LT1175



1175fe

Typical perForMance characTerisTics

Typical Current Limit

Characteristics

Guaranteed Current Limit

Output Voltage Temperature Drift

Minimum Input-to-Output Voltage

Minimum Input-to-Output Voltage

SENSE Bias Current

(Adjustable Part)

elecTrical characTerisTics

Note 8: Thermal regulation is a change in the output voltage caused by

die temperature gradients, so it is proportional to chip power dissipation.

Temperature gradients reach final value in less than 100ms. Output voltage

changes after 100ms are due to absolute die temperature changes and

reference voltage temperature coefficient.

Note 9: The lower limit of 0.8V is guaranteed to keep the regulator in

shutdown. The upper limit of 2.5V is guaranteed to keep the regulator

active. Either polarity may be used, referenced to GND pin.

Note 10: Load and line regulation are measured on a pulse basis with

pulse width of 20ms or less to keep chip temperature constant. DC

regulation will be affected by thermal regulation (Note 8) and chip

temperature changes. Load regulation specification also holds for currents

Note 11: Current limit is reduced for input-to-output voltage above 12V.

See the graph in Typical Performance Characteristics for guaranteed limits

above 12V.

Note 12: Operating at very large input-to-output differential voltages

(>15V) with load currents less than 5mA requires an output capacitor with

an ESR greater than 1Ω to prevent low level output oscillations.

INPUT-TO-OUTPUT DIFFERENTIAL VOLTAGE (V)

0

1.0

0.8

0.6

0.4

0.2

0

20

1175 G01

5

10

15

25

CURRENT LIMIT CHANGES ONLY SLIGHTLY

WITH TEMPERATURE SO CURVES ARE

REPRESENTATIVE OF ALL TEMPERATURES

INPUT-TO-OUTPUT DIFFERENTIAL VOLTAGE (V)

0

0.6

0.5

0.4

0.3

0.2

0.1

0

5

10

15

20

1175 G02

25

CURVES REPRE-

SENT MINIMUM

GUARANTEED

LIMITS AT ALL

TEMPERATURES

JUNCTION TEMPERATURE (°C)

–50

5.05

5.00

4.95

3.84

3.80

3.76

0

50

75

1175 G03

–25

25

100 125

OUTPUT

FIXED 5V PART

FEEDBACK VOLTAGE

ADJUSTABLE PART

OUTPUT CURRENT (A)

0

1.0

0.8

0.6

0.4

0.2

0

0.2

0.4

0.5

1175 G04

0.1

0.3

0.6

0.7

UNTIL OUTPUT

VOLTAGE

DROPS 1%

OPEN

OUTPUT CURRENT (A)

0

1.0

0.8

0.6

0.4

0.2

0

0.2

0.4

0.5

1175 G05

0.1

0.3

0.6

0.7

VOLTAGE DROPS 1%.

TEMPERATURE (°C)

–50

100

80

60

40

20

0

0

50

75

1175 G06

–25

25

100 125