LTC3810-5
1
38105fd
60V Current Mode
Synchronous Switching
Regulator Controller
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 automo-
tive 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.
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 V
IN
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.
Integrated bias control generates gate drive power from
the input supply during start-up or when an output short-
circuit occurs, with the addition of a small external SOT23
MOSFET. When in regulation, power is derived from the
output for higher efficiency.
n
48V Telecom and Base Station Power Supplies
n
Networking Equipment, Servers
n
Automotive and Industrial Control Systems
n
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
High Efficiency High Voltage Step-Down Converter
Efficiency vs Load Current
Typical applicaTion
FeaTures
applicaTions
DescripTion
L
, LT, LTC, LTM, Linear Technology, the Linear logo and No R
SENSE
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.
PGOOD
MODE/SYNC
V
RNG
I
TH
V
FB
SGND
SS/TRACK
I
ON
1000pF
47pF
5pF
V
IN
13V TO 60V
22µF
V
OUT
12V/6A
ZXMN10A07F
200k
LTC3810-5
EXTV
CC
TG
SW
SENSE
–
BG
BGRTN
SENSE
+
DRV
CC
INTV
CC
NDRV
BOOST
38105 TA01
0.1µF
274k
100k
Si7450DP
Si7450DP
1µF
MBR1100
14k
1k
270µF
10µH
SHDN
+
+
LOAD CURRENT (A)
0
85
EFFICIENCY (%) 90
95
100
1
2
3
4
38105 TA01b
5
6
V
IN
= 24V
V
IN
= 42V
