LT1175
TYPICAL PERFORMANCE CHARACTERISTICS
Typical Current Limit
Characteristics
1.0
CURRENT LIMIT CHANGES ONLY SLIGHTLY
WITH TEMPERATURE SO CURVES ARE
REPRESENTATIVE OF ALL TEMPERATURES
I
LIM2
, I
LIM
TIED TO V
IN
0.6
I
LIM2
, I
LIM
TIED TO V
IN
0.5
0.4
0.3
0.2
I
LIM2
, I
LIM4
OPEN
0.1
0
3.80
I
LIM4
TIED TO V
IN
CURVES REPRE-
SENT MINIMUM
GUARANTEED
LIMITS AT ALL
TEMPERATURES
VOLTAGE (V)
0.8
CURRENT (A)
CURRENT (A)
0.6
I
LIM4
TIED TO V
IN
0.4
I
LIM2
TIED TO V
IN
0.2
I
LIM2
, I
LIM4
OPEN
0
5
15
0
20
25
10
INPUT-TO-OUTPUT DIFFERENTIAL VOLTAGE (V)
1175 G01
Minimum Input-to-Output Voltage
1.0
INPUT-TO-OUTPUT VOLTAGE (V)
INPUT-TO-OUTPUT VOLTAGE (V)
0.8
T
J
= 25°C
V
IN
REDUCED
UNTIL OUTPUT
VOLTAGE
DROPS 1%
I
LIM2
, I
LIM4
OPEN
0.6
0.6
T
J
= 125°C
0.4
T
J
= 25°C
0.2
T
J
= –55°C
CURRENT (nA)
I
LIM2
TIED
TO V
IN
0.4
I
LIM4
TIED
TO V
IN
I
LIM2
, I
LIM4
TIED TO V
IN
0
0.1
0.2 0.3 0.4
0.5
OUTPUT CURRENT (A)
0.6
0.7
0.2
0
Shutdown Input Current
25
2.5
20
INPUT CURRENT (µA)
15
T
J
= 25°C
T
J
= 125°C
10
T
J
= –55°C
5
1.5
NEGATIVE THRESHOLD
1.0
PIN CURRENT (µA)
THRESHOLD (V)
0
0
5
15
10
INPUT VOLTAGE (V)
20
25
1175 G07
4
U W
1175 G04
Guaranteed Current Limit
5.05
Output Voltage Temperature Drift
OUTPUT
FIXED 5V PART
5.00
4.95
I
LIM2
TIED TO V
IN
3.84
FEEDBACK VOLTAGE
ADJUSTABLE PART
5
10
15
20
25
0
INPUT-TO-OUTPUT DIFFERENTIAL VOLTAGE (V)
1175 G02
3.76
50
0
75 100
25
–50 –25
JUNCTION TEMPERATURE (°C)
125
1175 G03
Minimum Input-to-Output Voltage
1.0
V
IN
REDUCED UNTIL OUTPUT
VOLTAGE DROPS 1%.
I
LIM2
, I
LIM4
TIED TO V
IN
100
SENSE Bias Current
(Adjustable Part)
0.8
80
60
40
20
0
0
0.1
0.2 0.3 0.4
0.5
OUTPUT CURRENT (A)
0.6
0.7
0
–50 –25
50
0
75
25
TEMPERATURE (°C)
100
125
1175 G05
1175 G06
Shutdown Thresholds
15
POSITIVE THRESHOLD
SHDN Pin Characteristics
V
IN
= 25V
CHARACTERISTICS DO NOT
CHANGE SIGNIFICANTLY WITH
TEMPERATURE, SO A SINGLE
CURVE IS SHOWN. POSITIVE
CURRENT FLOWS INTO
SHDN PIN
2.0
10
5
0
IF SHDN PIN IS NEGATIVE WITH
RESPECT TO INPUT VOLTAGE AND
INPUT VOLTAGE IS LESS THAN 15V,
NEGATIVE BREAKOVER POINT WILL
BE ABOUT 8V BELOW –V
IN
0.5
DEVICE IS OFF
BELOW THRESHOLD
0
–50 –25
25
50
0
75
TEMPERATURE (°C)
100
125
–5
–10
–25 –20 –15 –10 –5 0 5 10 15 20 25
SHUTDOWN TO GROUND VOLTAGE (V)
1175 G09
1175 G08
LINER [ LINEAR TECHNOLOGY ]
