LT1963 Series
ELECTRICAL CHARACTERISTICS
Note 1:
Absolute Maximum Ratings are those values beyond which the life
of a device may be impaired.
Note 2:
Absolute maximum input to output differential voltage can not be
achieved with all combinations of rated IN pin and OUT pin voltages. With
the IN pin at 20V, the OUT pin may not be pulled below 0V. The total
measured voltage from IN to OUT can not exceed
±20V.
Note 3:
The LT1963 regulators are tested and specified under pulse load
conditions such that T
J
≈
T
A
. The LT1963 is 100% tested at
T
A
= 25°C. Performance at – 40°C and 125°C is assured by design,
characterization and correlation with statistical process controls.
Note 4:
The LT1963 (adjustable version) is tested and specified for these
conditions with the ADJ pin connected to the OUT pin.
Note 5:
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.
Note 6:
To satisfy requirements for minimum input voltage, the LT1963
(adjustable version) is tested and specified for these conditions with an
external resistor divider (two 4.12k resistors) for an output voltage of
2.4V. The external resistor divider will add a 300µA DC load on the output.
Note 7:
Dropout voltage is the minimum input to output voltage differential
needed to maintain regulation at a specified output current. In dropout, the
output voltage will be equal to: V
IN
– V
DROPOUT
.
Note 8:
GND pin current is tested with V
IN
= V
OUT(NOMINAL)
+ 1V and a
current source load. The GND pin current will decrease at higher input
voltages.
Note 9:
ADJ pin bias current flows into the ADJ pin.
Note 10:
SHDN pin current flows into the SHDN pin.
Note 11:
Reverse output current is tested with the IN pin grounded and the
OUT pin forced to the rated output voltage. This current flows into the OUT
pin and out the GND pin.
Note 12.
For the LT1963, LT1963-1.5 and LT1963-1.8 dropout voltage will
be limited by the minimum input voltage specification under some output
voltage/load conditions.
Note 13.
For the ST package, the input reverse leakage current increases
due to the additional reverse leakage current for the SHDN pin, which is
tied internally to the IN pin.
TYPICAL PERFOR A CE CHARACTERISTICS
Typical Dropout Voltage
500
450
400
DROPOUT VOLTAGE (mV)
600
GUARANTEED DROPOUT VOLTAGE (mV)
350
300
250
200
150
100
50
0
0
0.2
DROPOUT VOLTAGE (mV)
T
J
= 125°C
T
J
= 25°C
0.4 0.6 0.8 1.0 1.2
OUTPUT CURRENT (A)
Quiescent Current
1.4
1.2
QUIESCENT CURRENT (mA)
LT1963-1.8/-2.5/-3.3
OUTPUT VOLTAGE (V)
1.0
0.8
0.6
0.4
0.2
V
IN
= 6V
R
L
=
∞,
I
L
= 0
V
SHDN
= V
IN
50
25
75
0
TEMPERATURE (°C)
100
125
LT1963
1.81
1.80
1.79
1.78
1.77
1.76
–50 –25
0
25
50
75
100
125
OUTPUT VOLTAGE (V)
0
– 50 – 25
4
U W
1.4
1963 • G01
1963
G04
Guaranteed Dropout Voltage
TEST POINTS
Dropout Voltage
500
450
500
T
J
≤
125°C
400
T
J
≤
25°C
300
200
100
0
400
350
300
250
200
150
100
50
I
L
= 100mA
I
L
= 1mA
–25
50
0
75
25
TEMPERATURE (°C)
100
125
I
L
= 0.5A
I
L
= 1.5A
1.6
0
0.2
0.4 0.6 0.8 1.0 1.2
OUTPUT CURRENT (A)
1.4
1.6
0
–50
1963 • G02
1963 G03
LT1963-1.8 Output Voltage
1.84
I
L
= 1mA
1.83
1.82
2.56
2.54
2.52
2.50
2.48
2.46
2.44
2.58
LT1963-2.5 Output Voltage
I
L
= 1mA
2.42
–50 –25
0
25
50
75
100
125
TEMPERATURE (°C)
1963 G05
TEMPERATURE (°C)
1963 G06
1963fa
LINEAR [ LINEAR INTEGRATED SYSTEMS ]
