Datasheet

LT3686
3
3686fc
PARAMETER CONDITIONS MIN TYP MAX UNITS
Quiescent Current at Shutdown V
EN/UVLO
< 0.4V
V
EN/UVLO
= 1V
0.1
10
1
15
µA
µA
Quiescent Current Not Switching, MODE ≤ 0.4V
Not Switching, MODE ≥ 0.8V
1.1
1.2
1.3
1.4
mA
mA
Internal Undervoltage Lockout 3.4 3.6 V
Overvoltage Lockout
l
37 38 39 V
Feedback Voltage
l
0.790
0.785
0.8
0.8
0.810
0.815
V
V
Feedback Voltage Line Regulation
V
IN
= 3.6V ↔ 37V
0.0012 %/V
FB Pin Bias Current 20 100 nA
Switching Frequency I
DA
< 1.2A
R
T
= 15.4kΩ
R
T
= 100kΩ
R
T
= 267kΩ
0.3
1.9 2.1
670
300
2.5
2.3
MHz
MHz
kHz
kHz
Minimum On Time 100 110 ns
Minimum Off Time 150 200 ns
Switch V
CESAT
I
SW
= 1.2A 680 mV
Switch Current Limit (Note 3)
l
1.9
1.85
2.3
2.3
2.6
2.65
A
A
Switch Active Current SW = 10V (Note 4)
SW = 0V (Note 5)
400
20
600
30
µA
µA
BOOST Pin Current I
SW
= 1.2A 20 mA
Minimum Boost Voltage Above Switch I
SW
= 1.2A 2.2 2.4 V
Max BD Pin Active Load Current MODE > 0.8V, BD < 5.2V 30 40 mA
BD Pin Active Load Disable Threshold
l
5.2 6.5 V
DA Pin Current to Stop OSC
l
1.2 1.7 A
MODE High
l
0.8 V
MODE Low
l
0.4 V
MODE Pin Bias Current 0.1 µA
SS Threshold 0.9 V
SS Source Current V
SS
= 1V 1.3 2 2.7 µA
EN/UVLO Bias Current V
EN/UVLO
= 10V
V
EN/UVLO
= 0V
40
1
µA
µA
EN/UVLO Threshold to Turn Off
l
1.22 1.27 1.32 V
EN/UVLO Hysteresis Current 1.8 2.4 3 µA
Boost Diode Forward Drop I
BD
to I
BOOST
= 200mA 0.85 V
The l denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. V
IN
= 10V, V
EN/UVLO
≥ 1.32V.
electricAl chArActeristics
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 LT3686E is guaranteed to meet performance specifications
from 0°C to 125°C junction temperature. Specifications over the –40°C
to 125°C operating junction temperature range are assured by design,
characterization and correlation with statistical process controls. The
LT3686I is guaranteed over the full –40°C to 125°C operating junction
temperature range. The LT3686H is guaranteed over the full –40°C to
150°C operating junction temperature range.
Note 3: Current limit guaranteed by design and/or correlation to static test.
Slope compensation reduces current limit at higher duty cycle.
Note 4: Current flows into pin.
Note 5: Current flows out of pin.
Note 6: This IC includes overtemperature protection that is intended
to protect the device during momentary overload conditions. Junction
temperature will exceed the maximum operating junction temperature
when overtemperature protection is active. Continuous operation above
the specified maximum operating junction temperature may impair device
reliability. See High Temperature Consideration section. Also see Operation
section.