DFC15 SERIES – DUAL OUTPUT
DFC15 SERIES BLOCK DIAGRAM
OUTPUT POWER DERATING
ISOLATION TRANSFORMER
15
THERMAL SHUTDOWN
+
+
+ INPUT
4
5
6
+ OUTPUT
POWER OUTPUT
CMN
10
1
– INPUT
2
LC
INPUT
FILTER
CURRENT
MODE
PWM
– OUTPUT
+
ON/OFF
7
TRIM
5
3
ISOLATED
FEEDBACK
–
FIVE SIDED SHIELDED COPPER CASE
LOW TC
BANDGAP
REFERENCE
0
40
60
70
80
50
AMBIENT TEMPERATURE
90
APPLICATION NOTES (cont’d):
Remote ON/OFF Operation
The remote ON/OFF pin may be left
floating if this function is not used. It is
recommended to drive this pin with an
open collector arrangement or a relay
contact. When the ON/OFF pin is pulled
low with respect to the -INPUT, the
converter is placed in a low power drain
state. Do not drive this input from a logic
gate directly; there is a 100K internal
pull-up resistor to a 9 volt source.
Output TRIM
The TRIM pin may be used to adjust the
output +5% to -34% from the nominal
setting. This function allows adjustment for
voltage drops in the system wiring. As well
5.2 volt Figure 1 shows the proper
connections to use this function. A trimpot
value of 10K or a fixed resistor may be
used. If the TRIM function is not required
the pin may be left floating.
Typical Performance: (Tc=25°C, Vin=Nom VDC, Rated Load)
EFFICIENCY Vs. LINE INPUT VOLTAGE (12V OUTPUT)
REFLECTED RMS RIPPLE (AMPS)
90
1.0
100% FULL LOAD
0.8
0.6
0.4
50% FULL LOAD
0.2
0.0
20 24 28 32 36 40 44 48 52 56 60 64 68 72
INPUT RIPPLE Vs. LINE INPUT (12V OUTPUT)
EFFICIENCY (%)
50% FULL LOAD
85
75% FULL LOAD
80
100% FULL LOAD
75
20 24 28 32 36 40 44 48 52 56 60 64 68 72
LINE INPUT (VOLTS)
LINE INPUT (VOLTS)
INPUT CURRENT Vs. LINE INPUT (12V OUTPUT)
1.2
OUTPUT VOLTAGE Vs. OUTPUT LOAD (12V OUTPUT)
120
INPUT CURRENT (AMPS)
0.9
100% FULL LOAD
0.6
OUTPUT VOLTAGE (%)
56
64
72
100
80
60
40
20
0
0.3
50% FULL LOAD
0.0
0
8
16
24
32
40
48
0
50
100
150
200
250
300
350
400
LINE INPUT (VOLTS)
OUTPUT LOAD (%)
+OUT
4
TRIM
7
-OUT
6
USING TRIMPOT
10K
LOAD
+OUT
4
TRIM
DOWN
TRIM
UP
EFFICIENCY (%)
EFFICIENCY Vs. LOAD (12V OUTPUT)
90
LINE =
20VDC
TRIM
7
-OUT
6
LOAD
80
LINE =
48VDC
70
LINE =
72VDC
USING FIXED RESISTORS
Figure 1.
60
0
10
20
30
40
50
60
70
80
90 100
LOAD (%)
3
POWER-ONE [ POWER-ONE ]
