3

LT1082

sn1082 1082fas

ELECTRICAL C

C

HARA TERISTICS

SYMBOL

PARAMETER

CONDITIONS

MIN

TYP

MAX

UNITS

Supply Current

3V

4.5

7.0

mA

Control Pin Threshold

Duty Cycle = 0

0.7

0.9

1.1

V

q

0.5

1.25

V

Normal/Flyback Threshold

0.58

0.67

0.8

V

on Feedback Pin

f

Switching Frequency

50

60

70

kHz

q

45

75

kHz

800

12

kHz

BV

Output Switch Breakdown Voltage

3V

q

100

115

V

Control Voltage to Switch

1.5

A/V

Current Transconductance

Flyback Reference Voltage

17

18.6

20.5

V

q

16

21.5

V

Change in Flyback Reference Voltage

60

3.5

4.6

6.5

V

Flyback Reference Voltage Line Regulation

0.01

0.03

%/V

150

300

500

µmho

Flyback Amplifier Source

q

15

32

70

µA

and Sink Current

q

30

50

90

µA

Output Switch “On” Resistance (Note 2)

q

0.8

1.2

Ω

Switch Current Limit

Duty Cycle = 20%

q

1.07

2.6

A

(LT1082C)

Duty Cycle

≤ 50%

q

1.0

2.6

A

Duty Cycle = 80% (Note 3)

q

0.8

2.4

A

Switch Current Limit

Duty Cycle = 20%

q

0.85

2.8

A

(LT1082I)

Duty Cycle

≤ 50%

q

0.8

2.8

A

Duty Cycle = 80% (Note 3)

q

0.65

2.6

A

Switch Current Limit

Duty Cycle = 20%

q

0.75

3.0

A

(LT1082M)

Duty Cycle

≤ 50%

q

0.7

3.0

A

Duty Cycle = 80% (Note 3)

q

0.6

2.8

A

Supply Current Increase

35

45

mA/A

During Switch-On Time

Maximum Switch Duty Cycle

85

92

97

%

Flyback Sense Delay Time

1.5

µs

Shutdown Mode Supply Current

3V

120

350

µA

Shutdown Mode

3V

70

150

250

mV

Threshold Voltage

q

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

guaranteed switch current decreases linearly.

specified.