TI Integrates Smart Battery and Power Management Technology on Single Chip

September 19, 2005

Texas Instruments announced today a high-performance power conversion integrated circuit with "smart charging" capability that incorporates all essential power transistors onto a single device. Occupying up to 70 percent less board space versus discrete solutions, the programmable chip delivers high DC/DC conversion efficiency and battery management to one-cell lithium-ion (Li-Ion) powered communication and multimedia devices with multiple voltages, such as smart phones, portable audio and media players, satellite radio and GPS systems.

"Mobile consumers continue to demand more functionality while maintaining long battery life in smaller designs," said Gregg Lowe, senior vice president of TI's high-performance analog group. "Because of its leading analog manufacturing expertise, Texas Instruments is well positioned to integrate its high-performance building blocks to help our mobile handset and electronics customers meet stringent power requirements and get more out of their battery."

TI's TPS65800 power management unit integrates several power control building blocks, including two synchronous step-down DC/DC converters with integrated FETs, one boost DC/DC converter for white LED display backlight, an RGB LED driver, seven linear regulators (LDOs), a high-performance analog-to-digital data converter, SIM card and RTC power supplies and an I2C communications interface that allows full programmability of the TPS65800. In addition to the power regulation blocks, the device applies TI's patented linear charge and system power path management technology for Li-ion batteries using integrated charge FETs.

High DC/DC Conversion Efficiency

To conserve battery power, the DC/DC switch-mode converters support greater than 90 percent efficiency over a wide range of load currents, while deploying pulse frequency modulation (PFM) at light-load conditions. Two buck converters drive up to 600 mA for core and I/O requirements, and the boost converter illuminates up to six white LEDs in series. Three of the seven low-dropout voltage regulators (LDO) feature low noise and high power supply rejection ratio (PSRR) for RF and audio supplies. Additional regulators manage the voltage levels to a SIM data card used in wireless systems and a back-up supply for a real-time clock.

Smart Charging Capability

Dynamic power path management allows the TPS65800 to power the system while independently charging a one-cell Li-ion battery from either a USB or AC/DC wall adapter power source - all without adding any external power components. This feature reduces the charge and discharge cycles on the battery, allowing for proper charge termination and system operation with an absent or defective battery pack. In addition, the system can instantaneously turn on from an external power source in the case of a deeply discharged battery pack.

Flexibility Through Programmability

The TPS68500 features a serial interface, which is compatible with the standard and fast-mode I2C specifications, allowing data transfers at up to 400 kHz. The interface adds flexibility to the power supply solution and enables instant programmability reacting to changing system requirements. The device's integrated 10-bit A/D converter can be used for battery monitoring purposes, while three programmable general purpose I/O channels control other functions in the system.

Maximizing Use of Battery Power

To further maximize battery life and system run-time, TI focuses on three critical areas of the system. First, advanced battery management technology intelligently charges the battery and accurately measures its capacity. Second, switch-mode power conversion translates the battery power as efficiently as possible to supply system components. And third, new advancements in TI system power and performance management, such as SmartReflexTM technology, analyze and manage power consumption in the processor domain, while adaptively controlling the power supply through software to optimize the use of battery power.