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dc2055afa
DEMO MANUAL DC2055A
DESCRIPTION
LTC3875EUJ
High Efficient, Single Output
Synchronous Buck Converter
with Very Low DCR Inductor
Demonstration circuit 2055A is a high efficiency, high
density, 4-phase synchronous buck converter with a 4.5V
to 14V input voltage range. It can supply up to 120A of
load current with a 1.0V output. This demo board has two
each
LTC
®
3875EUJ
feature-rich dual-phase synchronous
current mode buck controllers with very low DCR current
sensing capability, on-chip drivers and remote output volt-
age sensing. This board is set up with 0.32mΩ DCR output
inductors. The temperature compensation function can
guarantee accurate current limit over a wide temperature
range with DCR sensing.
The LTC3875 is suitable for inputs from 4.5V to 38V and
outputs up to 3.5V. It can provide a high efficiency, high
power density and versatile power solution for telecom
and datacom systems, industrial, medical instruments,
L
, LT, LTC, LTM, Linear Technology, the Linear logo and Burst Mode are registered trademarks
of Linear Technology Corporation. All other trademarks are the property of their respective
owners.
PERFORMANCE SUMMARY
Specifications are at T
A
= 25°C
and DC power distribution. The LTC3875 is available in a
40-lead 6mm
×
6mm QFN package.
To shut down the converter, set the RUN pin voltage below
1.0V (SW1 and SW2: both OFF). Use JP1 jumper to select
Burst Mode
®
operation, pulse-skipping mode or forced
continuous mode operation at light load. The switching
frequency is pre-set at about 400kHz, and it can be easily
modified from 250kHz to 720kHz. An onboard dynamic
circuit is also available for a load transient test. Please
see LTC3875 data sheet for more detailed information.
Design files for this circuit board are available at
http://www.linear.com/demo
PARAMETER
CONDITION
VALUE
Input Voltage Range
4.5V to 14V
Output Voltage, V
OUT
V
IN
= 4.5 to 14V, I
OUT
= 0A to 120A
1.0V ±2%
Maximum Output Current, I
OUT
V
IN
= 4.5 to 14V, V
OUT
= 1.0V
120A
Typical Efficiency, V
OUT
V
IN
= 12V, V
OUT
= 1.0 V, I
OUT
= 120A
87.1%, See Figure 3
Typical Switching Frequency
400kHz
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