Powering Freight & Transportation - Power Systems Design

NEW PRODUCTS NEW PRODUCTS
Compact Buck-Boost Regulators wth Ultra-Fast Switching
Analog Devices has introduced one
of the industry’s smallest buck-boost
regulators—and the first to support
switching frequencies at speeds up to
2.5 MHz. Designed to regulate voltages
above and below the battery output
voltage in portable electronics, ADI’s
ADP2503 and ADP2504 step-up/stepdown
dc-to-dc regulators incorporate
a patent-pending architecture that
delivers seamless mode transitions. The
ultra-fast switching speed of the new
regulators allows designers to use lowcost
multilayer inductors that are half
the size of other solutions. In addition,
the total external component count has
been reduced to three, resulting in a
total PCB area of less than 13mm 2 and
a height of less than 1mm, making the
solution ideal for space-constrained
applications such as wireless handsets,
digital still cameras, portable audio
players and USB-powered consumer
and industrial devices.
“Many lithium-battery-powered
devices require voltage rails in the
2.8-V to 3.6-V range for RF, audio, or
motor applications. The ADP2503 and
ADP2504 are ideal regulators to provide
these voltages when board area and
efficiency are important,” said Arcadio
Leon, marketing director for portable
power products, Analog Devices.
The ADP2503 and ADP2504
regulators are based on ADI’s new
proprietary current-mode buck-boost
architecture, achieving glitchless mode
transitions and outstanding transient
performance across line and load. This
high level of output stability is critical for
powering sensitive analog and digital
circuitry. The devices also feature one of
the industry’s lowest no-load quiescent
current (Iq) levels - 38 µA in power-save
mode - which extends stand-by time in
portable electronics and/or increases
the power budget for the inclusion of
additional features. The proprietary
H-Bridge buck-boost architecture
improves the efficiency by more than
10 percent versus legacy cascaded
boost-buck architectures by reducing
switching losses.
The ADP2503 and ADP2504 operate
at input voltages ranging from 2.3V and
5.5V, which meets the requirements for
single Li-Ion, Li-Ion polymer cell and
multiple alkaline/NiMH cell applications.
Fixed output voltages range from 2.8V
to 5V.
ADP2503 and ADP2504 are available
now in sample quantities and come
housed in a 10-lead 3-mm x 3-mm
thin LFCSP package. The buck-boost
regulators are priced at $1.40 per unit in
1,000-unit quantities.
electronica: Hall A4 Stand 159
Step-Down Converter Draws Only 75uA Quiescent -
Withstands 62V Transients
33VIN, 62V Transient Protection Buck
Regulator
Linear Technology Corporation
announces the LT3972, a 3.5A,
33VIN step-down switching regulator
with Burst Mode ® operation to keep
quiescent current under 75uA. The
LT3972 operates within a VIN range of
3.6V to 33V, with overvoltage lockout
protection against transients as high
as 62V, making it ideal for load dump
and cold-crank conditions commonly
found in automotive applications. Its
internal 4.6A switch can deliver up to
3.5A of continuous output current at
voltages as low as 0.79V. Its Burst Mode
operation provides ultra-low quiescent
current, well suited for applications
such as automotive or telecom systems,
which have always-on circuits and
need to optimize battery life. Switching
frequency is user programmable
from 200kHz to 2.4MHz, enabling
the designer to maximize efficiency
while avoiding critical noise-sensitive
frequency bands. Its 3mm x 3mm
DFN-10 package (or thermally enhanced
MSOP-10E), and high switching
frequency keep external inductors and
capacitors small, providing a compact,
thermally efficient footprint.
The LT3972 utilizes a high efficiency
4.6A, 95mOhm switch, with the
necessary boost diode, oscillator,
control and logic circuitry integrated into
a single chip. Low ripple Burst Mode
operation maintains high efficiency
at low output currents while keeping
www.analog.com
output ripple below 15mVPK-PK. Special
design techniques used in the
LT3972 enable high efficiency over
a wide input voltage range, and the
device’s current mode topology enables
fast transient response and excellent
loop stability. Other features include
external synchronization (from 250kHz
to 2MHz), a power good flag and softstart
capability.
Pricing for the LT3972EDD and
LT3972EMSE starts at $4.25 and $4.35
each, respectively for 1,000-piece
quantities. The LT3972IDD and
LT3972IMSE are guaranteed to operate
from a -40°C to 125°C operating
junction temperature, priced at $5.10
and $5.22 each, respectively in
1,000-piece quantities. All versions are
available from stock.
electronica: Hall A4 Stand 538
Hall A5 Stand 568
www.linear.com
New Surface mount & radial leaded inductors reduce EMI
Murata Power Solutions has
enhanced its radial lead and toroidal
surface-mount inductor portfolios
with the addition of four new ranges
of RoHS compliant components. The
introductions comprise over 50 new part
numbers that reinforce Murata Power
Solutions’ reputation as a provider of
industry-leading magnetic products.
The 1500 and 1900R series are
general purpose radial leaded inductors
suitable for providing filtering in low
to medium current applications such
as those found in power supplies.
The 4200 and 4300 series of toroidal
surface-mount inductors meanwhile are
designed for use in switching AC/DC
power supplies and DC/DC converters.
Their low-profile design makes
them ideal for use in designs where
component height is restricted.
Both the 1500 and 1900R series offer
low DC resistance. The 1500 series is
available with current ratings up to 16.2A
IDC and inductance values that range
from 1.0µH to 1.0mH. The 1900R series
is rated to 7.8A IDC with inductance
values of between 4.7µH and 100mH.
Custom parts are available on request.
Both ranges are supplied in cartons
of 40, are fully compatible with RoHS
soldering systems and have backward
compatibility to Sn/Pb solder processes.
Operating free air temperature range is
-40ºC to +85ºC.
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automotiv.tlmatics.snsors.infotainmnt.scurity.
The 4200 and 4300 series toroidal
surface-mount inductors have
compact overall dimensions with a
maximum overall height of less than
10mm. Both ranges utilise UL94 V-0
package materials, are pick & place
compatible and meet J-STD-020C
reflow requirements with backward
compatibility to Sn/Pb soldering
systems. The toroidal construction of
the new inductors aids design engineers
by helping minimize EMI issues. The
4200 series has a current rating of up to
15.4A IDC and a choice of inductance
values between 1.27µH and 17.6µH.
The 4300 series comprises parts with
inductance values ranging from 2.1µH
to 4.0µH and a maximum current rating
of 22.4A IDC. Operating temperature for
both ranges is -40ºC to +125ºC.
electronica: Hall B2 Stand 431
www.murata-ps.com
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www.powersystemsdesign.com
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