®

TYPICAL CHARACTERISTICS

SYNC AND INHIBIT

RECOMMENDED OPERATING CONDITIONS

ABSOLUTE MAXIMUM RATINGS

Input Voltage

• 16 to 40 VDC

Output Power

• 25 to 30 watts depending on model

Lead Soldering Temperature (10 sec per pin)

• 300°C

Storage Temperature Range (Case)

• –65°C to +135°C

2

SMTR SERIES

30 WATT

Output Voltage Temperature Coefficient

• 100 ppm/°C typical single and dual outputs

• 200 ppm/°C main, 300 ppm/°C aux

triple output

Input to Output Capacitance

• 50 pF typ (100 pF typ triple outputs)

Current Limit

• 115% of full load typical

Isolation

• 100 megohm minimum at 500 V

Audio Rejection

• 40 dB typ (50 dB typ triple output)l

Conversion Frequency

• Free run 550 min, 600 typ, 650 max kHz

• External sync 500 to 675 kHz

Inhibit Pin Voltage (unit enabled)

• 9 to 11 V

Input Voltage Range

• 16 to 40 VDC continuous

• 50 V for 50 msec transient

Case Operating Temperature (Tc)

• –55°C to +125°C full power

• –55°C to +135°C absolute

Derating Output Power/Current

• Linearly from 100% at 125°C to 0% at 135°C

Sync (500 to 675 kHz)

• Duty cycle 40% min, 60% max

• Logic low 0.8 V max

• Logic high 4.5 V min, 5 V max

• Referenced to input common

• If not used, connect to input common

Inhibit TTL Open Collector

• Logic low (output disabled)

Voltage

≤0.8 V

Inhibit pin current 8.0 mA max

• Referenced to input common

• Logic high (output enabled)

Open collector

Notes

1. Tc = –55°C to +125°C

2. Operation is limited below 16V (see Figure 21).

3. Tested with 3300 pF ceramic bypass capacitors connected externally from

input common to case and output common to case.

4. Indefinite short circuit protection not guaranteed above 125°C case.

5. Recovery time is measured from application of the transient to point at which

Vout is within 1% of final value.

6. Transition time

≥10 µs.

Electrical Characteristics: 25°C Tc, 28 VDC Vin, 100% load, radiation level O, unless otherwise specified.

SINGLE OUTPUT MODELS

SMTR283R3S

SMTR2805S

SMTR2812S

SMTR2815S

PARAMETER

CONDITION

MIN

TYP

MAX

MIN

TYP

MAX

MIN

TYP

MAX

MIN

TYP

MAX

UNITS

OUTPUT VOLTAGE

3.27

3.30

3.33

4.95

5.00

5.05 11.88 12.00 12.12 14.85 15.00 15.15

VDC

0

––

5.45

0

—

5.0

0

—

2.5

0

—

2.0

A

0

—

18

0

—

25

0

—

30

0

—

30

W

OUTPUT RIPPLE

10 kHz – 2 MHz

—

15

40

—

35

40

—

25

40

—

25

40

mV p-p

VOLTAGE

Tc = –55°C TO +125°C

—

—

50

—

50

90

—

40

90

—

40

90

Vin = 16 to 40 VDC

Tc = –55°C TO +125°C

—

—

20

—

15

50

—

15

50

—

15

50

mV

LOAD REGULATION

NO LOAD TO FULL

Tc = –55°C TO +125°C

—

—

20

—

15

50

—

15

50

—

15

50

mV

CONTINUOUS

16

28

40

16

28

40

16

28

40

16

28

40

VDC

NO LOAD TO FULL

TRANSIENT 50 ms

—

—50—

—50

—

—50—

—50

V

NO LOAD

—

30

75

—

35

75

—

35

75

—

35

75

mA

FULL LOAD

—

0.94

—

—

1.15

—

—

1.30

—

—

1.25

—

A

INHIBITED

—

7

8

—

3

8

—

3

8

—

3

8

mA

INPUT RIPPLE

10 kHz – 10 MHz

Tc = –55°C TO +125°C

—

25

50

—

20

50

—

20

50

—

20

50

mA p-p

EFFICIENCY

74

76

—

74

78

—

78

83

—

79

84

—

%

SHORT CIRCUIT

POWER DISSIPATION

—

—

10

—

—

10

—

—

10

—

—

10

W

—

1.4

6

—

1.4

5

—

1.4

5

—

1.4

5

ms

STEP LOAD RESP.

50% – 100% – 50%

TRANSIENT

—

±125 ±250

—

±200 ±300

—

±250 ±400

—

±350 ±500

mV pk

—

—

200

—

60

200

—

60

200

—

60

200

µs

STEP LINE RESP.

16 – 40 – 16 VDC

—

—

±300

—

±200 ±300

—

±400 ±500

—

±500 ±600

mV pk

—

—

300

—

—

300

—

—

300

—

—

300

µs

DELAY

—

1.4

5

—

1.4

5

—

1.4

5

—

1.4

5

ms

OVERSHOOT

FULL LOAD

—

0

50

—

0

50

—

0

120

—

0

150

mV pk

NO LOAD

—

33

150

—

50

250

—

120

600

—

150

750