The ISL70321SEH and ISL73321SEH are radiation hardened and SEE mitigated power supply sequencers designed to drive Point-of-Load (POL) regulators with enable pins. Up to four power supplies can be fully sequenced by a single device or multiple devices can be easily cascaded to sequence an unlimited number of power supplies for dense RF applications. This power supply sequencer requires only two feedback resistors per power supply and a single resistor to set the rising and falling delay. The device features precision input comparators with an input threshold voltage of 600mV ±1.5% for the highest possible accuracy when monitoring the power supply voltages. The ISL70321SEH and ISL73321SEH are offered in an 18 Ld 10mm x 12mm CDFP package or die form and are fully specified across the military ambient temperature range of -55 °C to +125 °C. With minimal external component count, precision voltage monitoring, and SET mitigation, the ISL70321SEH and ISL73321SEH are the ideal choice to control many of today’s highly dense power systems in high-reliability applications.


  • Wide operating voltage range, 3V to 13.2V
  • Single resistor sets the rising and falling delay
  • Power-off POLs in reverse order or simultaneously
  • Precision voltage monitoring
  • 600mV ±1.5% threshold voltage over temperature and radiation
  • Full military temperature range operation
  • TA = -55 °C to +125 °C
  • TJ = -55 °C to +150 °C
  • Radiation hardness
  • High dose rate (HDR) (50-300rad(Si)/s): 100krad(Si) - ISL70321SEH only
  • Low dose rate (LDR) (0.01rad(Si)/s): 75krad(Si) ISL70321SEH and ISL73321SEH
  • SEE hardness (Review SEE report for details)
  • No SEB/SEL LETTH, VDD = 14.7V: 86MeV•cm2/mg
  • SET, SEFI free at LET 20MeV•cm2/mg
  • Electrically screened to DLA SMD 5962-17225




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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