DCP02 Series
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SBVS011C–MARCH 2000–REVISED DECEMBER 2005
ADDITIONAL FUNCTIONS
Connecting the DCP02 in Series
DISABLE/ENABLE
Multiple DCP02 isolated 2W DC/DC converters can
be connected in series to provide nonstandard
voltage rails. This is possible by using the floating
outputs provided by the galvanic isolation of the
DCP02.
The DCP02 can be disabled or enabled by driving the
SYNC pin using an open drain CMOS gate. If the
SYNC pin is pulled low, the DCP02 will be disabled.
The disable time depends upon the external loading;
the internal disable function is implemented in 2µs.
Removal of the pull down will cause the DCP02 to be
enabled.
Connect the positive VOUT from one DCP02 to the
negative VOUT (0V) of another (see Figure 7). If the
SYNC pins are tied together, the self-synchronization
feature of the DCP02 will prevent beat frequencies on
the voltage rails. The SYNC feature of the DCP02
allows easy series connection without external
filtering, thus minimizing cost.
Capacitive loading on the SYNC pin should be
minimized in order to prevent a reduction in the
oscillator frequency.
DECOUPLING
The outputs on the dual-output DCP02 versions can
also be connected in series to provide two times the
magnitude of VOUT, as shown in Figure 8. For
Ripple Reduction
The high switching frequency of 400kHz allows
simple filtering. To reduce ripple, it is recommended
that a 1µF capacitor be used on VOUT. Dual outputs
should both be decoupled to pin 5. A 2.2µF capacitor
on the input is recommended.
example,
a dual 15V DCP022415D could be
connected to provide a 30V rail.
Connecting the DCP02 in Parallel
If the output power from one DCP02 is not sufficient,
it is possible to parallel the outputs of multiple
DCP02s, as shown in Figure 9. Again, the SYNC
feature allows easy synchronization to prevent
power-rail beat frequencies at no additional filtering
cost.
V
+V
SUPPLY
V
+V
OUT
S
OUT
OUT
0V
-V
DCP
02
-V
OUT
0V
COM
Figure 8. Connecting Dual Outputs in Series
V
V
V
SUPPLY
OUT
S
SYNC
DCP
02
0V
0V
2 x Power Out
V
V
OUT
S
SYNC
DCP
02
0V
0V
COM
Figure 9. Connecting Multiple DCP02s in Parallel
7
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