LT3782_15 Datasheet, PDF (1/20 Pages) Linear Technology – 2-Phase Step-UP DC/DC Controller

NOT RECOMMENDED FOR NEW DESIGNS
Contact Linear Technology for Potential Replacement
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}
LT3782
2-Phase Step-UP
DC/DC Controller
DESCRIPTION
The LT^®3782 is a current mode two 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 LT3782 can drive most industrial grade high power
MOSFETs with high efficiency. For synchronous applica-
tions, the LT3782 provides synchronous gate signals with
programmable falling edge delay to avoid cross conduc-
tion 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 LT3782 is available in thermally enhanced 28-lead
TSSOP and 4mm × 5mm QFN packages.
For new designs use the LT3782A which has improved
phase matching
L, 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
C_IN
10μF
50V
2x
100pF
50V 4A Boost Converter
V_CC
GBIAS1
R6
1μF
825k
GBIAS2
GBIAS
RUN
R8
BGATE1
274k
LT3782
R_SLOPE
59k
R_FREQ
80k
SLOPE
DELAY
DCL
R_SET
V_EE1
BGATE2
V_EE2
SS
0.1μF
SENSE1⁺
V_C
13k
6.8nF
SENSE1^–
SENSE2⁺
SENSE2^–
GND
FB
L1
+ _{C3 L2}
2μF
D1
30BQ060
M1
Si7852dp
2x
D2
30BQ060
R_S1
0.004Ω
M2
Si7852dp
2x
R_S2
0.004Ω
C_OUT1
10μF
50V
2x ₊
V_OUT
50V, 4A
C_OUT2
220μF
L1, L2: PB2020.223
C_IN, C_OUT1: X7R, TDK
10Ω
10Ω
10nF
10nF
R_F1
475k
3782 TA01
R_F2
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)
3782 TA01b
3782fg
1