LT3505 LINER [Linear Technology], LT3505 Datasheet - Page 4

• Manufacturer Part Number: LT3505
• Description: Monolithic Dual Tracking 3A Step-Down Switching
• Manufacturer: LINER [Linear Technology]

LT3501
elecTrical characTerisTics
Note 4: An internal power-on reset (POR) latch is set on the positive
transition of the SHDN pin through its threshold. The output of the latch
activates current sources on each SS pin which typically sink 1.5mA,
discharging the SS capacitor. The latch is reset when both SS pins are
driven below the soft-start POR threshold or the SHDN pin is taken below
its threshold.
Note 5: To enhance dropout operation, the output switch will be turned off
for the minimum off-time only when the voltage across the boost capacitor
drops below the minimum boost for 100% duty cycle threshold.
Note 6: The IND to V
Typical perForMance characTerisTics
4
0.816
0.811
0.801
0.796
0.786
0.806
0.791
16
14
12
10
8
6
4
2
0
–50
–50
Feedback Voltage vs Temperature
Shutdown Quiescent Current
vs Temperature
–25
–25
V
VIN1
0
0
TEMPERATURE (°C)
TEMPERATURE (°C)
OUT
25
25
maximum current is defined as the value of
50
50
75
75
V
VIN2
100
100
3501 G02
3501 G05
125
125
1.01
0.95
1.05
1.03
0.99
0.97
4.0
3.8
3.6
3.4
3.2
3.0
2.8
2.6
2.4
2.2
2.0
–50 –25
–50
R
Soft-Start Source Current
vs Temperature
T
/SYNC Voltage vs Temperature
–25
0
0
TEMPERATURE (°C)
TEMPERATURE (°C)
25
25
current flowing from the IND pin to the V
latch when the V
Note 7: This is the minimum voltage across the boost capacitor needed to
guarantee full saturation of the internal power switch.
Note 8: This IC includes overtemperature protection that is intended
to protect the device during momentary overload conditions. Junction
temperature will exceed 125°C when overtemperature protection is active.
Continuous operation above the specified maximum operating junction
temperature may impair device reliability.
50
50
75
75
100
100
3501 G03
3501 G06
C
pin is at its high clamp.
125
125
3.0
2.5
1.5
1.0
0.5
5.0
4.8
4.6
4.4
4.2
4.0
3.8
3.6
3.4
3.2
3.0
2.0
0
–50
–50
Shutdown Threshold and Minimum
Input Voltage vs Temperature
IND to V
vs Temperature
V
OUT
–25
–25
= 5V
OUT
OUT
0
0
pin which resets the switch
TEMPERATURE (°C)
TEMPERATURE (°C)
MINIMUM INPUT
Maximum Current
THRESHOLD
SHUTDOWN
VOLTAGE
VOLTAGE
25
25
V
OUT
50
50
= 0V
75
75
100
100
3501 G04
3501 G07
3501fd
125
125