ISL91110 and ISL91110IR are high-current buck-boost switching regulators for systems using new battery chemistries. They use Intersil’s 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. ISL91110 and ISL91110IR are capable of delivering at least 2A continuous output current (VOUT = 3.3V) over 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. Their fully synchronous low ON-resistance 4-switch architecture and a low quiescent current of only 35μA optimize efficiency under all load conditions.

ISL91110 and ISL91110IR support standalone 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 1.0V or as high as 5.2V are supported. ISL91110 and ISL91110IR require only a single inductor and very few external components. Power supply solution size is minimized by its 2. 5MHz switching frequency, allowing small size external components.

The ISL91110 is available in a 25-bump, 0.4mm pitch WLCSP (2.33mm x 2.07mm) and the ISL91110IR is available in a 4mm x 4mm, 20 Ld TQFN package.


  • 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
  • Output current: up to 2A (PVIN = 3.4V, VOUT = 5V) (ISL91110IR only)
  • Output current: up to 2A (PVIN = 2.5V, VOUT = 3.3V) (ISL91110 and ISL91110IR)
  • Burst current: up to 3A (PVIN = 3V, VOUT = 3.3V, tON < 600μs, t = 4.6ms)
  • High efficiency: up to 96%
  • High efficiency: up to 95% (ISL91110IR only)
  • 35μA quiescent current maximizes light- load efficiency
  • 2.5MHz switching frequency minimizes external component size
  • Fully protected for short-circuit, over-temperature, and undervoltage
  • Small 2.33mmx2.07mm WLCSP (ISL91110 only)
  • Small 4mmx4mm 20 Ld TQFN package (ISL91110IR only)


  • Brownout free system voltage for smartphones and tablet PCs
  • Wireless communication devices
  • 2G/3G/4G RF power amplifiers


Title language Type Format File Size Date
Datasheets & Errata
star ISL91110IR Datasheet Datasheet PDF 778 KB
ISL91110 Datasheet Datasheet PDF 857 KB
Application Notes & White Papers
Five Easy Steps to Create a Multi-Load Power Solution White Paper PDF 846 KB
AN9208: High Frequency Power Converters Application Note PDF 592 KB
AN1681: Grounding Techniques Application Note PDF 509 KB
AN1684: Nonideality of Ground Application Note PDF 397 KB
PCN15062A - Alternate assembly and test facility for Intersil Product ISL91110IIAZ* Product Change Notice PDF 89 KB
ISL91110 iSim:PE Model Schematic SXSCH 211 KB

select_allSoftware & Tool Pages

Title Type Description Company
iSim:PE Offline Simulation Tool Simulator iSim Personal Edition (iSim:PE) speeds the design cycle and reduces risk early in any project, identifying parts that can be used in current as well as next-generation designs. Renesas

memoryBoards & Kits

Part Number Title Type Company
ISL91110IIA-EVZ High-Current Buck-Boost Switching Regulator Evaluation Board Evaluation Renesas
ISL91110IIN-EVZ High-Current Buck-Boost Switching Regulator Evaluation Board Evaluation Renesas
ISL91110II2A-EVZ High-Current Buck-Boost Switching Regulator Evaluation Board Evaluation Renesas