LTC3810-5
60V Current Mode
Synchronous Switching
Regulator Controller
Description
Features
High Voltage Operation: Up to 60V
n Large 1Ω Gate Drivers
n No Current Sense Resistor Required
n Dual N-Channel MOSFET Synchronous Drive
n Extremely Fast Transient Response
n ±0.5% 0.8V Voltage Reference
n Programmable Output Voltage Tracking/Soft-Start
n Generates 5.5V Driver Supply from Input Supply
n Synchronizable to External Clock
n Selectable Pulse Skip Mode Operation
n Power Good Output Voltage Monitor
n Adjustable On-Time/Frequency: t
ON(MIN) < 100ns
n Adjustable Cycle-by-Cycle Current Limit
n Programmable Undervoltage Lockout
n Output Overvoltage Protection
n 5mm × 5mm QFN Package
The LTC®3810-5 is a synchronous step-down switching
regulator controller that can directly step-down voltages
from up to 60V, making it ideal for telecom and automotive applications. The LTC3810-5 uses a constant on-time
valley current control architecture to deliver very low duty
cycles with accurate cycle-by-cycle current limit, without
requiring a sense resistor.
n
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 drivers
allow the LTC3810-5 to drive multiple MOSFETs for higher
current applications. The operating frequency is selected
by an external resistor and is compensated for variations
in VIN and can also be synchronized to an external clock
for switching-noise sensitive applications. A shutdown
pin allows the LTC3810-5 to be turned off, reducing the
supply current to 240µA.
Applications
48V Telecom and Base Station Power Supplies
n Networking Equipment, Servers
n Automotive and Industrial Control Systems
n
L, LT, LTC, LTM, Linear Technology, the Linear logo and No RSENSE are registered trademarks
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.
Integrated bias control generates gate drive power from
the input supply during start-up or when an output shortcircuit occurs, with the addition of a small external SOT23
MOSFET. When in regulation, power is derived from the
output for higher efficiency.
Typical Application
Efficiency vs Load Current
High Efficiency High Voltage Step-Down Converter
ION
VRNG
SS/TRACK
BOOST
TG
5pF
10µH
DRVCC
SENSE+
SGND
+
MBR1100
270µF
Si7450DP
BG
SENSE–
BGRTN
95
VIN = 42V
90
14k
INTVCC
VFB
VOUT
12V/6A
EXTVCC
ITH
200k
Si7450DP
0.1µF
SW
SHDN
47pF
VIN = 24V
LTC3810-5
MODE/SYNC
1000pF
22µF
ZXMN10A07F
NDRV
PGOOD
+
100k
100
EFFICIENCY (%)
274k
VIN
13V TO 60V
1µF
85
0
1
2
3
4
LOAD CURRENT (A)
5
6
38105 TA01b
1k
38105 TA01
38105fd
1
