Small and efficient Simple Switcher synchronous converters to simplify the design of industrial power supplies

Texas Instruments (TI) introduced two wide-V_IN 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 0.5A/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.

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 V_IN, 5 V_OUT, 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 13.8ºC/W (Ψ_JB) 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.