System Board 6634

MAXREFDES1123: 80V/5mA, High-Voltage, Compact Boost Power Supply Using MAX1523

 Download Full Reference Design

Input Type VIN (MIN)
Isolated/Non-Isolated Topology
DC 4.5 5.5 0.0055 Single 80 0.44 Non-Isolated Boost

The MAXREFDES1123 is a compact boost power-supply design for high-voltage applications with low currentrequirements where extremely low cost and small sizeare top priorities. This design provides an 80V output and up to 5mA of load current. This power supply is designed specifically to provide a simple application circuit at high voltage and to minimize the size and number of external components, making it ideal for low-cost consumer electronics applications.

This design is centered around the MAX1523 simple SOT23 boost controller. The design is tested at 5V nominal voltage input. The output voltage is within 1% error margin.

Key Features

  • Small Size (134mm2)
  • 80V/5mA Output
  • Low Quiescent Current (25μA typ)
  • Pin-Selectable Maximum Duty Factor
  • Internal Soft-Start and Short-Circuit Protection
  • Discontinuous Conduction Mode (DCM)
MAXREFDES1123 Hardware Enlarge+

This board is not available for purchase.

Designed, Built, Tested

This document describes the hardware shown in Figure 1. It provides a detailed systematic technical guide for designing a boost controller using the MAX1523 for high voltage, low current, and small size. Refer to the MAX1523 IC data sheet for device operation details. The power supply has been built and tested, details of which follow later in this document.

Design Resources


Simple SOT23 Boost Controllers

  • Simple, Flexible Application Circuit
  • 2-Cell NiMH or Alkaline Operation (MAX1524)
  • Low Quiescent Current (25µA typ)