TYPICAL CHARACTERISTICS

SYNC AND INHIBIT

RECOMMENDED OPERATING CONDITIONS

ABSOLUTE MAXIMUM RATINGS

Input Voltage

• 16 to 40 V

Output Power

• 15 to 20 watts depending on model

Lead Soldering Temperature (10 sec per lead)

• 300°C

Storage Temperature Range (Case)

• –65°C to +150°C

B2-48

MHD SERIES

20 WATT

Output Voltage Temperature Coefficient

• 100 ppm/°C typical

Input to Output Capacitance

• 50 pF typical

Current Limit

• 115% of full load typical

Isolation

• 100 megohm minimum at 500 V

Audio Rejection

• 50 dB typical

Conversion Frequency

• Free run mode 625 kHz typical

550 kHz. min, 650 kHz max

• External sync range 500 to 675 kHz

Inhibit Pin Voltage (unit enabled)

• 9 to 11 V

Input Voltage Range

• 16 to 40 VDC continuous

• 50 V for up to 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, 0.0 V min

• Logic high 4.0 V min, 10 V max

• Referenced to input common

• If not used, connect to input common

Inhibit: TTL Open Collector

• Logic low (output disabled)

Logic low voltage

≤0.8 V

Inhibit pin current 8.0 mA max

• Referenced to input common

• Logic high (output enabled)

Open collector

SINGLE OUTPUT MODELS

MHD2805S

MHD2812S

MHD2815S

MHD2818S

PARAMETER

CONDITION

MIN

TYP MAX

MIN

TYP MAX

MIN

TYP MAX

MIN

TYP MAX

UNITS

OUTPUT VOLTAGE

4.95

5.00

5.05

11.88 12.00 12.12

14.85 15.00 15.15

17.82 18.00 18.18

VDC

0

—

3

0

—

1.67

0

—

1.33

0

—

1.11

A

0

—

15

0

—

20

0

—

20

0

—

20

W

OUTPUT RIPPLE

10 kHz – 2 MHz

—

35

50

—

25

40

—

25

40

—

—

40

mV p

VOLTAGE

Tc = –55°C TO +125°C

—

50

90

—

40

90

—

40

90

—

—

90

Vin = 16 to 40 VDC

—

10

50

—

10

50

—

10

50

—

—

50

mV

Tc = –55°C TO +125°C

—

15

50

—

15

50

—

15

50

—

—

50

LOAD REGULATION

NO LOAD TO FULL

—

5

50

—

5

50

—

5

50

—

—

50

mV

Tc = –55°C TO +125°C

—

15

50

—

15

50

—

15

50

—

—

50

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

INPUT CURRENT

—

35

75

—

35

75

—

35

75

—

—

75

mA

FULL LOAD

—

0.70

—

—

0.87

—

—

0.85

—

—

—

—

A

—7

8

—

7

8

—

7

8

—

—

8

mA

INPUT RIPPLE

10 kHz – 10 MHz

CURRENT

Tc = –55°C TO +125°C

—

20

50

—

20

50

—

20

50

—

—

50

mA p-p

EFFICIENCY

76

78

—

80

83

—

81

84

—

81

—

—

%

SHORT CIRCUIT

SHORT CIRCUIT TO

POWER DISSIPATION

—

—

10

—

—

10

—

—

10

—

—

10

A

FULL LOAD

—

1.4

5

—

1.4

5

—

1.4

5

—

—

5

ms

STEP LOAD RESP.

50% – 100% – 50%

—

±200 ±300

—

±250 ±400

—

±350 ±500

—

—

±600

TRANSIENT

10% – 100%

—

–400 –600

—

–600 –1000

—

–800 –1200

—

—

—

mV pk

100% – 10%

—

+350 +600

—

+500 +750

—

+600 +1000

—

—

—

50% – 100% – 50%

—

60

200

—

60

200

—

60

200

—

—

200

10% – 100%

—

60

600

—

150

300

—

250

500

—

—

—

µs

100% – 10%

—

200

600

—

250

500

—

250

500

—

—

—

STEP LINE RESP.

16 – 40 – 16 VDC

—

±200 ±300

—

±400 ±500

—

±500 ±600

—

—

±600

mV pk

—

—

300

—

—

300

—

—

300

—

—

300

µs

DELAY

—

1.4

5

—

1.4

5

—

1.4

5

—

—

5

ms

OVERSHOOT

FULL LOAD

—

0

50

—

0

120

—

0

150

—

—

180

mV pk

NO LOAD

—

50

250

—

120

600

—

150

750

—

—

—

Electrical Characteristics:25C Tc, 28 VDC Vin, 100% load, free run, unless otherwise specified.

Notes

1. Tc = –55°C to +125°C

2. Operation is limited below 16V (see Figure 15).

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

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

Vout is within 1% of final value.

5. Transition time

≥ 10 µs.