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V048F480T006 Datasheet, PDF (5/11 Pages) Vicor Corporation – VTM Current Multiplier
Pin / Control Functions
+In / -In DC Voltage Ports
The VTM™ current multiplier input should be connected to the
PRM™ regulator output terminals. Given that both the regulator and
current multiplier have high switching frequencies, it is often good
practice to use a series inductor to limit high frequency currents
between the PRM module output and VTM module input capacitors.
The input voltage should not exceed the maximum specified. If the
input voltage exceeds the overvoltage turn-off, the VTM module will
shutdown. The VTM module does not have internal input reverse
polarity protection. Adding a properly sized diode in series with the
positive input or a fused reverse-shunt diode will provide reverse polarity
protection.
TM – For Factory Use Only
VC – VTM Control
The VC port is multiplexed. It receives the initial VCC voltage from an
upstream PRM regulator, synchronizing the output rise of the VTM
module with the output rise of the regulator. Additionally, the VC port
provides feedback to the PRM to compensate for the current multiplier
output resistance. In typical applications using VTM modules powered
from PRM regulators, the regulators VC port should be connected to
the VTM module VC port.
The VC port is not intended to be used to supply VCC voltage to the
VTM module for extended periods of time. If VC is being supplied from
a source other than the PRM regulators, the voltage should be removed
after 20 ms.
PC – Primary Control
The Primary Control (PC) port is a multifunction port for controlling the
current multiplier as follows:
Disable – If PC is left floating, the VTM module output is enabled.
To disable the output, the PC port must be pulled lower than 2.4 V,
referenced to -In. Optocouplers, open collector transistors or relays
can be used to control the PC port. Once disabled, 14 V must be
re-applied to the VC port to restart the VTM module.
Primary Auxiliary Supply – The PC port can source up to 2.4 mA
at 5 Vdc.
+Out / -Out DC Voltage Output Ports
The output and output return are through two sets of contact
locations. The respective +Out and –Out groups must be connected in
parallel with as low an interconnect resistance as possible. Within the
specified input voltage range, the Level 1 DC behavioral model shown
in Figure 16 defines the output voltage of the VTM module. The
current source capability of the VTM module is shown in the
specification table.
To take full advantage of the VTM current multiplier, the user should
note the low output impedance of the device. The low output
impedance provides fast transient response without the need for bulk
POL capacitance. Limited-life electrolytic capacitors required with
conventional converters can be reduced or even eliminated, saving cost
and valuable board real estate.
vicorpower.com 800-735-6200
+Out
-Out
+Out
-Out
43
A
B
C
D
E
F
G
H
J
K
L
M
N
P
R
T
21
A
B
C
+In
D
E
TM
H
J
VC
K
PC
L
M
N
P
-In
R
T
Bottom View
Signal Name
+In
–In
TM
VC
PC
+Out
–Out
Pin Designation
A1-E1, A2-E2
L1-T1, L2-T2
H1, H2
J1, J2
K1, K2
A3-D3, A4-D4,
J3-M3, J4-M4
E3-H3, E4-H4,
N3-T3, N4-T4
Figure 9 — VTM™ current multiplier pin configuration
VTM™ Current Multiplier
V048F480T006
Rev. 3.1
Page 5 of 11