All Output Voltage Versions

Note 5: All limits guaranteed at room temperature (standard type face) and at temperature extremes (bold type face). All room temperature limits are 100%

production tested. All limits at temperature extremes are guaranteed via correlation using standard Statistical Quality Control (SQC) methods. All limits are used to

calculate Average Outgoing Quality Level (AOQL).

Note 6: External components such as the catch diode, inductor, input and output capacitors can affect switching regulator system performance. When the

LM2597/LM2597HV is used as shown in the

Note 7: The switching frequency is reduced when the second stage current limit is activated. The amount of reduction is determined by the severity of current

overload.

Note 8: No diode, inductor or capacitor connected to output pin.

Note 9: Feedback pin removed from output and connected to 0V to force the output transistor switch ON.

Note 10: Feedback pin removed from output and connected to 12V for the 3.3V, 5V, and the ADJ. version, and 15V for the 12V version, to force the output transistor

switch OFF.

Note 12: Junction to ambient thermal resistance with approximately 1 square inch of printed circuit board copper surrounding the leads. Additional copper area will

Typical Performance Characteristics

Normalized

Output Voltage

DS012440-2

Line Regulation

DS012440-3

Efficiency

DS012440-4

Switch Saturation

Voltage

DS012440-5

Switch Current Limit

DS012440-6

Dropout Voltage

DS012440-7

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