4
LT1764A Series
1764afb
Current Limit V
IN
= 7V, V
OUT
= 0V 4 A
E Grade: LT1764A; LT1764A-1.5; ● 3.1 A
V
IN
= 2.7V, ∆V
OUT
= – 0.1V
MP Grade: LT1764A ● 3.1 A
V
IN
= 2.8V, ∆V
OUT
= – 0.1V
Input Reverse Leakage Current V
IN
= –20V, V
OUT
= 0V ● 1mA
Reverse Output Current (Note 10) LT1764A-1.5 V
OUT
= 1.5V, V
IN
< 1.5V 600 1200 µA
LT1764A-1.8 V
OUT
= 1.8V, V
IN
< 1.8V 600 1200 µA
LT1764A-2.5 V
OUT
= 2.5V, V
IN
< 2.5V 600 1200 µA
LT1764A-3.3 V
OUT
= 3.3V, V
IN
< 3.3V 600 1200 µA
LT1764A (Note 3) V
OUT
= 1.21V, V
IN
< 1.21V 300 600 µA
Note 1:
Stresses beyond those listed under Absolute Maximum Ratings
may cause permanent damage to the device. Exposure to any Absolute
Maximum Rating condition for extended periods may affect device
reliability and lifetime.
Note 2: The LT1764A regulators are tested and specified under pulse load
conditions such that T
J
≈ T
A
. The LT1764A (E grade) 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. The
LT1764A (MP grade) is 100% tested and guaranteed over the –55°C to
125°C temperature range.
Note 3: The LT1764A (adjustable version) is tested and specified for these
conditions with the ADJ pin connected to the OUT pin.
Note 4. 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 max-
imum input voltage, the output current range must be limited. When operat-
ing at maximum output current, the input voltage range must be limited.
Note 5: To satisfy requirements for minimum input voltage, the LT1764A
(adjustable version) is tested and specified for these conditions with an
external resistor divider (two 4.12k resistors) for an output voltage of
2.42V. The external resistor divider will add a 300µA DC load on the output.
Note 6: 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 7: GND pin current is tested with V
IN
= V
OUT(NOMINAL)
+ 1V or V
IN
=
2.7V (E grade) or V
IN
= 2.8V (MP grade), whichever is greater, and a current
source load. The GND pin current will decrease at higher input voltages.
Note 8: ADJ pin bias current flows into the ADJ pin.
Note 9: SHDN pin current flows into the SHDN pin.
Note 10: 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 11. For the LT1764A, LT1764A-1.5 and LT1764A-1.8 dropout voltage
will be limited by the minimum input voltage specification under some
output voltage/load conditions.
Note 12. All combinations of absolute maximum input voltage and
absolute maximum output voltage cannot be achieved. The absolute
maximum differential from input to output is ±20V. For example, with
V
IN
= 20V, V
OUT
cannot be pulled below ground.
ELECTRICAL CHARACTERISTICS
PARAMETER CONDITIONS MIN TYP MAX UNITS
The ● denotes specifications which apply over the full operating temperature range, otherwise specifications are T
A
= 25°C. (Note 2)
TYPICAL PERFOR A CE CHARACTERISTICS
UW
Typical Dropout Voltage
OUTPUT CURRENT (A)
0
0
DROPOUT VOLTAGE (mV)
100
200
300
400
600
0.5
1.0 1.5 2.0
1764 G01
2.5 3.0
500
T
J
= 125°C
T
J
= 25°C
Guaranteed Dropout Voltage
OUTPUT CURRENT (A)
0
700
600
500
400
300
200
100
0
1.5 2.5
1764 G02
0.5 1.0
2.0 3.0
GUARANTEED DROPOUT VOLTAGE (mV)
= TEST POINTS
T
J
≤ 125°C
T
J
≤ 25°C
TEMPERATURE (°C)
–50
DROPOUT VOLTAGE (mV)
400
500
600
25 75
1764 G03
300
200
–25 0
50 100 125
100
0
I
L
= 3A
I
L
= 1.5A
I
L
= 0.5A
I
L
= 100mA
I
L
= 1mA
Dropout Voltage
