Vicor VI-J00 Family DC-DC Converters and Configurable Power Supplies - Manual (Page 44)

Design Guide & Applications Manual
For VI-200 and VI-J00 Family DC-DC Converters and Configurable Power Supplies
OVERVIEW
The IAM is a component-level, DC input front-end filter
that when used in conjunction with the Vx-200 and
Vx-J00 Family of DC-DC converters provides a highly
efficient, high density power system with outputs from
1 – 95 Vdc and power expansion from 25 – 800 W.
There are five input attenuator modules available for the
commercial market that comply with telecommunication
and industrial control EMC specifications: Refer to data
sheets for applicable standards at vicorpower.com.
There are two input attenuator modules available for the
defense market that comply with military EMC specifications,
transient specifications and spike specifications. Refer to
product data sheet for applicable standards at
vicorpower.com .
EMC
EMC performance is guaranteed when the IAM is used in
conjunction with the recommended Vicor converters
within the permissible power rating and in accordance
with the recommended installation procedure. (Figure14–3)
The capacitor shown across the input of the converter and
bypass capacitors shown on the –IN and +IN of the DC-DC
converters to ground are required to meet EMC specifications.
The capacitors should be Y-rated (interference suppression).
Y capacitors have high voltage breakdown ratings to meet
the isolation characteristics of the module’s input to
baseplate specification, self-healing properties, and safety
agency approvals.
INPUT REVERSE POLARITY PROTECTION
A Zener diode in the EMC filter provides reverse polarity
protection when used with a properly rated fuse external
to the IAM. The characteristics of the recommended input
line fuses permit normal full load operation with
protection in the event of a reverse polarity by clearing of
the fuse. (Table 4–3).
INPUT TRANSIENT PROTECTION
A Zener diode, inductor and capacitor in the EMC filter
protect against short term transients. Transient voltages
that persist beyond these limits are dropped across an
N-channel enhancement FET, Q1. It is necessary that the
FET be kept in saturation mode during normal operation.
Thus it is necessary to connect the DC-DC converters’
GATE OUT to the IAM’s GATE OUT to charge pump the
10V
U2
U1
OC
OV
Vref
2
Vref 1
+OUT
–OUT
Level
Shift –IN
+IN
–IN
+IN
GATE IN
GATE OUT
PARALLEL
Q1
Q2
EMI Filter
D1
D2
C2
14. Input Attenuator Module (IAM / MI-IAM)
VI-A11-xU 24 V (21 – 32 V) 200 W
VI-AWW-xU 24 V “W” (18 – 36 V) 200 W
VI-A33-xQ 48 V (42 – 60 V) 400 W
VI-ANN-xQ 48 V “N” (36 – 76 V) 400 W
VI-A66-xQ 300 V (200 – 400 V) 400 W
[a] Based on DC-DC converters with 5 V outputs or higher.
Table 14 –1 — Output power capability
Table 14 –2 — Output power capability
Figure 14–1 — Block diagram of Input Attenuator Module (IAM)
Input Maximum Output Power [a]
Model
Voltage Range of Converter Combinations
MI-A22-xU 28 V (16 – 50 V) 200 W
MI-A66-xU 270 V (125 – 400 V) 200 W
Input Maximum Output Power
Model
Voltage Range of Converter Combinations
VI-200 and VI-J00 Family Design Guide Rev 3.5 vicorpower.com
Page 43 of 98
Apps. Eng. 800 927.9474 800 735.6200