LM2575TV 参数 Datasheet PDF下载

1A, 52kHz, Step-Down Switching Regulator

ELECTRICAL CHARACTERISTICS

/ Device Parameters

LM2575

(Unless otherwise specified, Vin = 12 V for the 3.3 V, 5.0 V, and Adjustable version, Vin = 25 V for the 12

V version, and Vin = 30 V for the 15 V version. ILoad = 500 mA. For typical values TJ = 25°C, for min/max

values TJ is the operating junction temperature range that applies [Note 2], unless otherwise noted.)

Characteristics

All Output Voltage Versions

Feedback Bias Current (Vout=5.0V [Adjustable Version Only])

Symbol

Min

TYP

Max

Unit

T

J

=25℃

T

J

= -40 to +125℃

Oscillator Frequency [Note 3]

T

J

=25℃

T

J

= 0 to +125℃

T

J

= -40 to +125℃

Saturation Voltage (Iout=1A [note 4])

T

J

=25℃

T

J

= -40 to +125℃

Max Duty Cycle ("0") [Note 5]

Current Limit (Peak Current [Note 3 and 4])

T

J

=25℃

T

J

= -40 to +125℃

Output Leakage Current [Note 6 and 7], T

J

=25℃

Output = 0V

Output = -1.0V

Quiescent Current [Note 6]

T

J

=25℃

T

J

= -40 to +125℃

Standby Quiescent Current (ON/OFF Pin = 5.0V ("off"))

T

J

=25℃

T

J

= -40 to +125℃

ON/OFF Pin Logic Input Level (Test circuit Figure 15)

Vout=0V

T

J

=25℃

T

J

= -40 to +125℃

Vout=Nominal Output Voltage

T

J

=25℃

T

J

= -40 to +125℃

ON/OFF Pin Input Current (Test Circuit Figure 15)

ON/OFF Pin = 5.0V (Regulator OFF), TJ=25℃

ON/OFF Pin = 0V (Regulator ON), TJ=25℃

I

b

-

-

-

47

42

-

-

94

4.2

3.5

-

-

-

-

-

-

25

-

52

-

-

1.2

-

98

5.8

-

0.8

6

5

-

80

-

100

200

-

58

63

1.4

1.7

-

6.9

7.5

50

30

9

11

200

400

nA

Fosc

kHz

Vsat

DC

I

CL

V

%

A

I

L

mA

I

Q

mA

I

STBY

㎂

V

IH

2.2

2.4

-

-

-

-

1.4

-

1.2

-

15

0

-

-

1

0.8

30

5.0

V

V

IL

V

I

IH

I

IL

㎂

3. 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 dissipation of the IC by lowering the minimum duty cycle

from 5% down to approximately 2%.

4. Output (Pin 2) sourcing current. No diode, inductor or capacitor connected to output pin.

5. Feedback (Pin 4) removed from output and connected to 0 V.

6. Feedback (Pin 4) removed from output and connected to +12 V for the Adjustable, 3.3 V, and 5.0V ersions,

and +25 V for the 12 V and15 V versions, to force the output transistor “off”.

7. Vin = 40 V.

−

4

−

HTC