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3. Thermal protection

XB1117 series has thermal protection which limits junction temperature to 150

℃. However, device functionally is only

guaranteed to a maximum junction temperature of + 125

℃. The power dissipation and junction temperature for the XB1117

series are given by;

NOTE

4. Current limit protection

XB1117 series is protected against overload conditions. Current protection is triggered at 1.5A (TYP.).

5. Thermal consideration

The XB1117 series contain thermal limiting circuitry designed to protect itself from over-temperature conditions.

Even for

normal load conditions, maximum junction temperature ratings must not be exceeded.

As mentioned in thermal protection

section, we need to consider all sources of thermal resistance between junction and ambient.

It includes junction-to-case,

case-to-heat-sink interface and heat sink thermal resistance itself.

Junction-to-case thermal resistance is specified from the IC junction to the bottom of the case directly below the die. Proper

mounting is required to ensure the best possible thermal flow from this area of the package to the heat sink. The case of all

devices in this product series is electrically connected to the output. Therefore, if the case of the device is not electrically

isolated, a thermally conductive spacer is recommended.

■APPLICATION CIRCUITS

●Adjustable Output Voltage

■OPERATIONAL EXPLANATION (Continued)