Linear Technology yesterday introduced its LT3651-4.2 battery charger for 1-cell Li-Ion/Polymer batteries. The LT3651-4.2 accepts inputs up to 32V (with a 40V absolute maximum rating for added system margin). Charge current is programmable and dynamically adjustable up to 4A.
Synchronous operation minimizes power dissipation and enables charging efficiencies as high as 90%. Once charging is terminated, the LT3651-4.2 automatically enters a low current standby mode which reduces the input supply current to 80uA. In shutdown, the input bias current is reduced to 15uA.
The LT3651-4.2 also does not require external high-precision resistors to set the float voltage, saving cost and space.
Applications include industrial handheld instruments, 12V to 24V automotive and heavy equipment applications, desktop cradle chargers and notebook or tablet computers.
The LT3651-4.2 comes in a low-profile (0.75mm) 36-pin 5mm x 6mm QFN package and is offered in both E and I grade versions. Pricing starts at $4.13 and $4.75 each, respectively, in 1,000-piece quantities.Two-cell 8.2V and 8.4V options and a one-cell 4.1V version are planned for release within the next 2-3 months.