DC-DC CONVERTERS

20-50 W High Efficiency DC-DC Converters

1

2 YEAR WARRANTY

EXB50 Series

Single output

(natural convection)

The EXB50 series of 50 Watt single-output isolated dc-dc converters are specifically

designed to meet the power needs of low-voltage silicon. Housed in an open-frame

package with an industry-standard footprint, these latest-generation converters offer

efficiencies as high as 91%. The series comprises three 24 V input models with 5 V,

3.3 V and 2 V outputs, and six 48 V input models with 12 V, 5 V, 3.3 V 2.5 V, 2 V and

1.8 V outputs. All models feature a wide input range, trimmable output voltage and a

10 A current rating (except the 12 V). Remote sense and remote ON/OFF facilities are

included as standard, and the converters are comprehensively protected against

overcurrent, overvoltage and overtemperature conditions.

All specifications are typical at nominal input, full load at 25 °C unless otherwise stated

SPECIFICATIONS

OUTPUT SPECIFICATIONS

Voltage adjustability

60% to 110%

Setpoint accuracy

±1.5% max.

Line regulation

Low line to high line

0.1% max.

Load regulation

Full load to min. load

0.2% max.

Total error band

±3.0%

Minimum load

0%

Overshoot

At turn-on and turn-off

None

Undershoot

None

Ripple and noise

5 Hz to 20 MHz

100 mV pk-pk

(See Note 1)

20 mV rms

Transient response

24 V models

3.0% peak deviation

(See Notes 2 and 8)

48 V models

2.0% peak deviation,

200 µs recovery to

within total error band

Remote sense

(See Note 9)

10% o/p voltage change

INPUT SPECIFICATIONS

Input voltage range

24 V nominal

18-36 Vdc

48 V nominal

36-75 Vdc

(See Note 14)

100 V 100 ms transient

Input current

24 V no load

85 mA max.

24 V Remote OFF

20 mA max.

48 V no load

60 mA max.

48 V Remote OFF

10 mA max.

Input current (max.)

24 V models

3.25 A max. @ Io max.

(See Note 4)

and Vin = 18-36 Vdc

48 V models

1.7 A max. @ lo max.

and Vin = 36-75 Vdc

Input reflected ripple

24 V models

20 mA (pk-pk) typ.

(See Note 6)

48 V models

50 mA (pk-pk) typ.

Remote ON/OFF

(See Note 15)

Logic compatibility

Open collector ref to -input

ON

Open circuit or >2 Vdc

OFF

<1.2 Vdc

File Name: exb50s.pdf Rev (02): 05 Dec 2005

INPUT SPECIFICATIONS Continued

Undervoltage lockout

24 V Power up

17 V max.

24 V Power down

15 V min.

48 V Power up

33.2 V max.

48 V Power down

30.9 V min.

Start-up time

Power up

30 ms

(See Note 7)

Remote ON/OFF

25 ms

EMC CHARACTERISTICS

Conducted emissions

EN55022 (See Note 3)

Level A

EN55022 (See Note 3)

Level B

Radiated emissions

EN55022

Level A

Immunity:

(See Note 13)

ESD air

EN61000-4-2 8 kV (NP), 15 kV (RP)

ESD contact

EN61000-4-2 6 kV (NP), 8 kV (RP)

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)

GENERAL SPECIFICATIONS

Efficiency

See table

Basic insulation

Input/output

1500 Vdc

Switching frequency

Fixed

300 kHz typ.

Approvals and

IEC60950/EN60950, UL/cUL1950

standards (See Note 5)

CSA C22.2 No. 950

Material flammability

UL94V-0

Weight

50 g (1.77 oz)

MTBF

MIL-HDBK-217F @ 25 ºC

270,000

100% load ground benign

hours

ENVIRONMENTAL SPECIFICATIONS

Thermal performance

Operating ambient.

-40 °C to +70 °C

(See Notes 11, 12)

temperature (natural convection)

Non-operating

-55 °C to +125 °C

ETS 300 019-2-3

Classes T3.1 to T3.5

Altitude

3,000 metres

Derate max. output

(See Note 10)

current by 20%

10,000 metres

Derate max. output

current by 50%