Linear Tech Releases Switching Power Manager With USB On-The-Go & Overvoltage Protection
Linear Technology Corp. announced the LTC4160 and LTC4160-1, the latest members in a family of power manager ICs for single-cell Li-Ion/Polymer battery-based applications, including media players, personal navigation devices, digital cameras, PDAs and smart phones.
The LTC4160/-1 features a bidirectional switching power manager which can power an application and charge the battery from USB. Operating in reverse, the same switching regulator can take power from the battery to generate 5V and deliver up to 500mA for USB On-The- Go (OTG) applications without any additional components. The LTC4160/-1 includes automatic load prioritization when powered from USB, input overvoltage protection, a standalone battery charger, and an ideal diode, all in a compact, ultralow profile (0.55mm) 3 x 4mm UTQFN package. The LTC4160-1 offers a 4.1V battery float voltage, allowing high temperature safety margin, while the LTC4160 features a 4.2V final charge voltage for optimized battery run time.
The on-chip switching regulator also features programmable input current limits of 100 and 500mA for enhanced USB compatibility, as well as a wall adapter input current limit setting up to 1.2A. For fast charging, the LTC4160/-1 converts nearly all of the 2.5W available from the USB port to charging current, enabling up to 600mA of charge current from a 500mA limited USB supply and up to 1.2A of charge current from a wall adapter. The device provides an overvoltage protection (OVP) control circuit that prevents damage to its input from the accidental application of high transient voltages. The OVP circuit can protect the USB port even when the IC is providing power for USB OTG.
The LTC4160/-1’s PowerPath™ control with automatic load prioritization seamlessly manages power flow between a variety of input power sources such as a wall adapter or USB port and the Li-Ion/Polymer battery while preferentially providing power to the system load. The IC’s "Instant-ON" operation ensures system load power even with a fully discharged battery. The LTC4160/-1’s switching regulator features Bat-Track™ adaptive output control which greatly improves the efficiency of its battery charger by maintaining the output voltage approximately 300mV above the battery voltage. An internal 180mΩ ideal diode plus optional external ideal diode controller provide a low loss power path from the battery to the load when input power is limited or unavailable. The LTC4160/-1’s stand-alone battery charger features autonomous operation that simplifies design and eliminates the need for an external microprocessor for charge termination. To preserve battery energy, the LTC4160/-1 draws < 4uA from the battery in suspend mode and < 8uA in ideal diode mode.
The LTC4160 and LTC4060-1 are available from stock in a compact, ultrathin (0.55mm) 3 x 4mm 20-pin QFN package. Pricing starts at $2.85 each for 1,000-piece quantities.
