SLVS010X january 1976 – june 2023 UA78L
PRODUCTION DATA
Refer to the PDF data sheet for device specific package drawings
The device has an internal current-limit circuit that protects the regulator during transient high-load current faults or shorting events. In a high-load current fault, the current limit scheme limits the output current to the current limit (ICL). ICL is listed in the Electrical Characteristics table.
The output voltage is not regulated when the device is in current limit. When a current-limit event occurs, the device begins to heat up because of the increase in power dissipation. When the device is in current limit, the pass transistor dissipates power [(VI – VO) × ICL]. For more information on current limits, see the Know Your Limits application note.
To achieve a safe operation across a wide range of Input voltage, the UA78L series also has a built-in protection mechanism with current limit. The protection mechanism decreases the current limit as input-to-output voltage increases and keeps the power transistor inside a safe operating region for all values of input-to-output voltage. This protection is designed to provide some output current at all values of input-to-output voltage limits defined in the Recommended Operating ConditionsRecommended Operating ConditionsRecommended Operating ConditionsRecommended Operating ConditionsRecommended Operating ConditionsRecommended Operating ConditionsRecommended Operating Conditions table. Figure 7-1 shows the behavior of the current limit variation.