LT3724EFE Datasheet, PDF (1/26 Pages) Linear Technology – High Voltage, Current Mode Switching Regulator Controller

FEATURES
n _{Wide Input Range: 4V to 60V}
n _{Output Voltages up to 36V (Step-Down)}
n _{Burst Mode}^® _{Operation: <100µA Supply Current}
n _{10µA Shutdown Supply Current}
n _{±1.3% Reference Accuracy}
n _{200kHz Fixed Frequency}
n _{Drives N-Channel MOSFET}
n _{Programmable Soft-Start}
n _{Programmable Undervoltage Lockout}
n _{Internal High Voltage Regulator for Gate Drive}
n _{Thermal Shutdown}
n _{Current Limit Unaffected by Duty Cycle}
n _{16-Pin Thermally Enhanced TSSOP Package}
APPLICATIONS
n _{Industrial Power Distribution}
n _{12V and 42V Automotive and Heavy Equipment}
n _{High Voltage Single Board Systems}
n _{Distributed Power Systems}
n _Avionics
n _{Telecom Power}
LT3724
High Voltage, Current Mode
Switching Regulator Controller
DESCRIPTION
The LT^®3724 is a DC/DC controller used for medium power,
low part count, low cost, high efficiency supplies. It of-
fers a wide 4V-60V input range (7.5V minimum startup
voltage) and can implement step-down, step-up, inverting
and SEPIC topologies.
The LT3724 includes Burst Mode operation, which re-
duces quiescent current below 100µA and maintains
high efficiency at light loads. An internal high voltage bias
regulator allows for simple biasing and can be back driven
to increase efficiency.
Additional features include fixed frequency current mode
control for fast line and load transient response; a gate driver
capable of driving large N-channel MOSFETs; a precision
undervoltage lockout function; 10µA shutdown current;
short-circuit protection; and a programmable soft-start
function that directly controls output voltage slew rates at
startup which limits inrush current, minimizes overshoot
and facilitates supply sequencing.
L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and
Burst Mode is a trademark of Linear Technology Corporation. All other trademarks are the property
of their respective owners. Protected by U.S. Patents including 5731694, 6498466, 6611131.
TYPICAL APPLICATION
V_IN
30V TO
60V
C_IN
68µF
680pF
40.2k
120pF
4.99k
High Voltage Step-Down Regulator
1M
68.1k
200k
93.1k
V_IN
BOOST
TG
LT3724
SHDN
SW
C_SS
Burst_EN V_CC
V_FB
V_C
1000pF
SGND
PGND
SENSE⁺
SENSE^–
0.22µF
10Ω
Si7852
SS3H9
47µH
0.025Ω
1µF
V_OUT
24V
+
75W
C_OUT
330µF
3724 TA01a
Efficiency and Power Loss
vs Load Current
95
12
90
10
EFFICIENCY
85
8
80
6
75
70
65
0.1
4
LOSS
2
V_IN = 48V
0
1
10
LOAD CURRENT (A)
3724 TA01b
3724fd
1