1
Rev. 0
DESCRIPTION
LT7182S
Dual Channel 6A, 20V, PolyPhase
Step-Down Silent Switcher with Digital
Power System Management
Demonstration Circuit 2836A is a dual-output PolyPhase
®
DC/DC synchronous step-down regulator with 4V to 20V
input range featuring
. Each output can sup-
ply 6A continuous/9A maximum transient load current.
LT7182S is a dual 6A monolithic step-down regulator.
The second-generation Silent Switcher
®
structure is
incorporated into LT7182S to minimize EMI and reduce
PCB layout sensitivity. It also integrates digital power sys-
tem management function allowing for programmability
and telemetry with a PMBus/I
2
C compliant serial inter-
face. Please see LT7182S data sheet for more detailed
information.
The demonstration circuit 2836A runs at 1MHz to mini-
mize solution size. The peak efficiency at 12V input is
83.2% for 1.2V rail and 91.1% for 3.3V rail. The IC tem-
perature rise is 70°C when both channels run at full load,
6A each, at 1MHz.
The demo board has EMI filters installed for both chan-
nels. The conducted and radiated EMI performances of
the board (with EMI filters) are shown in Figure 2. The red
lines in Figure 2 are CISPR25 CLASS 5 limit.
All registered trademarks and trademarks are the property of their respective owners.
PERFORMANCE SUMMARY
DC2836A powers up to default settings and produces
power based on configuration resistors without the need
for any serial bus communication. This allows easy evalu-
ation of the DC/DC converter. To fully explore the power
system management features of the part, download the
GUI software LTpowerPlay
®
onto your PC and use ADI’s
I
2
C/SMBus/PMBus dongle DC1613A to connect to the
board. LTpowerPlay allows the user to reconfigure the part
on the fly and store the configuration in EEPROM, view
telemetry of voltage, current, temperature and fault status.
GUI Download
The software can be downloaded from:
The LT7182S data sheet gives a complete description of
the part, operation and application information. The data
sheet must be read in conjunction with this demo manual
for DC2836A.
For more details and instructions of LTpowerPlay, please
refer to LTpowerPlay GUI for LT7182S Quick Start Guide.
Design files for this circuit board are available
Specifications are at T
A
= 25°C
SYMBOL
PARAMETER
CONDITIONS
MIN
TYP
MAX
UNITS
V
IN
Input Voltage Range
4
20
V
V
OUT0
Output0 Voltage
1.2
V
I
OUT0
Maximum Output0 Current
9
A
V
OUT1
Output1 Voltage
3.3
V
I
OUT1
Maximum Output1 Current
9
A
f
SW
Switching Frequency
0.925
1
1.075
MHz
EFE
Efficiency at DC
V
IN
= 12V, I
OUT0
= 3A, I
OUT1
= 0A
V
IN
= 12V, I
OUT1
= 3A, I
OUT0
= 0A
83.2
91.1
%
%
