Linear Technology Corp. (LTC, Milpitas, CA) introduced the new LTC4008, a 4A, multi-cell, multi-chemistry, battery pack charger with a solution size of only 5.6cm². The LTC4008 also reduces the cost of a charger design by eliminating the need for more than 40 percent of the discrete components. When interfaced with a microcontroller, the LTC4008 is capable of charging nickel-cadmium, nickel-metal hydride and sealed lead-acid batteries as well as lithium-ion. Typical applications include battery charger cradles, uninterruptible power supplies, portable data terminals and notebook PCs.
The LTC4008 drives external MOSFETs synchronously to achieve over 95 percent efficiency even when operating from high input voltage and delivering up to 4A of charge current. The LTC4008 guarantees no audible noise operation with all types of output capacitors, including ceramic. Charging current is programmable to ±4 percent accuracy with external resistors. The LTC4008's ac adapter current limit allows an end product, such as a notebook PC, to operate simultaneously as the battery pack is being charged at the maximum rate without overloading the ac adapter. Moreover, the LTC4008 includes a thermistor sensor input that will suspend charging if an unsafe temperature condition is detected, and will automatically resumes charging when battery temperature returns to within safe limits.
The LTC4008 is offered in a 20-pin SSOP package. Pricing for 1,000-unit quantities starts at $3.70 each.
