LT3682
3
3682f
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 the device
reliability and lifetime.
Note 2: Absolute Maximum Voltage at V
IN
and RUN/SS pins is 60V for
nonrepetitive 1 second transients, and 36V for continuous operation.
Note 3: The LT3682E is guaranteed to meet performance specifi cations from
0°C to 125°C junction temperature. Specifi cations over the −40°C to 125°C
operating junction temperature range are assured by design, characterization
and correlation with statistical process controls. The LT3682I is guaranteed
over the full −40°C to 125°C operating junction temperature range.
The l denotes specifi cations which apply over the full operating temperature
range, otherwise specifi cations are at T
A
= 25°C, V
IN
= 10V, V
RUN
/SS = 10V, V
BD
= 3.3V unless otherwise noted. (Note 3)
PARAMETER CONDITIONS MIN TYP MAX UNITS
V
C
Source Current 50 µA
V
C
Sink Current 50 µA
V
C
Pin to Switch Current Gain 1.25 A/V
V
C
Switching Threshold 0.5 0.6 0.7 V
V
C
Clamp Voltage 2V
Switching Frequency R
RT
= 8.06k
R
RT
= 29.4k
R
RT
= 158k
1.98
0.9
225
2.2
1
250
2.42
1.1
275
MHz
MHz
kHz
Minimum Switch Off-Time
l
130 210 ns
Switch Current Limit (Note 7) SYNC = 0V
SYNC = 3.3V or Clocked
1.45
1.18
1.7
1.4
2
1.66
A
A
Switch V
CESAT
I
SW
= 1A 460 mV
DA Pin Current to Stop OSC 1.25 1.6 1.95 A
Switch Leakage Current V
SW
= 0V, V
IN
= 60V 0.01 1 µA
Boost Schottky Diode Voltage Drop I
BSD
= 50mA 720 850 mV
Boost Schottky Diode Reverse Leakage V
SW
= 10V, V
BD
= 0 0.1 1 µA
Minimum Boost Voltage (Note 5)
l
1.7 2.5 V
BOOST Pin Current I
SW
= 0.5A 10.5 17.5 mA
RUN/SS Pin Current V
RUN/SS
= 10V 12 20 µA
RUN/SS Input Voltage High 2.5 V
RUN/SS Input Voltage Low 0.2 V
PG Leakage Current V
PG
= 5V 0.1 1 µA
PG Sink Current V
PG
= 0.4V
l
100 1000 µA
PG Threshold as % of V
FB
Measured at FB pin. FB Pin Voltage Rising 88% 90% 92% V
PG Threshold Hysteresis Measured at FB Pin 12 mV
SYNC Threshold Voltage 300 550 800 mV
SYNC Input Frequency 0.3 2.2 MHz
Note 4: Bias current fl ows out of the FB pin.
Note 5: This is the minimum voltage across the boost capacitor needed to
guarantee full saturation of the switch.
Note 6: This IC includes over-temperature protection that is intended
to protect the device during momentary overload conditions. Junction
temperature will exceed the maximum operating junction temperature
when over-temperature protection is active. Continuous operation above
the specifi ed maximum operating junction temperature may impair device
reliability.
Note 7: Current limit guaranteed by design and/or correlation to static test.
Slope compensation reduces current limit at higher duty cycles.
