MHD SERIES
20 WATT
DC/DC CONVERTERS
ABSOLUTE MAXIMUM RATINGS
TYPICAL CHARACTERISTICS
Output Voltage Temperature Coefficient
• 100 ppm/°C typical
Input to Output Capacitance
• 50 pF typical
Current Limit
• 115% of full load typical
Isolation
SYNC AND INHIBIT
Sync (500 to 675 kHz)
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
• 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
• 100 megohm minimum at 500 V
Audio Rejection
Inhibit pin current 8.0 mA max
• 50 dB typical
RECOMMENDED OPERATING CONDITIONS
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
• Referenced to input common
• Logic high (output enabled)
Open collector
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
• –55°C to +135°C Absolute
Derating Output Power/Current
• Linearly from 100% at 125°C to 0% at 135° C
Electrical Characteristics:25C Tc, 28 VDC Vin, 100% load, free run, unless otherwise specified.
SINGLE OUTPUT MODELS
PARAMETER
MHD2805S
MHD2812S
MHD2815S
MHD2818S
CONDITION
MIN TYP MAX
MIN TYP MAX
MIN TYP MAX
MIN TYP MAX
UNITS
VDC
A
OUTPUT VOLTAGE
1
4.95 5.00 5.05
11.88 12.00 12.12
14.85 15.00 15.15
17.82 18.00 18.18
OUTPUT CURRENT
V
= 16 to 40 VDC
= 16 to 40 VDC
0
0
—
—
3
0
0
—
—
1.67
20
0
0
—
—
1.33
20
0
0
—
—
1.11
20
IN
IN
1
OUTPUT POWER
V
15
W
OUTPUT RIPPLE
VOLTAGE
10 kHz – 2 MHz
—
—
—
—
—
—
16
—
35
50
10
15
5
50
90
50
50
50
50
40
50
—
—
—
—
—
—
16
—
25
40
10
15
5
40
90
50
50
50
50
40
50
—
—
—
—
—
—
16
—
25
40
10
15
5
40
90
50
50
50
50
40
50
—
—
—
—
—
—
16
—
—
—
—
—
—
—
28
—
40
90
50
50
50
50
40
50
mV p
Tc = –55°C TO +125°C
Vin = 16 to 40 VDC
Tc = –55°C TO +125°C
NO LOAD TO FULL
Tc = –55°C TO +125°C
CONTINUOUS
2
LINE REGULATION
mV
mV
LOAD REGULATION
15
28
—
15
28
—
15
28
—
1
INPUT VOLTAGE
VDC
V
NO LOAD TO FULL
INPUT CURRENT
TRANSIENT 50 ms
1
NO LOAD
—
—
—
35
0.70
7
75
—
8
—
—
—
35
0.87
7
75
—
8
—
—
—
35
0.85
7
75
—
8
—
—
—
—
—
—
75
—
8
mA
A
FULL LOAD
1
INHIBITED
mA
INPUT RIPPLE
CURRENT
10 kHz – 10 MHz
Tc = –55°C TO +125°C
—
20
78
50
—
—
20
83
50
—
—
20
84
50
—
—
—
—
50
—
mA p-p
%
EFFICIENCY
76
80
81
81
3
LOAD FAULT
SHORT CIRCUIT
SHORT CIRCUIT TO
FULL LOAD
POWER DISSIPATION
—
—
—
—
—
—
—
—
—
10
5
—
—
—
—
—
—
—
—
—
10
5
—
—
—
—
—
—
—
—
—
10
5
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
10
5
A
1, 3
RECOVERY
1.4
1.4
1.4
ms
STEP LOAD RESP.
TRANSIENT
50% – 100% – 50%
10% – 100%
±200 ±300
–400 –600
+350 +600
±250 ±400
–600 –1000
+500 +750
±350 ±500
–800 –1200
+600 +1000
±600
—
mV pk
µs
100% – 10%
—
50% – 100% – 50%
10% – 100%
60
60
200
600
60
200
60
200
200
—
4
RECOVERY
150 300
250 500
250 500
250 500
100% – 10%
200 600
—
STEP LINE RESP.
16 – 40 – 16 VDC
5
TRANSIENT
—
—
±200 ±300
—
—
±400 ±500
—
—
±500 ±600
—
—
—
—
±600
300
mV pk
µs
4
RECOVERY
—
300
5
—
300
5
—
300
5
1
START-UP
DELAY
—
1.4
—
1.4
—
1.4
—
—
5
ms
OVERSHOOT
FULL LOAD
NO LOAD
—
—
0
50
—
—
0
120
—
—
0
150
—
—
—
—
180
—
mV pk
50
250
120 600
150 750
Notes
1. Tc = –55°C to +125°C
2. Operation is limited below 16V (see Figure 15).
4. Recovery time is measured from application of the transient to point at which
Vout is within 1% of final value.
3. Indefinite short circuit protection not guaranteed above 125°C case.
5. Transition time ≥ 10 µs.
B2-48
CRANE [ Crane Aerospace & Electronics. ]
