ISL9105 is a 600mA, 1. 6MHz step-down regulator that is ideal for powering low-voltage microprocessors in handheld devices such as PDAs and cellular phones. It is optimized for generating low output voltages down to 0. 8V. The supply voltage range is from 2. 7V to 5. 5V, allowing for the use of a single Li+ cell, three NiMH cells or a regulated 5V input. It has a guaranteed minimum output current of 600mA. 1. 6MHz pulse-width modulation (PWM) switching frequency allows for use of small external components. It has flexible operation mode selection of forced PWM mode and low IQ mode with typical 25µA quiescent current for highest light load efficiency to maximize battery life. The ISL9105 includes a pair of low ON-resistance P-Channel and N-Channel internal MOSFETs to maximize efficiency and minimize external component count. 100% duty-cycle operation allows less than 200mV dropout voltage at 600mA output current. The ISL9105 offers a typical 216ms Power-On-Reset (POR) timer at power-up. The timer output can be reset by RSI. When shutdown, ISL9105 discharges the output capacitor. Other features include internal digital soft-start, enable for power sequence, overcurrent protection, and thermal shutdown. The ISL9105 is offered in a 2mmx3mm 8 Ld DFN package with 1mm maximum height. The complete converter occupies less than 1cm2 area.


  • High Efficiency Synchronous Buck Regulator with up to 95% Efficiency
  • Selectable Forced PWM Mode and SKIP Mode
  • 25µA Quiescent Supply Current in SKIP Mode
  • 2.7V to 5.5V Supply Voltage
  • 216ms POR Timer
  • 3% Output Accuracy Over Temperature/Line/Load
  • 600mA Guaranteed Output Current
  • Less than 1µA Logic Controlled Shutdown Current
  • 100% Maximum Duty Cycle for Lowest Dropout
  • Discharge Output Capacitor when Shutdown
  • Internal Loop Compensation
  • Internal Digital Soft-Start
  • Peak Current Limit Protection, Short Circuit Protection
  • Over-Temperature Protection
  • Enable
  • Small 8 Ld 2mmx3mm DFN
  • Pb-free (RoHS Compliant)


  • Single Li-Ion Battery-Powered Equipment
  • DSP Core Power
  • PDAs and Palmtops

Product Options

Part Number Part Status Pkg. Type Carrier Type MOQ Buy Sample
Active DFN Reel 6000

Documentation & Downloads

Title Other Languages Type Format File Size Date
Datasheets & Errata
ISL9105 Datasheet Datasheet PDF 922 KB
User Guides & Manuals
ISL9105EVAL1Z User Guide Manual PDF 807 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
AN1684: Nonideality of Ground Application Note PDF 397 KB
AN1681: Grounding Techniques Application Note PDF 509 KB
AN9210: A New Pspice Subcircuit For The Power MOSFET Featuring Global Temperature Options Application Note PDF 650 KB
AN9209: A Spice-2 Subcircuit Representation For Power MOSFETs Using Empirical Methods Application Note PDF 387 KB
AN7244: Understanding Power MOSFETs Application Note PDF 349 KB

Boards & Kits

Part Number Title Type Company
ISL9105EVAL1Z High-Efficiency Synchronous Buck Regulator Evaluation Board Evaluation Renesas
ISL9106EVAL1Z High-Efficiency Synchronous Buck Regulator Evaluation Board Evaluation Renesas
ISL9107EVAL1Z High-Efficiency Synchronous Buck Regulator Evaluation Board Evaluation Renesas
ISL9108EVAL1Z High-Efficiency Synchronous Buck Regulator Evaluation Board Evaluation Renesas