DC-DC CONVERTERS 72-165 W High Efficiency DC-DC Converters 1
2 YEAR WARRANTY
EXB250 Series
Single output
•High efficiency topology, 90% typical at 3.3 V
•Industry standard footprint
•Wide baseplate temperature, -40 ˚C to +100 ˚C
(natural convection)
•90% to 110% output trim
•No minimum load
•Overvoltage protection
•Remote ON/OFF
•Available RoHS compliant
The EXB250 is a new high efficiency, open-frame, isolated 165 Watt converter series in an
industry standard half-brick footprint. The EXB250 delivers very high output current at low
voltages, and excellent useable power density for today’s high end applications. The design takes
advantage of open frame construction to provide a low weight, low thermal impedance baseplate
design. The seven models in the series feature an input voltage range of 33 Vdc to 75 Vdc and
are available in output voltages of 12 V, 5 V, 3.3 V, 2.5 V, 1.8 V, 1.5 V and 1.2 V. The output voltage
on each model is adjustable from 90% to 110% of the nominal value. Typical efficiencies for the
models are 90% for the 3.3 V, 88% for the 2.5 V and 87% for the 1.8 V version. The EXB250
series also has a remote ON/OFF capability. Overcurrent and overvoltage protection features are
included as standard. With full international safety approval including EN60950 (TÜV Rheinland)
and UL/cUL1950, the EXB250 reduces compliance costs and time to market.
All specifications are typical at nominal input, full load at 25 °C unless otherwise stated
OUTPUT SPECIFICATIONS
Voltage adjustability 90% to 110%
Set point accuracy ±1.6% max.
Line regulation 1.2 V model ±0.2% max.
Low line to high line All other models ±0.1% max.
Load regulation Full load to min. load ±0.2% max.
Minimum load 0%
Overshoot At turn-on and turn-off None
Undershoot 1.2 V, 1.5 V (Z), 1.8 V (Z), None
2.5 V (Z) and 3.3 V (Z) models
Ripple and noise 5 Hz to 20 MHz 60 mV pk-pk
20 mV rms
Transient response 6% max. deviation
(See Note 1) 150 µs recovery to
within total error band
INPUT SPECIFICATIONS
Input voltage range 48 Vin nominal 33-75 Vdc
Input current No load 145 mA max.
Remote OFF 35 mA max.
Input current (max.) 5.7 A max. @ Io max.
(See Note 3) and Vin = 33-75 Vdc
Input reflected ripple (See Note 5) 350 mA (pk-pk) typ.
Active high remote ON/OFF
Logic compatibility Open collector ref to -input
ON Open circuit or >4.0 Vdc
OFF <1.2 Vdc
Undervoltage lockout Power up 32.5 V (typ.)
Power down 30.5 V (typ.)
Start-up time Power up 10 ms (typ.)
(See Note 6) Remote ON/OFF 3 ms (typ.)
SPECIFICATIONS
File Name: exb250s.pdf Rev (02): 06 Dec 2005
TÜV
EMC CHARACTERISTICS
Conducted emissions EN55022 (See Note 2) Level A
EN55022 (See Note 2) Level B
Immunity:
ESD air EN61000-4-2 8 kV (NP), 15 kV (NP)
ESD contact EN61000-4-2 6 kV (NP), 8 kV (NP)
Radiated field enclosure EN61000-4-3 10 V/m (NP)
Conducted (DC power) EN61000-4-6 10 V (NP)
Conducted (signal) EN61000-4-6 10 V (NP)
Input transients ETS 300 132-2, ETR 283
GENERAL SPECIFICATIONS
Efficiency See table
Operational Input/output 1500 Vdc
Input/baseplate 1500 Vdc
Switching frequency Fixed 400 kHz typ.
Approvals and EN60950 (TÜV Rheinland)
standards (See Note 4) UL/cUL1950
Material flammability UL94V-0
Weight 73 g (2.6 oz)
MTBF Telcordia SR-332 1,598,243 hours
@ 25 °C, 100% load
ground benign
Demonstrated >2,000,000 hours
ENVIRONMENTAL SPECIFICATIONS
Thermal performance Operating baseplate -40 °C to +100 °C
temperature
Non-operating -40 °C to +125 °C