SMHF SERIES
SINGLE AND DUAL
15 WATT
DC/DC C
ONVERTERS
SYNC AND INHIBIT
Sync In (500 to 600 kHz)
• Duty cycle 40% to 60%
• 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)
Logic low voltage
≤0.8
V max
Inhibit pin current 4.0 mA max
• Referenced to input common
• Logic high (output enabled)
Open collector or unconnected
ABSOLUTE MAXIMUM RATINGS
Input Voltage
• 16 to 40 VDC
Power Dissipation (Pd)
• 8W
Output Power
• 12 to 15 watts depending on model
Lead Soldering Temperature (10 sec per lead)
• 300°C
Storage Temperature Range (Case)
• –65°C to +150°C
TYPICAL CHARACTERISTICS
Output Voltage Temperature Coefficient
• 100 ppm /°C typical
• 150 ppm/°C maximum
Input to Output Capacitance
• 60 pF typical
Undervoltage Lockout
• 12 V input typical
Current Limit
• 115% of full load typical
Isolation
• 100 megohm minimum at 500 V
Audio Rejection
• 50 dB typical
Conversion Frequency (º55°C to +125°C Tc)
• Free run 550 kHz typical
480 kHz min, 620 kHz max
Inhibit Pin Voltage (unit enabled)
• 8.5 to 12 V
RECOMMENDED OPERATING CONDITIONS
Input Voltage Range
• 16 to 40 VDC continuous
• 0 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 (Tc)
• Linearly from 100% at 125°C to 0% at 135°C
Electrical Characteristics: 25°C Tc, 28 VDC Vin, 100% load, radiation level O, unless otherwise specified.
SINGLE OUTPUT MODELS
OUTPUT VOLTAGE
Tc = 25°C
OUTPUT CURRENT
V
IN
= 16 TO 40 VDC
OUTPUT POWER
OUTPUT RIPPLE
VOLTAGE
LINE REGULATION
LOAD REGULATION
INPUT VOLTAGE
NO LOAD TO FULL
INPUT CURRENT
V
IN
= 16 TO 40 VDC
10 kHz - 2 MHz
Tc = –55°C TO +125°C
V
IN
= 16 TO 40 VDC
NO LOAD TO FULL
CONTINUOUS
TRANSIENT 120 ms
NO LOAD
FULL LOAD
INHIBITED
10k Hz - 10 MHz
Tc = –55°C TO +125°C
Tc = 25°C
SHORT CIRCUIT
POWER DISSIPATION
RECOVERY
2
50 %–100%– 50%
TRANSIENT
RECOVERY
2
16 TO 40 TO 16 V
IN
TRANSIENT
3
RECOVERY
2
DELAY
OVERSHOOT
4
SMHF283R3S
3.27 3.3 3.33
—
—
2.4
0
—
—
—
—
16
0
—
—
—
—
—
70
—
—
—
60
80
5
20
28
—
25
—
5
45
—
73
5
7.5
8
160
240
100
50
40
50
65
397
12
80
120
—
8
30
500
300
800
1.2
25
300
SMHF2805S
SMHF2812S
SMHF2815S
4.95
5
5.05 11.88 12 12.12 14.85 15 15.15
—
—
2.4
—
—
1.25
—
— 1.00
0
—
—
—
—
16
0
—
—
—
—
—
73
—
—
–500
—
–800
—
—
—
—
30
150
5
20
28
—
25
560
5
35
—
75
3.5
7.5
150
150
550
0.8
10
100
12
80
240
100
50
40
50
40
624
12
80
120
—
8
30
500
300
800
1.2
25
600
0
—
—
—
—
16
0
—
—
—
—
—
78
—
—
—
60
50
5
20
28
—
25
680
5
35
—
79
3.5
7.5
15
160
120
100
50
40
50
50
752
12
80
120
—
8
30
700
500
0
—
—
—
—
16
0
—
—
—
—
—
74
—
—
–800
—
—
60
100
5
20
28
—
25
670
5
35
—
80
3.5
7.5
15
75
260
100
50
40
50
62
752
12
80
120
—
7
30
VDC
A
W
mV p-p
mV
mV
VDC
V
mA
INPUT RIPPLE
CURRENT
EFFICIENCY
LOAD FAULT
1
mA p-p
%
W
ms
mV pk
µs
mV pk
µs
µs
mV pk
STEP LOAD
RESPONSE
STEP LINE
RESPONSE
START-UP
0 TO 28 VIN
–400 150
—
150
–800 550
—
0.8
—
10
—
200
–700 150
—
150
–800 550
—
0.8
—
10
—
200
200 800
600 1200
550 800
0.8 1.2
10
25
200 1500
800 –800
1.2
—
25
—
1200 —
Notes
1. Indefinite short circuit protection not guaranteed above 125°C (case)
2. Recovery time is measured from application of the transient
to the point at which Vout is within regulation.
3. Input step transition time >10µs.
4. Input step transition time <100µs.
34
INTERPOINT [ INTERPOINT CORPORATION COMPANY ]
