®
®
INNOVATION and EXCELLENCE
Single Output
UNR Series
Non-Isolated, 1.8/2.5/3.3VOUT
3.6-10W DC/DC Converters
DATEL's 3.6-10W UNR Series consists of non-isolated, 5V-to-1.8V (2A), 5V-to-
2.5V (2A), 5V-to-3.3V (3A), and 12V-to-3.3V (3A) DC/DC converters in miniature,
1" x 1" surface-mount and through-hole packages. The "gull-wing" packages (with
metal shells and non-conductive plastic baseplates) weigh a mere 17 grams and
can withstand temperatures up to +235°C. They are compatible with virtually all
contemporary pick-and-place and solder-reflow processes.
The true benefits of distributed power will ultimately be realized only when
every low-voltage, high-current CPLD, ASIC, DSP, etc. has its own "power plant"
right next to it. With isolated DC/DC converters inevitably residing at the edges of
boards in proximity with backplanes and power buses, the "on-board" proliferation
of distributed power will continue with more cost-effective, non-isolated devices. The
low-cost, easy-to-use (no external components required), highly reliable (100% fully
automated SMT construction) 3.6-10W UNR Series makes this power processing at
the concluding point of use a practical reality today.
These versatile DC/DC's are fully line and load regulated. They feature user-
optional on/off control (for power-sequencing requirements), output current limiting,
and short-circuit protection (foldback technique with auto-recovery). Additionally, the
12V-to-3.3V model offers input undervoltage lockout (at 9.6V). Their impressive
guaranteed efficiencies enable all models to deliver their fully rated output power
from –40 to +70°C (ambient) without heat sinking or forced-air cooling.
If you've already considered and rejected the use of inefficient, step-down,
linear regulators, take a look at one of these new switching buck regulators. Their
high efficiency, ease-of-use, long-term reliability, and overall cost effectiveness will
impress you. Safety agency approvals are currently in progress.
Features
Low cost! High reliability!
1" x 1" SMT, 1" x 1" Through-hole packages
Gull-wing leads; Standard reflow
Complete; No external components
Outputs: 1.8V/2A, 2.5V/2A, 3.3V/3A
Inputs: 4.75-5.5V, 10.8-13.6V
Guaranteed efficiencies to 87%
Output noise as low as 30mVp-p
Transient response as quick as 20µsec
–40 to +70°C operation with no derating
On/off control; EMC compliant
IEC950/EN60950/UL1950 approvals
Modifications and customs for OEM's
+VOUT
+VIN
➀
OUTPUT
RETURN
INPUT
RETURN
➀
LOGIC
GROUND
CURRENT LIMITING
& S.C. SHUTDOWN
UNDERVOLTAGE
SHUTDOWN
PWM
CONTROLLER
ON/OFF
CONTROL
REFERENCE &
ERROR AMP
➀ "D5" models do not have input undervoltage shutdown.
➀ "D5" models employ a more traditional buck-regulator design
in which this FET is replaced with a power Schottky diode.
Figure 1. Simplified Schematic
DATEL, Inc., Mansfield, MA 02048 (USA)
•
Tel: (508)339-3000, (800)233-2765 Fax: (508)339-6356
•
Email: sales@datel.com • Internet: www.datel.com