LT1175 Ver la hoja de datos (PDF) - Linear Technology

Número de pieza

componentes Descripción

Lista de partido

LT1175

500mA Negative Low Dropout Micropower Regulator

Linear Technology 

LT1175

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

up to the specified current limit when ILIM2 or ILIM4 are left open.

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.

Typical Performance Characteristics

Typical Current Limit

Characteristics

1.0

CURRENT LIMIT CHANGES ONLY SLIGHTLY

WITH TEMPERATURE SO CURVES ARE

REPRESENTATIVE OF ALL TEMPERATURES

0.8

ILIM2, ILIM4 TIED TO VIN

0.6

ILIM4 TIED TO VIN

0.4

ILIM2 TIED TO VIN

0.2

ILIM2, ILIM4 OPEN

0

0

5

10

15

20

25

INPUT-TO-OUTPUT DIFFERENTIAL VOLTAGE (V)

1175 G01

Minimum Input-to-Output Voltage

1.0

TJ = 25°C

VIN REDUCED

0.8 UNTIL OUTPUT

VOLTAGE

DROPS 1%

0.6

ILIM2, ILIM4

OPEN

ILIM2 TIED

TO VIN

0.4

ILIM4 TIED

TO VIN

0.2

ILIM2, ILIM4

TIED TO VIN

0

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7

OUTPUT CURRENT (A)

1175 G04

Guaranteed Current Limit

0.6

ILIM2, ILIM4 TIED TO VIN

0.5

0.4 ILIM4 TIED TO VIN

CURVES REPRE-

SENT MINIMUM

GUARANTEED

LIMITS AT ALL

TEMPERATURES

0.3 ILIM2 TIED TO VIN

0.2

ILIM2, ILIM4 OPEN

0.1

0

0

5

10

15

20

25

INPUT-TO-OUTPUT DIFFERENTIAL VOLTAGE (V)

1175 G02

Minimum Input-to-Output Voltage

1.0

VIN REDUCED UNTIL OUTPUT

VOLTAGE DROPS 1%.

0.8 ILIM2, ILIM4 TIED TO VIN

0.6

TJ = 125°C

0.4

TJ = 25°C

0.2

TJ = –55°C

0

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7

OUTPUT CURRENT (A)

1175 G05

Output Voltage Temperature Drift

5.05

OUTPUT

FIXED 5V PART

5.00

4.95

3.84

FEEDBACK VOLTAGE

3.80 ADJUSTABLE PART

3.76

–50

–25 0 25 50 75 100 125

JUNCTION TEMPERATURE (°C)

1175 G03

SENSE Bias Current

(Adjustable Part)

100

80

60

40

20

0

–50 –25

0 25 50 75

TEMPERATURE (°C)

100 125

1175 G06

1175fe



Share Link: