LEN-D12 Models
Non-Isolated, 28A Eighth Brick
DC/DC Converters
NOT RECOMMENDED
FOR NEW DESIGNS
FEATURES
Typical Units
Non Isolated, 12VIN, 0.8-5VOUT
28 Amp DC/DC Converters
PRODUCT OVERVIEW
Eighth brick, through hole or SMT
The LEN D12 Series of non-isolated eighth
bricks are ideal building blocks for emerging, on-board power-distribution schemes
in which isolated 12V buses deliver power
to any number of non-isolated, step-down
buck regulators. LEN D12 DC/DCs accept a
12V input (10.2V to 13.8V input range) and
convert it, with the highest efficiency in the
smallest space, to a 0.8, 1, 1.2, 1.5, 1.8, 2,
2.5, or 3.3 Volt output fully rated at 28 Amps,
or 5 Volt output at 25 Amps.
LEN D12s are ideal POLPP's (point-of-use/
load power processors) and they typically require no external components. They occupy the
standard eighth-brick board space (0.9" x 2.3")
and come in either through-hole packages or
surface-mount packages with a profile of only
0.46" (0.5" including optional heat sink).
The LEN's best-in-class power density is
achieved with a fully synchronous,fixedfrequency, 2-phase buck topology that deliv-
2-phase buck regulators for new
distributed 12V power architectures
12V input (10.2-13.8V range)
0.8-2.5VOUT, 3.3VOUT @ 28A, 5VOUT @ 25A
Non-isolated, fixed-frequency
Synchronous-rectifier topology
Efficiencies to 95% @ 25 Amps
Noise as low as 25mVp-p
Stable no-load operation
On/Off control, trim & sense functions
Input Over/Undervoltage lockout
Thermal shutdown
Designed to meet UL/EN/IEC60950-1
EMC compliant
ers extremely high efficiency (95% for 5VOUT
models), low noise (25mVp-p typ.), tight
line/load regulation (±0.25% max.), quick
step response (150μsec), stable no-load
operation, and no output reverse conduction.
The fully functional LEN's feature input
over/undervoltage lockout, output overvoltage and overcurrent detection, continuous
short-circuit protection, overtemperature
protection, an output-voltage trim function,
a remote on/off control pin, and a sense pin.
High efficiency enables the LEN D12s to
deliver rated output currents of 25 Amps at
ambient temperatures to +65°C with 200 lfm
air flow without heat sink.
If your new system boards call for multiple
supply voltages, check out the economics of
on-board 12V distributed power. If you don't
need to pay for multiple isolation barriers,
MPS’s non-isolated ¼ and 1∕8 brick’s will save
you money.
For full details go to
www.murata-ps.com/rohs
Typical topology is shown
+OUTPUT
(7,9)
+INPUT
(5)
+SENSE
(10)
COMMON
(6, 8)
COMMON
(1)
CURRENT
SENSE
VCC
ON/OFF
CONTROL
(4)
2-PHASE
PWM
CONTROLLER
Figure 1. Simplified Schematic
www.murata-ps.com
REFERENCE &
ERROR AMP
Only one phase of two shown.
VOUT
TRIM
(2)
Technical enquiries email: sales@murata-ps.com, tel: +1 508 339 3000
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