Low battery warnings always leave users in a quandary, unsure how much longer they can use a portable product before they're going to regret it. Microchip Technology Inc. is offering a battery monitor that provides more precise information, as well as shutting down ancillary processes so critical jobs can be completed before the battery fails.
Addressing another aspect of power management in portables, the company is also unveiling battery-charging controllers that make sure batteries are fully charged without raising concerns that come with over-charging.
The battery monitor chipóthe PS700ómonitors the voltage, current and temperature of a battery with resolutions of 9-16 bits, so its status can be precisely monitored. The temperature sensor and regulator are on the chip, saving space over other alternatives. It provides enough accuracy so users know whether or not they can start another function.
"You can see when your batteries are low and you can complete critical jobs without concern about the system crashing," says Jim Vernon, vice president of Microchip's battery management group. He adds that the price point of $1.45 in 1,000-lot quantities marks the first time that this type of monitoring precision is within the price range for handheld consumer devices.
The charge-management controller line works with Lithium-Ion and Lithium-Polymer batteries, providing voltage regulation accuracy to 0.5%. The MCP7384x family has cell preconditioning to aid in recharging severely depleted batteries, as well as a temperature monitor that prevents charging outside of optimal ranges. "Higher regulation accuracy avoids the safety issues with overcharging, but also avoids undercharging when you don't use the full capacity," says George Paparrizos, senior marketing manager for Microchip's Analog and Interface Products.
It also works with loosely regulated adapters, accepting inputs up to 12V. Some low-cost adapters have wide variances, which can impact recharging, Paparrizos adds. The chips can work with an external field effect transistor (FET) to shorten charging times for high-capacity battery packs.