OPERATING INSTRUCTIONS
Output Filter
The output ripple voltage can be reduced by an external filter to less then 5 mV
pp
. Recommended values:
•
C1, C2: Low ESR capacitor, e.g., OS-CON 100 – 470 µF
•
L1, L2: Choke 1 – 2.2 µH with appropriate rated current, e.g., Coiltronics
®
HC2LP 1 µH /33 A or 2.2 µH /24 A.
Output filter reducing the output ripple of Vo1 and Vo2
Auxiliary Functions
Inhibit and Enable
The inhibit input enables (logic high) or disables (logic low, pull down) all outputs, if a logic signal (TTL, CMOS) is applied. In
systems consisting of several converters this feature may be used to control the activation sequence of the converters by
means of logic signals, or to enable the source to start-up, before full load is applied.
Note:
If this function is not used, the inhibit pin 39 can be left open-circuit (not connected). If pin 39 is connected to a return pin (e.g., pin 22),
the internal logic will disable all outputs. The inhibit input is protected by a decoupling diode.
Characteristics
Conditions
min
typ
max
Unit
V
o
= off
–
2
0.8
V
V
inh
inhibit
voltage
V
o
= on
V
i min
–
V
i max
I
o
= 0 –
I
o max
2.4
50
t
r
Rise time
120
ms
t
f
Fall time
depending on
I
o
Inhibit and enable inputs
Typical output response as a function of inhibit voltage
The enable pin 27 (EN#) must be connected to a return pin (e.g., pin 22) enable the converter. Pin 27 is shorter than the
others ensuring startup only, when all other pins are already connected to the system providing true hot-swap capability.
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