TI Boost Converter Enables Solar and Micro-Fuel Cell Innovation in Portable Electronics
0.3-V Input Power Management Chip with 0.5-V Start-Up Allows Battery-Driven Devices to Tap New Wave of Low-Power Energy Sources
DALLASTexas Instruments Incorporated (TI) introduces the industry's lowest input voltage DC/DC boost converter, which will enable portable electronic end-equipment to draw power from new energy sources, such as solar and micro-fuel cells. The tiny power circuit can operate with input voltages lower than 0.3 V with high efficiency, allowing designers to overcome the low-voltage design barrier of incorporating these alternative energy sources in applications, such as mobile phones, portable medical devices and media players.
The new TPS61200 step-up converter with integrated 1.5-A switch supports input voltages of 0.3 V to 5.5 V during normal operation, and continues to manage power down to 0.0 V if the under-voltage lockout pin is connected directly to the output voltage. The converter provides an extremely low 0.5-V start-up capability in any load condition, and can operate with more than 90 percent efficiency. In contrast, today's best step-up converters can only support an input voltage beginning at 0.7 V with start-up at 0.9 Vgood for primary re-chargeable battery cells or main supplies, but not low enough to support new applications using energy harvesting power sources.
The TPS61200's ability to operate from a single solar cell eliminates the need for multiple solar cells in series, and eliminates the required protection circuitry associated with series connection. This opens the door to new potential innovative designs, such as a built-in solar-powered cell phone charger that uses indoor ambient lighting to help provide an infinite amount of standby time.
"Portable equipment designers, including those in the portable medical, wireless and portable audio fields, are continuing to look at how to apply solar and fuel cell technology into their devices to extend battery life and differentiate their products," said Uwe Mengelkamp, director of TI's DC/DC converter product line. "It's not certain what we will see first, but the ideas are endless. What is certain is that designers can use the TPS61200 to achieve low-voltage operation to connect these new low-power energy sources with the ICs in their system."
Protecting the System at Low Voltages
The TPS61200, which comes in a 10-pin, 3 mm x 3 mm QFN package, offers several features that are critical during low-voltage operation, including output short-circuit protection, programmable under-voltage lockout and a unique "down-conversion mode" that helps protect the device when an input voltage rises higher than the output voltage. In addition, the converter can be disabled to further minimize battery drain. While the end equipment shuts down, the TPS61200 protects the system from receiving any additional power from the battery.
Extends the Operating Range of Single-Cell Alkaline, NiCd and NiMH Batteries
The integrated circuit's extremely low operating voltage also eliminates many of the design challenges that occur when operating a single-cell Alkaline, nickel-cadmium (NiCd) and nickel-metal hydride (NiMH) batteries to power anything from toys to portable medical devices. The TPS61200 extends the operating time of many pulsed-load applications that experience pass-load conditions at low-voltage inputs.
SwitcherPro and TINA-TI 7.0 Design Tools
Designers can simplify power design with the TPS61200 by leveraging TI's new Analog eLab Design Center, www.ti.com/analogelab. The recently announced design center features TI's SwitcherPro power supply design tool and a new release of TINA-TI 7.0 simulation environment, which includes switch-mode power supply simulation with acceleration.
Pricing and Availability
The TPS61200 boost converters are available today in volume from TI and its authorized distributors. The device comes in a 3 mm x 3 mm, 10-pin QFN package. Suggested resale pricing in quantities of 1,000 units is $1.68. The TPS61200EVM-179 evaluation module, application notes and TI's new Power Management Selection Guide are available through power.ti.com.