Renesas Electronics ISL9120 Low Power Buck-Boost Regulator

Renesas Electronics ISL9120 Low Power Buck-Boost Regulator is a highly integrated DC-DC switching regulator that accepts input voltage above or below the regulated output voltage. The ISL9120 automatically transitions between buck and boost modes without significant output disturbance. The ISL9120 also has automatic bypass functionality. When the input voltage is generally within 1% to 2% of the output voltage, there will be a direct bypass connection between the V_IN and V_OUT pins. In addition to the automatic bypass functionality, the ISL9120 has forced bypass functionality using the BYP pin.

The ISL9120 can deliver up to 800mA of output current (V_IN = 2.5V, V_OUT = 3.3V) and provides excellent efficiency due to its adaptive current limit Pulse Frequency Modulation (PFM) control architecture.

The ISL9120 is designed for stand-alone applications and supports a 3.3V fixed output voltage or variable output voltages with an external resistor divider. The forced bypass power saving mode can be chosen if voltage regulation is not required. In forced bypass mode, the ISL9120 consumes less than 3.5μA of current over the operating temperature range.

The ISL9120 requires only a single inductor and very few external components. The ultra-small form factor of the ISL9120 makes it ideal for the connected devices making up the Internet of Things, including wearables, smartphones, smart thermostats, and point-of-sale devices.

Features

Accepts input voltages above or below the regulated output voltage
Automatic bypass mode functionality
Automatic and seamless transitions between buck and boost modes
Wide 1.8V to 5.5V input voltage range
Selectable forced bypass power saving mode
Adaptive multilevel current limit scheme to optimize efficiency at low and high currents