage range as high as 36 V for nominal 12-V or 24-V systems such as factory and home automation, motor drives, inverters and servo control units. For applications up to 60 V, TI offers the 600-mA LMR36006 and 1.5-A LMR36015 synchronous step-down converters in pin-compatible packages.
The 36-V regulators feature full load efficiency of 92 percent at 24 VIN, 5 VOUT and a 400-kHz switching frequency. Very low 24-µA typical standby quiescent current increases light load efficiency.
In addition to the QFN package, the 36-V regulators are also available in a thermally efficient, 8-pin, 5-mm-by-6-mm small-outline integrated circuit (SOIC) package that delivers an ultra-low thermal coefficient of 13.8 °C/W (ΨJB) to further improve reliability.
Packaging, pricing and availability
Available through the TI store and authorized distributors, the 36-V LMR33630 and LMR33620 are priced in small reels at US$1.86 and US$1.75, respectively, for 1,000-unit quantities. The 60-V LMR36015 and LMR36006 are priced in small reels at US$1.84 and US$1.61, respectively, for 1,000-unit quantities through the TI store. All four devices are available in the 12-pin HotRod package.
Available in the 8-pin SOIC package, the 36-V LMR33630 and LMR33620 are priced in small reels at US$1.62 and US$1.52, respectively, in 1,000-unit quantities.
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The LMR33630ARNXEVM Evaluation Module. |