The ISL9021A is a single LDO, which provides high performance, low input voltage and high PSRR. It delivers guaranteed continuous 250mA load current and is stable with 1µF to 4. 7µF of output capacitance (±30%) with an ESR range of 5mΩ to 400mΩ. The input voltage range for the ISL9021A is between 1. 5V to 5. 5V and the output voltage comes in many fixed voltage options with ±1. 8% accuracy over-temperature, line and load ranges. The ISL9021A has typical PSRR of 75dB @ 10kHz and 50dB @ 1MHz. The reverse current protection feature prevents current from flowing back to the power source when the output voltage is pulled higher than the input. The ISL9021A is offered in tiny 4-bump 0. 975mmx1. 155mm WLCSP and 1. 6mmx1. 6mm 6 Ld µTDFN packages.


  • High Performance LDO with 250mA Guaranteed Continuous Output Current
  • Input Voltage Range: 1.5V to 5.5V
  • Output Voltage Range: 1.2V to 3.3V
  • High PSRR: 75dB @ 10kHz, 50dB @ 1MHz
  • Low Quiescent Current: 35µA
  • Dropout Voltage: <150mV @ 250mA
  • Stable with 1µF to 4.7µF Output Capacitance (±30%) with an ESR range of 5mΩ to 400mΩ
  • ±1.8% Output Accuracy Over-Temperature/Load/Line
  • Soft-start Limits Input Current Surge During Enable
  • Current Limit and Overheat Protection
  • -40°C to +85°C Operating Temperature Range
  • Available in 0.975mmx1.155mm 4-bump WLCSP Package and 1.6mmx1.6mm 6 Ld µTDFN
  • Pb-free (RoHS compliant)



  • PDAs, Cell Phones and Smart Phones
  • Portable Instruments, MP3 Players
  • Handheld Devices including Medical Handhelds


Document title Document type Type Date Date
PDF 625 KB Datasheet
PDF 509 KB Application Note
PDF 397 KB Application Note
PDF 1.55 MB Manual - Development Tools
PDF 414 KB Product Advisory
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Software title Software type Type Date Date
ZIP 1.80 MB PCB Design Files
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