Features and Benefits

  • Simple Power-Supply Transformer Driver Design for Isolated RS-485/RS-232 Data-Interface Applications
    • Single 5V or 3.3V Supply
    • Low-Current Shutdown Mode: 0.4µA
    • Pin-Selectable Frequency: 350kHz or 200kHz
  • 8-Pin DIP, SO, and µMAX® Packages Take Minimal Board Space

Product Details

The MAX253 monolithic oscillator/power-driver is specifically designed to provide isolated power for an isolated RS-485 or RS-232 data interface. The device drives a center-tapped transformer primary from a 5V or 3.3V DC power supply. The secondary can be wound to provide any isolated voltage needed at power levels up to 1W.

The MAX253 consists of a CMOS oscillator driving a pair of N-channel power switches. The oscillator runs at double the output frequency, driving a toggle flip-flop to ensure 50% duty cycle to each of the switches. Internal delays are arranged to ensure break-before-make action between the two switches.

The SD pin puts the entire device into a low-power shutdown state, disabling both the power switches and oscillator.


  • Bridge Ground Differentials
  • High Noise-Immunity Communications Interface
  • Isolated and/or High-Voltage Power Supplies
  • Isolated RS-485/RS-232 Power Supply
  • Medical Equipment
  • Process Control
  • Transformer Driver

Product Lifecycle icon-recommended Production

At least one model within this product family is in production and available for purchase. The product is appropriate for new designs but newer alternatives may exist.

Design Resources

ADI has always placed the highest emphasis on delivering products that meet the maximum levels of quality and reliability. We achieve this by incorporating quality and reliability checks in every scope of product and process design, and in the manufacturing process as well.  "Zero defects" for shipped products is always our goal.

PCN-PDN Information

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Buy Now Pricing

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List Pricing

(*)The 1Ku list pricing shown is for BUDGETARY USE ONLY, shown in United States dollars (FOB USA per unit for the stated volume), and is subject to change. International prices may differ due to local duties, taxes, fees and exchange rates. For volume-specific price or delivery quotes, please contact your local Analog Devices, Inc. authorized distributor. Pricing displayed for Evaluation Boards and Kits is based on 1-piece pricing.


Lead Times

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