(5) Operation with AC input
¡
The DHS series handles only for the DC input.
A front end unit(AC/DC unit) is required when the DHS series is
operated with AC input.
(6) Reverse input voltage protection
¡
Avoid the reverse polarity input voltage. It will break the power
supply.
It is possible to protect the unit from the reverse input voltage by
installing an external diode.
(2) Noise fi lter/Decoupling capacitor
¡
Install an external noise filter and a decoupling capacitor C
Y
for
low line-noise and for stable operation of the power supply.
¡
Install a correspondence fi lter, if a noise standard meeting is re-
quired or if the surge voltage may be applied to the unit.
¡
Install a primary decoupling capacitor C
Y
, with more than 470pF,
near the input pins(within 50mm from the pins).
¡
When the total capacitance of the primary decoupling capacitor is
more than 8800pF, the nominal value in the specifi cation may not
be met by the Hi-Pot test between input and output.
In this case, it is that a capacitor should be installed between out-
put and FG.
(3) External capacitor on the Input side.
¡
Install an external capacitor Cin bVIN and -VIN input pins
for low line-noise and for stable operation of the power supply.
DHS50A/100A
: more than 22 F
*
DHS200A
: more than 47 F
*
DHS50B/100B/250B : more than 0.1 F
*
When the line inductance is high or ambient temperature is
lower than -20
C
, please increase Cin value more than the
value indicated above.
¡
When the line impedance is high or the input voltage rise quickly
at start-up(less than 10 s), install a capacitor Cin bVIN
and -VIN input pins(within 50mm from pins).
DHS50B/100B : more than 10 F
DHS250B
: more than 22 F
(4) Input voltage range/Input current range
¡
The specifi cation of input ripple voltage is shown as below.
Ripple voltage DHS50A/100A/200A : less than 10Vp-p
DHS50B/100B/250B : less than 20Vp-p
¡
Make sure that the voltage fl uctuation, including the ripple voltage,
will not exceed the input voltage range.
¡
Use a front end unit with enough power, considering the start-up
current Ip of this unit.
3.2 Wiring output pin
¡
Install an external capacitor Co bVOUT and -VOUT pins
for stable operation of the power supply.
Recommended capacitance of Co is shown in Table 3.2.
¡
Select the high frequency type capacitor. Output ripple and start-
up waveform may be infl uenced by ESR ESL of the capacitor and
the wiring impedance.
¡
Install a capacitor Co near the output pins(within 50mm from the
pins).
¡
The specifi ed ripple and ripple noise are measured by the method
introduced in Fig. 3.5.
Ripple
voltage
Input voltage [V]
Input voltage range
time
t
DC-DC Converters Bus Converter.Power Module Type
Instruction Manual
DHS-17
DHS
Fig.3.1 Input voltage ripple
Fig.3.2 Input current characteristics
+VIN
-VIN
DC IN
+VIN
-VIN
DC IN
(a)
(b)
Fig.3.3 Use with AC input
Table 3.2 Recommended capacitance Co [ F]
lp
Input current [A]
Input voltage [V]
Input voltage range
Fig.3.4 Reverse input voltage protection
DHS50/100 DHS200/250 DHS50/100 DHS200/250
3.3
2200
2200
2200
X
3
2200
X
3
5
2200
2200
2200
X
3
2200
X
3
7.5
-
2200
-
2200
X
3
12
470
1000
470
X
3
1000
X
3
15
470
1000
470
X
3
1000
X
3
24
220
470
220
X
3
470
X
3
28
220
470
220
X
3
470
X
3
48
-
330
-
330
X
3
Tbp=0 +100
Tbp=-40 +100
Output voltage (V)
Model
Temparature of Base plate
AC
/DC
AC
DHS
Load
AC
DHS
Load
DC
DHS
Load
YES
NO
YES
me̲dhs1.indd DHS-17
me dhs1 indd DHS-17
2015/06/19 11:08:04
2015/06/19 11:08:04
