Dallas - Responding to the need for maximum power management at the microwatt level in increasingly functional 2.5- and third-generation mobile handsets and PDAs, Texas Instruments Inc. is billing its bq270x0 chip, called bqJunior, as a fully integrated battery fuel gauge for systems powered by a single-cell lithium-ion or lithium-polymer battery.
"As battery-powered consumer devices become more complicated and dynamic, designers of those products will require the right intelligent hardware to provide accurate information about the battery and system run-times to better manage available power," said Peter Fundaro, worldwide marketing manager for battery management products at TI. "This IC simplifies the design of a cost-effective, accurate battery fuel gauge in single-cell applications" by performing "all the necessary intelligent calculations on-chip, significantly reducing the amount of calculations performed by the host-side microcontroller," he said.
In operation, the bq270x0's on-board processor measures the battery's charge and discharge currents to within 1 percent using a low-offset volt-age-to-frequency converter. An analog-to-digital converter is used in the measurement of battery voltage and temperature. Also on-chip is an internal time-base E2PROM for configuring specific system parameters. The bqJunior runs its algorithm on the input data.
In a typical application, the host system reads the output data set to retrieve the remaining battery capacity, run-time, available power, average current, temperature, voltage, and time to empty and full charge. A single-wire communications port transfers the contents of the data set to the system host controllers.
The chip, which leverages the company's new LBC4 CMOS process for its high-integration and low-power advantages, draws less than 100 microamps in operation.
Samples of the bqJunior are currently available to select customers, with volume production scheduled for the second quarter. It's packaged in an eight-pin TSSOP or QFN (3 by 4-mm) package. The per-piece price is $2.55 in quantities of 1,000.
Call (800) 477-8924