LT1129/LT1129-3.3/LT1129-5
U W
TYPICAL PERFOR A CE CHARACTERISTICS
Shutdown Pin Input Current
Shutdown Pin Current
Adjust Pin Bias Current
400
350
300
250
200
150
100
50
10
9
8
7
6
5
4
3
2
1
0
25
20
V
SHDN
= 0V
V
= V
= 3.75V
OUT
ADJ
15
10
5
0
0
50
75 100 125
–50
–25
0
25
50
75 100 125
–50
0
25
–25
0
1
2
3
4
5
6
7
8
9
TEMPERATURE (°C)
TEMPERATURE (°C)
SHUTDOWN PIN VOLTAGE (V)
1129 G28
1129 G25
1129 G24
Reverse Output Current
Current Limit
Current Limit
30
25
20
15
10
5
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0
V
V
V
V
= 0V
= V
V
= 0V
IN
OUT
= 5V (LT1129-5)
OUT
OUT
OUT
SENSE
SENSE
= V
= V
= 3.3V (LT1129-3.3)
= 3.75V (LT1129)
ADJ
V
V
= 7V
OUT
IN
= 0V
0
–50
0
25
50
75 100 125
0
2
3
4
5
6
7
50
–25
1
–50
0
25
75 100 125
–25
TEMPERATURE (°C)
INPUT VOLTAGE (V)
TEMPERATURE (°C)
1129 G29
1129 G07
1129 G08
Reverse Output Current
Ripple Rejection
Ripple Rejection
70
68
66
64
62
60
58
56
100
90
80
70
60
50
40
30
20
10
0
100
90
80
70
60
50
40
30
20
10
0
I
= 500mA
T
= 25°C, V = 0V
IN
OUT
IN
(V – V
IN
)AVG = 1V
P-P
J
V
OUT
= 0.5V
V
= 6V + 50mV
RIPPLE
= V
RMS
OUT
SENSE
V
RIPPLE
= 0.7A
(LT1129-3.3/LT1129-5)
V
CURRENT FLOWS
INTO DEVICE
I
L
= V
(LT1129)
OUT
ADJ
C
= 47µF
OUT
SOLID
TANTALUM
LT1129
LT1129-3.3
C
= 3.3µF
SOLID
TANTALUM
OUT
LT1129-5
–50
0
25
50
75 100 125
10
100
1k
FREQUENCY (Hz)
10k
100k
1M
–25
0
2
4
6
8
10
1
3
5
7
9
TEMPERATURE (°C)
OUTPUT VOLTAGE (V)
1129 G01
1129 G03
1129 G30
6
Linear [ Linear ]
