The Intersil ISL43120, ISL43121 and ISL43122 devices are precision, bidirectional, dual analog SPST switches designed to operate from a single +2. 7V to +12V supply. Targeted applications include battery powered equipment that benefit from the devices’ low power consumption (5μW), low leakage currents (100pA max) and fast switching speeds (tON = 28ns, tOFF = 20ns). Cell phones, for example, often face ASIC functionality limitations. The number of analog input or GPIO pins may be limited and digital geometries are not well suited to analog switch performance. This family of parts may be used to “mux-in” additional functionality while reducing ASIC design risk. Some of the smallest packages are available, alleviating board space limitations and making Intersil’s newest line of low-voltage switches an ideal solution. The ISL43120, ISL43121, ISL43122 are dual single-pole/single-throw (SPST) devices. The ISL43120 has two normally open (NO) switches; the ISL43121 has two normally closed (NC) switches; the ISL43122 has one NO and one NC switch and can be used as an SPDT.


  • Fully specified at 12V, 5V, and 3.3V supplies for 10% tolerances
  • ON-resistance (rON): 19Ω
  • rON matching between channels: <1Ω
  • Low charge injection: 5pC (Max)
  • Single supply operation: +2.7V to +12V
  • Low power consumption (PD): <5μW
  • Low leakage current: 10nA
  • Fast switching action
  • tON: 28ns
  • tOFF: 20ns
  • Guaranteed break-before-make (ISL43122 only)
  • Minimum 2000V ESD protection per method 3015.7
  • TTL, CMOS compatible
  • Available in SOT-23 packaging
  • Pb-free (RoHS Compliant)



  • Battery-powered, handheld and portable equipment Cellular/mobile phones Pagers Laptops, notebooks, palmtops
  • Communications systems Radios, ADSL Modems PBX, PABX
  • Test and measurement equipment Ultrasound Computerized Tomography (CT) Scanner Magnetic Resonance Image (MRI) Position Emission Tomography (PET) Scanner Electrocardiograph
  • Heads-up displays
  • Audio and video switching
  • Various circuits +3V/+5V DACs and ADCs Sample and hold circuits Digital filters Operational amplifier gain switching networks High frequency analog switching High speed multiplexing Integrator reset circuits

Design & Development