LTC3814-5_15 Datasheet, PDF (1/30 Pages) Linear Technology – 60V Current Mode Synchronous Step-Up Controller

LTC3814-5
60V Current Mode
Synchronous Step-Up Controller
FEATURES
n _{High Output Voltages: Up to 60V}
n _{Large 1Ω Gate Drivers}
n _{No Current Sense Resistor Required}
n _{Dual N-Channel MOSFET Synchronous Drive}
n _{±0.5% 0.8V Voltage Reference}
n _{Fast Transient Response}
n _{Programmable Soft-Start}
n _{Generates 5.5V Driver Supply}
n _{Power Good Output Voltage Monitor}
n _{Adjustable Off-Time/Frequency: tOFF(MIN) < 100ns}
n _{Adjustable Cycle-by-Cycle Current Limit}
n _{Undervoltage Lockout On Driver Supply}
n _{Output Overvoltage Protection}
n _{Thermally Enhanced 16-Pin TSSOP Package}
APPLICATIONS
n _{24V Fan Supplies}
n _{48V Telecom and Base Station Power Supplies}
n _{Networking Equipment, Servers}
n _{Automotive and Industrial Control Systems}
DESCRIPTION
The LTC3814-5 is a synchronous step-up switching regu-
lator controller that can generate output voltages up to
60V. The LTC3814-5 uses a constant off-time peak current
control architecture to deliver very high duty cycles with
accurate cycle-by-cycle current limit without requiring a
sense resistor.
A precise internal reference provides ±0.5% DC accuracy.
A high bandwidth (25MHz) error amplifier provides very
fast line and load transient response. Large 1Ω gate driv-
ers allow the LTC3814-5 to drive large power MOSFETs
for higher current applications. The operating frequency
is selected by an external resistor and is compensated for
variations in V_IN. A shutdown pin allows the LTC3814-5
to be turned off reducing the supply current to <230μA.
L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and No R_SENSE
is a trademark of Linear Technology Corporation. All other trademarks are the property of their
respective owners. Protected by U.S. Patents including 5481178, 5847554, 6304066, 6476589,
6580258, 6677210, 6774611.
TYPICAL APPLICATION
High Efficiency High Voltage Step-Up Converter
V_OUT
PGOOD
263k
100k
1000pF
0.01μF
100k
100pF
I_OFF
NDRV
PGOOD
BOOST
LTC3814-5
V_RNG
TG
V_OFF
SW
RUN/SS
EXTV_CC
INTV_CC
I_TH
BG
V_{FB SGND} PGND
+
4.7μH
V_IN
4.5V TO 14V
22μF
0.1μF
M1
Si7848DP
V_OUT
24V
4A
D1
M2 ^MBR1100
Si7848DP
1μF
29.4k₊
270μF
×2
1k
38145 TA01
Efficiency vs Load Current
100
V_IN = 12V
95
90
V_IN = 5V
85
80
0
1
2
3
4
LOAD (A)
38145 TA01b
38145fc
1