How to Confirm Fail-Safe Output Status Using a Datasheet

To confirm the fail-safe output status using the Infineon ISOFACE™ datasheet, the core method is to consult the official English datasheet for the specific model. Use the PDF search function to locate keywords such as "fail-safe output," "default output state," or "output state during undervoltage," and check their explicit definitions. Verify the default state corresponding to the model suffix in the "Ordering Information" table. The 4DIRx4xxH/HA series explicitly supports high/low selectable models.

I. Obtaining the Correct Datasheet

Visit the Infineon website product page. Search for the target model in your browser, such as 4DIR0401HA, and go to its official product page on Infineon.com.

Download the latest English datasheet. Locate the file of type "Data Sheet" in the "Documents" area, prioritizing PDF documents with EN language and the latest version number.

Example Link: ISOFACE™ 4DIRx4xxH Datasheet

Note: The Chinese translation may be outdated or contain errors. Engineering design should adhere to the original English version.

II. Locating Key Information in the Manual

After opening the PDF, follow these steps:

1. Use the search function to find keywords:

fail-safe output

default output state

output state during undervoltage

input unpowered

2. Identify Typical Descriptions

In the ISOFACE™ 4DIRx4xxH series manuals, common descriptions include:

"The device features a fail-safe output that ensures a defined high (or low) state at the output when the input side supply is removed."

This indicates that when the input side is de-energized, the output will maintain a predefined high or low level.

3. Check Model Code Description

The "Ordering Information" table usually lists the functional differences corresponding to different suffixes:

4DIR0401H → Fail-safe high

4DIR0400H → Fail-safe low

Some model suffixes "H" and "HA" may represent different default states; each must be confirmed in the manual.

III. Confirm Model Selection Based on Application Scenarios

Practical Tip: In hot runner or new energy systems, it is recommended to print or archive key pages of the selected model's datasheet as a basis for FMEA analysis and functional safety audits.