LT3782A Datasheet, PDF (1/20 Pages) Linear Technology – 2-Phase Step-Up DC/DC Controller

FEATURES
n _{2-Phase Operation Reduces Required Input and}
Output Capacitance
n _{Programmable Switching Frequency:}
150kHz to 500kHz
n _{6V to 40V Input Range}
n _{10V Gate Drive with VCC ≥13V}
n _{High Current Gate Drive (4A)}
n _{Programmable Soft-Start and Current Limit}
n _{Programmable Slope Compensation for}
High Noise Immunity
n _{MOSFET Gate Signals with Programmable}
Falling Edge Delay for External Synchronous
Drivers
n _{Programmable Undervoltage Lockout}
n _{Programmable Duty Cycle Clamp (50% or Higher)}
n _{Thermally Enhanced 28-Lead TSSOP and 4mm × 5mm}
QFN Packages
APPLICATIONS
n _{Industrial Equipment}
n _{Telecom Infrastructure}
n _{Interleaved Isolated Power Supply}
LT3782A
2-Phase Step-Up
DC/DC Controller
DESCRIPTION
The LT^®3782A is a current mode 2-phase step-up DC/DC
converter controller. Its high switching frequency (up to
500kHz) and 2-phase operation reduce system filtering
capacitance and inductance requirements.
With 10V gate drive (V_CC ≥13V) and 4A peak drive current,
the LT3782A can drive most industrial grade high power
MOSFETs with high efficiency. For synchronous applica-
tions, the LT3782A provides synchronous gate signals
with programmable falling edge delay to avoid cross
conduction when using external MOSFET drivers. Other
features include programmable undervoltage lockout,
soft-start, current limit, duty cycle clamp (50% or higher)
and slope compensation. The LT3782A is identical to the
LT3782 except that the LT3782A has a tighter current sense
mismatch tolerance.
The LT3782A is available in thermally enhanced 28-lead
TSSOP and 4mm × 5mm QFN packages.
, LT, LTC and LTM are registered trademarks of Linear Technology Corporation.
All other trademarks are the property of their respective owners.
Protected by U.S. Patents, including 6144194.
TYPICAL APPLICATION
V_IN
10V TO 36V
10μF
×2
825k
274k
V_CC
1μF
RUN
50V 4A Boost Converter
20μH
GBIAS1
GBIAS2
GBIAS
BGATE1
20μH
2μF
D1
D2
10μF
×2
V_OUT
50V, 4A
+
220μF
100pF
LT3782A
V_EE1
59k
SLOPE
BGATE2
DELAY
80k
DCL
R_SET
V_EE2
SS
0.1μF
SENSE1⁺
V_C
13k
6.8nF
SENSE1^–
SENSE2⁺
SENSE2^–
GND
FB
0.004Ω
10Ω
10nF
10Ω
10nF
0.004Ω
475k
3782A TA01
24.9k
Efficiency and Power Loss
vs Load Current
97
18
EFFICIENCY
V_IN = 24V
95
15
V_IN = 12V
93
12
91
V_IN = 12V
9
89
V_IN = 24V ₆
POWER LOSS
87
3
85
0
0
1
2
3
4
5
I_OUT (A)
3782A TA01b
3782af
1