LT1121-3.3 Linear Technology, LT1121-3.3 Datasheet - Page 3

• Manufacturer Part Number: LT1121-3.3
• Description: Micropower Low Dropout Regulators with Shutdown
• Manufacturer: Linear Technology

ELECTRICAL C
The
range.
Note 1: The Shutdown pin input voltage rating is required for a low
impedance source. Internal protection devices connected to the shutdown
pin will turn on and clamp the pin to approximately 7V or – 0.6V. This
range allows the use of 5V logic devices to drive the pin directly. For high
impedance sources or logic running on supply voltages greater than 5.5V,
the maximum current driven into the shutdown pin must be limited to less
than 20mA.
Note 2: For junction temperatures greater than 110 C, a minimum load of
1mA is recommended. For T
may increase by 1%.
Note 3: Operating conditions are limited by maximum junction
temperature. The regulated output voltage specification will not apply for
all possible combinations of input voltage and output current. When
operating at maximum input voltage, the output current range must be
limited. When operating at maximum output current the input voltage
range must be limited.
PARAMETER
Load Regulation
Dropout Voltage
(Note 5)
Ground Pin Current
(Note 6)
Adjust Pin Bias Current (Notes 4, 7)
Shutdown Threshold
Shutdown Pin Current (Note 8)
Quiescent Current in Shutdown (Note 9)
Ripple Rejection
Current Limit
Input Reverse Leakage Current
Reverse Output Current (Note 10)
denotes specifications which apply over the operating temperature
J
HARA TERISTICS
> 110 C and I
C
OUT
V
V
LT1121-3.3
LT1121-5
LT1121 (Note 4)
I
I
I
LOAD
I
I
I
I
I
I
I
I
I
I
T
V
V
V
V
f
V
LT1121-3.3
LT1121-5
LT1121 (Note 4)
LOAD
LOAD
LOAD
LOAD
LOAD
LOAD
LOAD
LOAD
LOAD
LOAD
LOAD
LOAD
LOAD
RIPPLE
CONDITIONS
J
OUT
OUT
SHDN
IN
IN
IN
IN
= 25 C
= 6V, V
– V
– V
= –20V, V
< 1mA, output voltage
= 50mA
= Off to On
= On to Off
= 1mA, T
= 1mA
= 50mA, T
= 100mA, T
= 100mA
= 150mA, T
= 150mA
= 0mA
= 1mA
= 10mA
= 50mA
= 100mA
= 150mA
= 0V
OUT
OUT
= 120Hz, I
SHDN
= 1V (Avg), V
= 7V, T
OUT
J
J
= 25 C
= 0V
J
J
LOAD
= 25 C
= 0V
J
= 25 C
= 25 C
= 25 C
V
V
V
I
I
I
I
I
I
OUT
OUT
OUT
= 0.1A
LOAD
LOAD
LOAD
LOAD
LOAD
LOAD
RIPPLE
= 3.3V, V
= 5V, V
= 3.8V, V
= 1mA to 150mA, T
= 1mA to 150mA
= 1mA to 150mA, T
= 1mA to 150mA
= 1mA to 150mA, T
= 1mA to 150mA
= 0.5V
IN
IN
IN
Note 4: The LT1121 (adjustable version) is tested and specified with the
adjust pin connected to the output pin.
Note 5: Dropout voltage is the minimum input/output voltage required to
maintain regulation at the specified output current. In dropout the output
voltage will be equal to: (V
Note 6: Ground pin current is tested with V
current source load. This means that the device is tested while operating
in its dropout region. This is the worst case ground pin current. The
ground pin current will decrease slightly at higher input voltages.
Note 7: Adjust pin bias current flows into the adjust pin.
Note 8: Shutdown pin current at V
Note 9: Quiescent current in shutdown is equal to the sum total of the
shutdown pin current (6 A) and the ground pin current (9 A).
Note 10: Reverse output current is tested with the input pin grounded and
the output pin forced to the rated output voltage. This current flows into
the output pin and out of the ground pin.
= 0V
P-P
= 0V
= 0V
,
LT1121/LT1121-3.3/LT1121-5
J
J
J
= 25 C
= 25 C
= 25 C
IN
– V
DROPOUT
SHDN
MIN
0.25
50
= 0V flows out of the shutdown pin.
).
IN
= V
0.13
0.30
0.37
0.42
TYP
– 12
– 20
– 17
– 28
– 12
– 18
350
150
200
1.5
4.0
7.0
1.2
0.75
30
90
15
58
16
16
16
6
OUT
(nominal) and a
MAX
0.16
0.25
0.35
0.50
0.45
0.60
0.55
0.70
14.0
– 20
– 30
– 30
– 45
– 20
– 30
120
500
300
500
2.5
7.0
2.8
1.0
50
10
22
25
25
25
UNITS
3
mV
mV
mV
mV
mV
mV
mA
mA
mA
mA
mA
nA
dB
V
V
V
V
V
V
V
V
A
A
A
V
V
A
A
A
A
A