LT3504
3
3504fa
For more information www.linear.com/LT3504
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 LT3504EUF 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
LT3504IUF is guaranteed over the full –40°C to 125°C operating junction
temperature range.
The l denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. V
IN
= 12V unless otherwise noted.
Note 3: Current flows into pin.
Note 4: Quiescent current (V
IN
) is measured at V
EN/UVLO
= 1V
Note 5: Current flows out of pin.
Note 6: Current limit is guaranteed by design and/or correlation to static
test. Slope compensation reduces current limit at higher duty cycles.
Note 7: 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.
SYMBOL CONDITIONS MIN TYP MAX UNITS
RUN/SS Pin Source Current V
RUN/SS
= 0V 1.3 µA
RUN/SS Pin Threshold for Switching V
FB
= 0V 50 100 mV
Feedback Voltage
l
790
784
800
800
810
816
mV
mV
FB Pin Current V
FB
= Measured V
FB
(Note 5)
l
15 150 nA
Reference Line Regulation V
IN
= 5V to 40V –0.015 %/V
SKY Pin Current I
SW
= 1A 27 40 mA
SKY Voltage above V
IN
Voltage V
SKY
– V
IN
4.85 V
Switching Frequency R
T
= 6.34k
R
T
= 18.2k
R
T
= 100k
l
l
l
1.8
0.85
200
2.1
1
250
2.4
1.15
300
MHz
MHz
kHz
Switching Phase R
T
= 18.2k 150 180 210 Deg
SYNC Threshold Voltage 1.25 V
SYNC Input Frequency 0.35 2.2 MHz
Switch Current Limit (SW1,2,3,4) (Note 6) 1.45 1.75 2.1 A
Switch V
CESAT
(SW1,2,3,4) I
SW
= 1A 400 mV
Switch Leakage Current (SW1,2,3,4) 0.1 2 µA
Catch Diode Current Limit (SW1,2,3,4) FB = 0V
FB = 0.7V
0.75
1.0
1.15
1.45
1.33
1.67
A
A
Switch Current Limit (SW5) (Note 6) 220 320 mA
Switch V
CESAT
(SW5) I
SW
= 200mA 230 mV
Switch Leakage Current (SW5) 0.1 2 µA
Boost Diode Current Limit (SW5) V
IN
= 5V 350 450 mA
PG Threshold Offset V
FB
Rising 65 90 125 mV
PG Hysteresis V
FB
Rising – V
FB
Falling 35 mV
PG Voltage Output Low I
PG
= 250µA 180 300 mV
PG Pin Leakage V
PG
= 2V 0.01 1 µA
