3

LT1072

1072fc

SYMBOL

PARAMETER

CONDITlONS

MIN

TYP

MAX

UNITS

Reference Voltage

Measured at Feedback Pin

1.224

1.244

1.264

V

●

1.214

1.244

1.274

V

Feedback Input Current

350

750

nA

●

1100

nA

gm

Error Amplifier

3000

4400

6000

µmho

Transconductance

●

2400

7000

µmho

Error Amplifier Source or

150

200

350

µA

Sink Current

●

120

400

µA

Error Amplifier Clamp

1.8

2.3

V

Voltage

0.25

0.38

0.52

V

Reference Voltage Line

●

0.03

%/V

Regulation

%/V

Error Amplifier Voltage Gain

500

800

V/V

Minimum Input Voltage

●

2.6

3.0

V

Supply Current

6

9

mA

Control Pin Threshold

Duty Cycle = 0

0.8

0.9

1.08

V

●

0.6

1.25

V

Normal/Flyback Threshold on Feedback Pin

0.4

0.45

0.54

V

Flyback Reference Voltage

16.3

17.6

V

●

14

18

V

Change in Flyback Reference Voltage

4.5

6.8

8.5

V

Flyback Reference Voltage

0.01

0.03

%/V

Line Regulation

%/V

Flyback Amplifier Transconductance (gm)

150

300

650

µmho

Flyback Amplifier Source

Source

●

15

32

70

µA

and Sink Current

●

25

40

70

µA

BV

Output Switch Breakdown

LT1072

●

65

90

V

Voltage

LT1072HV

●

75

90

V

LT1072S8

●

60

80

V

Output Switch ON Resistance (Note 2)

●

0.6

1

Ω

Control Voltage to Switch Current Transconductance

2

A/V

Switch Current Limit

Duty Cycle = 50%

●

1.25

3

A

Duty Cycle = 50%

●

1.25

3.5

A

Duty Cycle = 80% (Note 3)

●

1

2.5

A

Supply Current Increase

25

35

mA/A

During Switch ON Time

f

Switching Frequency

35

40

45

kHz

●

33

47

kHz

DC (max)

Maximum Switch Duty Cycle

90

92

97

%

Flyback Sense Delay Time

1.5

µs

Shutdown Mode

100

250

µA

Supply Current

Shutdown Mode

100

150

250

mV

Threshold Voltage

●

50

300

mV

Note 1: Absolute Maximum Ratings are those values beyond which the life

of a device may be impaired.

Note 3: For duty cycles (DC) between 50% and 80%, minimum

ELECTRICAL CHARACTERISTICS