ISL91127

DATASHEET ISL91127 High Efficiency Buck-Boost Regulator with 4.5A Switches FN8418 Rev 5.00 Jan 28, 2022 The ISL91127 is a high-current, buck-boost switching regulator for systems using new battery chemistries. It uses the Renesas proprietary buck-boost algorithm to maintain voltage regulation while providing excellent efficiency and very low output voltage ripple when the input voltage is close to the output voltage. The ISL91127 can deliver at least 2.1A continuous output current (VOUT = 3.3V) across a battery voltage range of 2.5V to 4.35V. This maximizes the energy utilization of advanced, single-cell Li-ion battery chemistries that have significant capacity left at voltages below the system voltage. Its fully synchronous low ON-resistance 4-switch architecture and a low quiescent current of only 30µA optimize efficiency under all load conditions. The ISL91127 supports stand-alone applications with a fixed 3.3V or 3.5V output voltage or adjustable output voltage with an external resistor divider. Output voltages as low as 1V or as high as 5.2V are supported. The ISL91127 is available in a 20 bump, 0.4mm pitch WLCSP (2.15mmx1.74mm) with a 2.5MHz switching frequency, which further reduces the size of external components. Features Accepts input voltages above or below regulated output voltage Automatic and seamless transitions between Buck and Boost modes Input voltage range: 1.8V to 5.5V Continuous output current: up to 2.1A (PVIN = 2.5V, VOUT = 3.3V) High effi...