The ISL8023 is a highly efficient, monolithic, synchronous step-down DC/DC converter that can deliver 3A of continuous output current from a 2.7V to 5.5V input supply. The device uses current mode control architecture to deliver very low-duty cycle operation at high frequency with fast transient response and excellent loop stability. It has an adjustable frequency from 500kHz to 4MHz with the default at 1MHz (ISL8023/24).

The ISL8023 and ISL8024 integrate a very low On-resistance P-Channel (45mΩ) high side FET and N-Channel (19mΩ) low side FET to maximize efficiency and minimize external component count. The 100% duty-cycle operation allows less than 200mV dropout voltage at 4A output current. The operation frequency of the pulse-width modulator (PWM) is adjustable from 500kHz to 4MHz. The default switching frequency of 1MHz is set by connecting the FS pin high, which allows for the use of small external components.

The ISL8023, ISL8024 can be configured for discontinuous or forced continuous operation at light load. Forced continuous operation reduces noise and RF interference while discontinuous mode provides higher efficiency by reducing switching losses at light loads.

Fault protection is provided by internal hiccup mode current limiting during short circuit and overcurrent conditions. Other protection, such as overvoltage and over-temperature are also integrated into the device. A power-good output voltage monitor indicates when the output is in regulation.

The ISL8023, ISL8024 offer a 1ms Power-Good (PG) timer at power-up. When in shutdown, ISL8023, ISL8024 discharges the output capacitor through an internal soft-stop switch. Other features include internal fixed or adjustable soft-start and internal/external compensation. The ISL8023 and ISL8024 are offered in a space saving 16 Ld 3x3 Pb-free QFN package with an exposed pad for improved thermal performance and 1mm maximum height. The complete converter occupies less than 0.22 in2 area.

Various fixed output voltages are available upon request. See the datasheet for more details.


  • 2.7V to 5.5V input voltage range
  • Very low on-resistance FET's - P-Channel 45mΩ and N-Channel 19mΩ typical values
  • High efficiency synchronous buck regulator with up to 95% efficiency
  • 0.8% reference accuracy over-temperature/load/line
  • Complete BOM with as few as 3 external parts
  • Start-up with pre-biased output
  • Internal soft-start - 1ms or adjustable
  • Soft-stop output discharge during disabled
  • Adjustable frequency from 500kHz to 4MHz - default at 1MHz (8023/24), 2MHz (8023A/24A)
  • External synchronization up to 4MHz
  • Over-temperature, Overcurrent, Overvoltage and negative overcurrent protection
  • Tiny 3x3 QFN package




  • DC/DC POL modules
  • μC/µP, FPGA and DSP power
  • Plug-in DC/DC modules for routers and switchers
  • Portable instruments
  • Test and measurement systems
  • Li-ion battery powered devices


Design & Development

Software & Tools

Software & Tools

Software title
Software type
iSim:PE Offline Simulation Tool
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.
Simulator Renesas
1 item

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