November 6, 2013 – Linear Technology Korea (CEO Hong Sa-gwak) announced the launch of a high-performance high-voltage power manager and multi-battery charger (product name: LTC4020) designed to efficiently transfer power from various sources to system power supplies and batteries.

This device provides precision charge current regulation and ±0.5% charge voltage regulation, operating over a wide input voltage range of 4.5V to 55V compatible with different input voltage sources. With maximum output voltage of 55V and three selectable termination algorithms, the LTC4020 uniformly accommodates various battery stack voltages and battery types. The LTC4020 includes a step-up/step-down DC/DC controller and can operate at battery voltages higher than, lower than, or equal to the input voltage (VIN). Typical applications include portable industrial and medical equipment, solar-powered systems, military communication equipment, and embedded automotive systems of 12V to 24V.

The LTC4020 features an intelligent PowerPath™ topology that reduces the voltage range required by downstream system components from the full range of the input voltage source to the predicted battery voltage range. However, the instant-on function continues to ensure system load power from a completely discharged battery. Additionally, this topology prioritizes power delivery to the system load when input power is limited. The device's ideal diode controller ensures that sufficient power is always available at VOUT when there is insufficient power available in the DC/DC converter. The maximum power point control (MPPC) circuit features an input voltage regulation loop. This loop controls the charge current to maintain the input voltage at a programmed level, making it ideal for high-impedance inputs or solar energy-powered applications. When input power is absent, the quiescent current on the battery side is reduced to as low as 10μA, maintaining maximum stored capacity.

The LTC4020's three pin-selectable charge profiles are optimized for various battery types. The LTC4020 can provide constant current/constant voltage (CC/CV) charge characteristics with C/10 or time-based termination for use in lithium-based battery systems including lithium-ion (Li-Ion), lithium polymer (Li-polymer), and LiFePO4. Constant current (CC) characteristics with time-based termination can be used for charging supercapacitors or trickle charging nickel-based batteries. Finally, four-stage and three-stage lead-acid charge profiles work well with all types of lead-acid batteries including sealed, AGM, and flooded types. An integrated timer not only controls termination during CC/CV charging, but also controls additional protection during battery preconditioning and absorption charging for lead-acid batteries. Two digital open-drain outputs provide charge status and error condition signaling. These binary-coded pins signal battery charging, standby or shutdown mode, battery temperature error, and battery fault error. Other features of the battery charger include temperature-qualified charging using an NTC thermistor, automatic recharge, or low-current preconditioning charge for completely discharged cells.

The LTC4020 is offered in a low-profile (0.75mm) 38-pin 5mm x 7mm QFN package with a metal pad on the back for excellent thermal performance. This device is guaranteed to operate in the range of -40°C to 125°C. It is supplied at $4.95 per unit based on 1,000-unit quantity. Detailed information is available at www.linear.com/product/LTC4020.