Diodes Incorporated

APX803/APX803D (Not Recommended for new design)

Contact Sales

Log in or register to manage email notifications about changes to datasheets or PCNs for this part.


The APX803/D is used for microprocessor (μP) supervisory circuits to monitor the power supplies in μP and digital systems. They provide excellent circuit reliability and low cost by eliminating external components and adjustments when used with +5V, +3.3V, +3.0V powered circuits. These circuits perform a single function: they assert a reset signal on power up and whenever the VCC supply voltage declines below a preset threshold, keeping it asserted for a fixed period of time a VCC has risen above the preset threshold. For the APX803D this period is at least 1ms while for other APX803 variants it is at least 140ms. Reset thresholds suitable for operation with a variety of supply voltages are available. The APX803 have an open collector active low RESET output which enables simple interface to µP with bi-directional reset inputs and also to wire-or several devices together enabling multple rails to be monitored via one µP input. The reset comparator is designed to ignore fast transients on VCC, and the outputs are guaranteed to be in the correct logic state for VCC down to 1V. Low supply current makes the APX803 ideal for use in portable equipment. The APX803 is available in two pin out variants of the 3-pin SOT23 and SOT23R packages.


  • Precision Monitor of 2.5V/3.0V/3.3V/5.0V power supply voltage
  • Full specified over temperature
  • Available in four output configuration
  • Open drain Active low reset APX803
  • Power-on reset generator with fixed delay time 200ms
  • SOT23 Green mold compound (No Br, Sb)


  • Computers
  • Controllers
  • Intelligent Instruments
  • Critical ?P and ?C Power Monitoring
  • Portable/Battery-Powered Equipment

Product Specifications

Product Parameters

Related Content

Quality Documentation

Technical Documents

Recommended Soldering Techniques