5

ELECTRICAL CHARACTERISTICS: All Output Voltage Versions

(Specifications with standard type face are for T = 25°C, and those with boldface type apply over full Operating Temperature Range. Unless otherwise

J

specified, V = 12V for the 3.3V, 5.0V and ADJ version, V = 25V for 12V version. and V = 30V for 15V version. I

= 500 mA)

IN

IN

IN

LOAD

Parameter

Conditions

Symbol

Min

Typ

Max

Unit

Oscillator Frequency

Saturation Voltage

Max Duty Cycle (ON)

Output Leakage Current

Quiescent Current

Standby Quiescent Current

Thermal Resistance

Feedback Bias Current

Current Limit

Logic Input Level

ON/OFF Pin

ON/OFF Pin Input Current

V

= 5V (Adjustable Version Only)

OUT

(Note 11)

I

= 1A (Notes 4)

OUT

(Note 5)

(Note 4, 11)

(Notes 6, 7)

Output = 0 V

Output = -1V

(Note 6)

ON/OFF Pin = 5V (OFF)

TO-220 Package, Junction to Ambient (Note 8)

TO-220 Package, Junction to Ambient (Note 8)

TO-220,TO-263, Package, Junction to Case

TO-252 Package, Junction to Case

TO-263 Package, Junction to Ambient (Note 10)

V

=0V

OUT

V

= Nominal Output Voltage

OUT

I

FB

F

O

V

SAT

TDC

I

OL

I

Q

I

STBY

V

IH

V

IL

V

IH

I

IL

-

47 / 42

-

-

-

-

-

-

-

-

-

-

-

-

50

52

0.9

98

2.2

-

7.5

5

50

1.4

1.2

12

0

65

45

2

6

37

-

-

-

-

100 / 500

58 / 63

1.2 / 1.4

-

2

30

10

200

30

10

kHz

V

%

A

mA

mA

mA

°C/W

V

V

mA

mA

nA

93

I

CL

1.7 / 1.3

3.0 / 3.2

ON/OFF Pin = 5V (OFF)

ON/OFF Pin = 0V (ON)

2.2 / 2.4

-

-

1.0 / 0.8

Note 1: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indic

ate conditions for which the device is intended to be functional, but do not guarantee specific performance limits.

Guaranteed specifications and Test conditions are shown in Electrical Characteristics.

Note 2: All limits guaranteed at 25°C (standard type face) and over full operating temperature range (bold type face).

All 25°C limits are 100% production tested. All limits over full operating temperature range are guaranteed via

correlation using standard Statistics Quality Control methods.

Note 3: External components such as the catch diode, inductor, input and output capacitors can affect switching regulator

system performance. When the

as shown in system parameters section of Electrical Characteristics.

Note 4: Output pin sourcing current. No diode, inductor or capacitor connected to output.

Note 5: Feedback pin removed from output and connected to 0V.

Note 6: Feedback pin 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.

Note 7: V

= 40V

IN

Note 8: Junction to ambient thermal resistance (no external heat sink) for the 5 lead TO-220 package mounted vertically,

with ½ inch leads in a socket, or on a PC board with minimum copper area.

Note 9: Junction to ambient thermal resistance (no external heat sink) for the 5 lead TO-220 package mounted vertically,

with ¼ inch leads soldered to a PC board containing approximately 4 square inches of copper area surrounding

the leads.

Note 10: 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, q

is 50°C//W, with 1 square inch

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of copper area, q

is 37°C/W, and with 1.6 or more square inches of copper area, q is 32°C/W.

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JA

Note 11: The oscillator frequency reduces to approximately 11 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

5% down to approximately 2%.

LM2575 By lowering the minimum duty cycle from

LM2575 is used as show in the Figure 2 test circuit, system performance will be

LM2575 1.0A Step - Down Voltage Switching Regulators