Milpitas, Calif. Linear Technology Corp. has released the latest device in a family of next-generation, multi-function power management solutions for Li-ion/polymer battery applications. The LTC3566 switch-mode USB power manager integrates a switching PowerPath manager, a stand-alone battery charger, a 1-A high-efficiency synchronous buck-boost regulator, an ideal diode and controller, plus an always-on LDO, in a compact, low-profile (0.75 mm) 4 x 4-mm QFN-24 package.
The LTC3566's PowerPath control feature manages power flow between multiple input sources such as a wall adapter or USB port and the lithium battery while preferentially providing power to the system load. In addition, its "instant-ON" operation ensures power to the system load even with a dead battery. For fast charging, the LTC3566's switching input stage converts nearly all of the 2.5 W available from the USB port to charging current, enabling up to 700 mA from a 500 mA limited USB supply and up to 1.5 A when wall powered. An internal 180-milliohm ideal diode plus optional external ideal diode controller provide a low loss power path from the battery to the system load, to further minimize heat generation and maximize efficiency, said Linear Tech.
The onboard synchronous buck-boost regulator can deliver up to 1 A continuously and is well-suited for efficiently regulating a 3.3-V output voltage over the full lithium battery voltage range, down to 2.75-V input. The regulator's internal low RDS(ON) switches enable efficiency as high as 94%, maximizing battery run time. In addition, burst mode operation optimizes efficiency at light loads with a quiescent current of only 20 uA (< 1 uA in shutdown).
The high 2.25-MHz switching frequency allows the use of tiny capacitors and inductors less than 1 mm in height. In addition, the regulators are stable with ceramic output capacitors, achieving very low output voltage ripple.
The LTC3566 features USB-compatible programmable current limiting to 100 mA/500 mA/1A, while its Bat-Track adaptive output control enables high-efficiency battery charging and reduces power dissipation. Stand-alone autonomous operation simplifies design, eliminating the need for an external microprocessor for battery charge termination, said Linear. To preserve battery energy, the LTC3566 draws only 38 uA in suspend mode. The charger is compatible with inputs up to 5.5 V (7-V absolute maximum transient).
Linear Technology will showcase its portfolio of high-performance analog and power management ICs at APEC 2008 in booth 132/134.
Pricing: Starts at $3.85 each in quantities of 1,000.
Availability: From stock.
Linear Technology, www.linear.com