LED drivers from TI cover range of dimmable LED lights and form factors

Marking what looks like the first introduction of a National Semi part under the new TI banner, TI has announced two new LED drivers, one with National heritage, and one from TI. The two parts roughly sort themselves out into two power categories: The LM3448 is optimized for 2W to 8W dimmable LED lighting drivers while the TPS92070 suits 6W to 20W dimmable LED lighting drivers. Both products feature thermal shutdown, VCC under-voltage lockout, cycle-by-cycle peak current limit and LED open protection.

The LM3448 is an adaptive constant-off time AC/DC constant current LED regulator with an integrated a 600V MOSFET that targets integrated LED lamp form factors that require low component count, high performance dimmable LED drivers, the LM3448 includes a phase angle dimming decoder compatible with leading edge TRIAC and trailing edge electronic dimmers allowing full-range LED dimming.  The integrated 600V avalanche-protected high voltage and low Rdson MOSFET reduces design complexity while improving LED driver efficiency.  The LM3448 can be used in both isolated and non-isolated solutions based on the buck, flyback or buck-boost topology using either active or passive (valley-fill) power factor correction (PFC) circuits.

The TPS92070 is a flyback AC/DC constant current LED driver controller designed for both uniform and dimmable LED drivers. It includes TRIAC dimmer management circuitry that decodes dimmer conduction angles and produces a visually-pleasing exponential LED current profile.  The TPS92070 is optimized for valley switching and tight LED current regulation (<5 percent driver-to-driver) during deep dimming.  The innovative secondary side feedback eliminates optocouplers and error amplifiers in isolated designs, reducing size and cost while enhancing safety reliability.  The TPS92070 can be used in both isolated and non-isolated solutions based on the flyback topology and allows flexible external component selection to be made for optimized size, cost and regulatory requirements.  The TPS92070 can detect the presence of a TRIAC and disable the external PFC function (either valley-fill or active) for improved dimming performance.

TI offers an online navigation tool that delivers a complete LED drive design tuned to a particular application’s including AC input voltage, fixture type, isolation and dimming requirements.  The recommended solution is provided along with design materials such as datasheets, application notes and evaluation boards.

The LM3448 is available in a 16-pin SOIC package priced at $1.10 (1,000). The TPS92070 is available in a 16-pin TSSOP package priced at $0.75 (1,000). (The higher price for the National part is likely due to the integrated FET.)