With the growth of digital liquid crystal display (LCD) TVs, which require 35 percent more power to operate than older cathode ray tube (CRT) TVs, energy demands from consumers are increasing rather than decreasing. Texas Instruments, aware of this trend and of the contribution that the digital switchover is making to spur the transition from analog to digital TVs, has launched two new power management chips to help mitigate the problem.
The first is a dual-phase power factor correction (PFC) controller that has been based on the previously announced UCC28060 PFC controller. The UCC28061 controller incorporates smaller electromagnetic interference (EMI) filters, smaller or fewer output capacitors and smaller boost inductor volume to result in thinner power supply designs, thus suiting thinner LCD TVs. Dual-phase transition-mode operation lowers overall system costs, and is simpler to design in than previously used continuous conduction mode controllers. Meanwhile, the device boasts phase management and burst mode features that realise energy efficiencies at various power levels. Notably, the UCC28061 suits ENERGY STAR and 80 Plus efficiency standards.
The second product designed for digital LCD TVs, it the SWIFT DC/DC power management converter. The TPS54331 converter, which supplies up to 3-A output current, reduces the power consumption of LCD TV point-of-load circuit board designs. Thanks to a new switching technique that TI calls Eco-mode, the device has an 110-A operating current and low 1-A shutdown current. This light-load is said to increase energy efficiency by more than 25 percent compared to conventional DC/DC converters. Other features include a wide input range of 3.5 V to 28 V and an output voltage adjustable down to 0.8 V.
The UCC28061 and TPS54331 are available in 16-pin and 8-pin SOIC packaging, respectively. Reference designs, evaluation modules and the SwitcherPro software tool for the TPS54331 are also available online at www.ti.com/tps54331evm.