All Output Voltage Versions

Electrical Characteristics (Note 16) (Continued)

Specifications with standard type face are for T

ture Range. Unless otherwise specified, V

and V

Symbol

Parameter

Conditions

Typ

LM2575-XXEP

Units

(Limits)

LM2575HV-XXEP

Limit

(Note 5)

DEVICE PARAMETERS

θ

JA

Thermal Resistance

T Package, Junction to Ambient (Note 11)

65

θ

JA

T Package, Junction to Ambient (Note 12)

45

˚C/W

θ

JC

T Package, Junction to Case

2

θ

JA

N Package, Junction to Ambient (Note 13)

85

θ

JA

M Package, Junction to Ambient (Note 13)

100

θ

JA

S Package, Junction to Ambient (Note 14)

37

ON /OFF CONTROL Test Circuit Figure 2

V

IH

ON /OFF Pin Logic

V

1.4

2.2/2.4

V(Min)

V

IL

Input Level

V

1.2

1.0/0.8

V(Max)

I

IH

ON /OFF Pin Input

ON /OFF Pin = 5V (OFF)

12

µA

Current

30

µA(Max)

I

IL

ON /OFF Pin = 0V (ON)

0µA

10

µA(Max)

Note 4: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for which the device is

intended to be functional, but do not guarantee specific performance limits. For guaranteed specifications and test conditions, see the Electrical Characteristics.

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.

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

LM2575EP is used as shown in the Figure 2 test circuit, system performance will be as shown in system parameters section of Electrical Characteristics.

Note 7: Output (pin 2) sourcing current. No diode, inductor or capacitor connected to output pin.

Note 8: Feedback (pin 4) removed from output and connected to 0V.

Note 9: Feedback (pin 4) removed from output and connected to +12V for the Adjustable, 3.3V, and 5V versions, and +25V for the 12V and 15V versions, to force

the output transistor OFF.

PC board with minimum copper area.

containing approximately 4 square inches of copper area surrounding the leads.

Note 13: Junction to ambient thermal resistance with approximately 1 square inch of pc board copper surrounding the leads. Additional copper area will lower

thermal resistance further. See thermal model in Switchers made Simple software.

Note 14: If the TO-263 package is used, the thermal resistance can be reduced by increasing the PC board copper area thermally connected to the package: Using

0.5 square inches of copper area,

Note 15: The oscillator frequency reduces to approximately 18 kHz in the event of an output short or an overload which causes the regulated output voltage to drop

approximately 40% from the nominal output voltage. This self protection feature lowers the average power dissipation of the IC by lowering the minimum duty cycle

from 5% down to approximately 2%.

Note 16: "Testing and other quality control techniques are used to the extent deemed necessary to ensure product performance over the specified temperature

range. Product may not necessarily be tested across the full temperature range and all parameters may not necessarily be tested. In the absence of specific

PARAMETRIC testing, product performance is assured by characterization and/or design."

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