The MAX14745JEWX+T is a battery-charge-management solution ideal for low-power wearable applications. The device includes a linear battery charger with a smart power selector and several power-optimized peripherals. The MAX14745JEWX+T features two ultra-low quiescent current buck regulators and three ultra-low quiescent current low-dropout (LDO) linear regulators, providing up to five regulated voltages, each with an ultra-low quiescent current, allows designers to minimize power consumption and extend battery life in 24/7 operation devices, such as those in the wearable market.
The battery charger features a smart power selector that allows operation on a dead battery when connected to a power source. To avoid overloading a power adapter, the input current to the smart power selector is limited based on an I2C register setting. If the charger power source is unable to supply the entire system load, the smart power control circuit supplements the system load with current from the battery. The charger also supports temperature dependent charge currents.
The two synchronous, high-efficiency step-down buck regulators feature a variable frequency mode for increased efficiency during light-load operation. The output voltage of these regulators can be programmed through I2C with the default preconfigured. The buck regulators can support dynamic voltage scaling to further improve system power consumption.
The three configurable LDOs each have a dedicated input pin. Each LDO regulator output voltage can be programmed through I2C with the default preconfigured. The linear regulators can also be configured to operate as power switches that may be used to disconnect the quiescent load of the system peripherals.
The MAX14745JEWX+T features a programmable power controller that allows the device to be configured for applications that require the device be in a true-off, or always-on, state. The controller also provides a delayed reset signal and voltage sequencing.
The MAX14745JEWX+T is available in a 36-bump, 0.4mm pitch, 2.72mm x 2.47mm wafer-level package (WLP).
Feature
- Extend System Use Time Between Battery Charging
- Dual Ultra-Low-IQ 200mA Buck Regulators
- Output Programmable from 0.8V to 2.375V and 0.8V to 3.95V
- 0.9μA (typ) Quiescent Current (Buck 1)
- Optional Fixed Peak-Current Mode to Optimize Ripple Frequency in Noise-Sensitive Applications
- Three Ultra-Low-IQ 100mA LDOs
- LDO1
- Output Programmable from 0.8V to 3.6V
- 0.6μA (typ) Quiescent Current
- 2.7V to 5.5V Input with Dedicated Pin
- LDO2/3
- Output Programmable from 0.9V to 4V
- 1μA (typ) Quiescent Current
- 1.71V to 5.5V Input with Dedicated Pin
- Dual Ultra-Low-IQ 200mA Buck Regulators
- Easy-to-Implement Li+ Battery Charging
- Smart Power Selector
- 28V/-5.5V Tolerant Input
- Thermistor Monitor
- Minimize Solution Footprint Through High Integration
- Provides Five Regulated Voltage Rails
- Switch Mode Option on Each LDO
- Optimize System Control
- Monitors Pushbutton for Ultra-Low Power Mode
- Power-On Reset Delay and Voltage Sequencing
- On-Chip Voltage Monitor Multiplexer
Applications
- Fitness Monitors
- Rechargeable IoT devices
- Wearable Electronics
