4

LT1083/84/85 Fixed

PARAMETER

CONDITIONS

MIN

TYP

MAX

UNITS

Ripple Rejection

LT1085-3.3

q

60

72

dB

LT1085-3.6

q

60

72

dB

LT1083/4/5-5

q

60

68

dB

LT1083/4/5-12

q

54

60

dB

Temperature Stability

q

0.5

%

Long Term Stability

0.03

1.0

%

RMS Output Noise

10Hz =

≤ f ≤ 10kHz

0.003

%

Thermal Resistance

Control Circuitry/Power Transistor (See Applications Information)

Junctrion-to-Case

LT1083

K Package

0.6/1.6

°C/W

P Package

0.5/1.6

°C/W

LT1084

K Package

0.75/2.3

°C/W

P Package

0.65/2.3

°C/W

T Package

0.65/2.7

°C/W

LT1085

K Package

0.9/3.0

°C/W

T Package

0.7/3.0

°C/W

DD Package

0.7/3.0

°C/W

ELECTRICAL CHARACTERISTICS

input to output voltage. Note that the 60W power dissipation for the

LT1083 (45W for the LT1084 (K, P), 30W for the LT1084 (T), 30W for the

LT1085) is only achievable over a limited range of input to output voltage.

Note 4: Dropout voltage is specified over the full output current range of

the device. Test points and limits are shown on the Dropout Voltage curve.

Note 6: 1.7V

Note 7: Dropout voltage 1.7V maximum for LT1084 at – 55

Note 8: Full load current is not available at all input-output voltages.

See Notes 2,3,5.

OUTPUT CURRENT (A)

0

1

2

LT1083/4/5 FIXED G01

0

123456789

10

INDICATES GUARANTEED TEST POINT

–40°C

0°C

INPUT/OUTPUT DIFFERENTIAL (V)

0

8

10

12

15

25

LT1083/4/5 FIXED G02

6

4

510

20

30

35

2

0

25°C

–55°C

GUARANTEED

150°C

TEMPERATURE (°C)

–50

–0.20

–0.15

–0.10

–0.05

0

050

100

150

LT1083/4/5 FIXED G03

0.05

0.10

–25

25

75

125

∆I = 7.5A

LT1083 Dropout Voltage

LT1083 Load Regulation

LT1083 Short-Circuit Current

The q denotes the specifications which apply over the full operating

temperature range.

Note 1: See thermal regulation specifications for changes in output voltage

due to heating effects. Load and line regulation are measured at a constant

junction temperature by low duty cycle pulse testing.

Note 2: Line and load regulation are guaranteed up to the maximum power

dissipation (60W for the LT1083, 45W for the LT1084 (K, P), 30W for the

LT1084 (T) and 30W for the LT1085). Power dissipation is determined by

the input/output differential and the output current. Guaranteed maximum

power dissipation will not be available over the full input/output range.

curve is defined as the minimum value of current limit as a function of