The MAX14676, recently introduced by Maxim Integrated, tries to extend the battery life of wearable devices by managing how power flows through these devices. This integrated circuit includes a 1.8V buck regulator that exhibits a typical quiescent current of 900nA and 74% efficiency with 10 µA output.
Wearable devices contain embedded processors, displays, and wireless chips for transmitting data—all of which are a significant drain on small batteries. Not all these systems are in constant operation, however, so the MAX14676 is designed with a fixed-frequency pulse width modulation (PWM) and burst modes for increasing efficiency during both normal and light load operations.
The MAX14676 also contains a linear battery charger that can operate on a dead battery and limits input current up to 28V based on a register setting. In the event that the power source is unable to support the full system load, a power control circuit will supplement the system load with current from the battery. In addition, the device has a fuel gauge that estimates the available battery capacity.
The MAX14676 comes in a 0.5mm package. It features 3.2V 100mA low-dropout regulator, an always-on 2.0V 50 µA LDO, a +5V safe output LDO, and a 6.6V 120 µA charge pump. For controlling power to displays, the device comes with a 5V to 17V output boost converter and three-channel programmable current sinks.