VT048A480T006TP - Vicor Corporation

Voltage Transformation Module VT048A480T006FP vicorpower.com Rev. 1.0 Page 1 of 11

Product Grade Temperatures (°C)

Grade Operating Storage

T = -40 to +100 -40 to +125

M = -55 to +100 -65 to +125

Baseplate

F= Slotted flange

T= Transverse heat sink[a]

[a] Contact factory

VTMTM Current Multiplier

Product Overview

The thermally enhanced VI BRICK VTM current multiplier excels at speed, density and

efficiency to meet the demands of advanced power applications. Combined with the

VI BRICK PRM regulator they create a DC-DC converter with flexibility to provide isolation

and regulation where needed. The PRM can be located with the VTM at the point of load

or remotely in the back plane or on a daughter card.

Applications

•Solid state lighting

•Stadium displays

•Industrial controls

•Avionics

•Underseas

•RF Amplifiers

•Microprocessor and DSP

requiring fast response

•100°C baseplate operation

•48 V to 48 V Converter

•6.3 A (9.4 A for 1 ms)

•High density – up to 390 W/in3

•Small footprint – 1.64 and 2.08 in2

•Height above board – 0.37 in (9.5 mm)

•Low weight – 1.10 oz (31.3 g)

•ZVS / ZCS isolated sine amplitude converter

•

Typical efficiency 96%

•<1 µs transient response

•Isolated output

•No output filtering required

•Lead free wave solder compatible

•Agency approvals

Features

VT 048 A 480 T 006 F P

Output

Voltage

Designator

(=VOUT x10)

Output

Current

Designator

(=IOUT)

Part Numbering

Voltage

Transformation

Module

Input

Voltage

Designator

Package

Size

Pin Style

P = Through hole

Size:

1.91 x 1.09 x 0.37 in

48,6 x 27,7 x 9,5 mm

Voltage Transformation Module VT048A480T006FP vicorpower.com Rev. 1.0 Page 2 of 11

Parameter Values Unit Notes

+In to -In -1.0 to 60 Vdc

+In to -In 100 Vdc For 100 ms

PC to -In -0.3 to 7.0 Vdc

VC to -In -0.3 to 19.0 Vdc

+Out to -Out -0.5 to 60.0 Vdc

Isolation voltage 2,250 Vdc Input to output

Output current 6.3 A Continuous

Peak output current 9.4 A For 1 ms

Output power 336 W Continuous

Peak output power 504 W For 1 ms

Operating temperature -40 to +100 °C T-Grade; baseplate

-55 to +100 °C M-Grade; baseplate

Storage temperature -40 to +125 °C T-Grade

-65 to +125 °C M-Grade

Electrical characteristics apply over the full operating range of input voltage, output load (resistive) and baseplate temperature,

unless otherwise specified. All temperatures refer to the operating temperature at the center of the baseplate.

Absolute Maximum Ratings

SPECIFICATIONS

Parameter Min Typ Max Unit Notes

Input voltage range 26.0 48 55 Vdc Max VIN = 53 V, operating from -55°C to -40°C

Input dV/dt 1 V/µs

Input overvoltage turn-on 55.0 Vdc

Input overvoltage turn-off 59.5 Vdc

Input current 6.7 Adc

Input reflected ripple current 143 mA p-p Using test circuit in Figure 10; See Figure 1

No load power dissipation 2.8 4.6 W

Internal input capacitance 4.0 µF

Internal input inductance 5 nH

Input Specifications (Conditions are at 48 Vin, full load, and 25°C ambient unless otherwise specified)

Note: Stresses in excess of the maximum ratings can cause permanent damage to the device. Operation of the device is not implied at these or any other conditions

in excess of those given in the specification. Exposure to absolute maximum ratings can adversely affect device reliability.

Voltage Transformation Module VT048A480T006FP vicorpower.com Rev. 1.0 Page 3 of 11

SPECIFICATIONS (CONT.)

WAVEFORMS

Figure 1 — Input reflected ripple current at full load and 48 Vf.

Ripple vs. Output Current

100

125

150

175

200

0 0.625 1.25 1.875 2.5 3.125 3.75 4.375 5 5.625 6.25

Output Current (A)

Output Ripple (mVpk-pk)

Figure 2 — Output voltage ripple vs. output current at 48 Vf with no POL

bypass capacitance.

Parameter Min Typ Max Unit Note

Output voltage 26.0 55.0 Vdc No load

24.7 53.8 Vdc Full load

Rated DC current 0 6.3 Adc 26.0 - 55 VIN

Peak repetitive current 9.4 A Max pulse width 1ms, max duty cycle 10%,

baseline power 50%

Short circuit protection set point 6.4 Adc Module will shut down

Current share accuracy 5 10 % See Parallel Operation on Page 7

Efficiency

Half load 96.0 96.7 % See Figure 3

Full load 96.0 96.4 % See Figure 3

Internal output inductance 6.0 nH

Internal output capacitance 6 µF Effective value

Output overvoltage setpoint 55.0 Vdc Module will shut down

Output ripple voltage

No external bypass 180 320 mVp-p See Figures 2 and 5

9.4 µF bypass capacitor 20 mVp-p See Figure 6

Effective switching frequency 3.2 3.3 3.50 MHz Fixed, 1.7 MHz per phase

Line regulation

K 0.9900 1 1.0100 VOUT = K•VIN at no load

Load regulation

ROUT 188 210 mΩSee Figure 13

Transient response

Voltage overshoot 1.2 V 6.3 A load step with 100 µF CIN; See Figures 7 and 8

Response time 200 ns See Figures 7 and 8

Recovery time 1 µs See Figures 7 and 8

Output Specifications (Conditions are at 48 Vin, full load, and 25°C ambient unless otherwise specified)

Voltage Transformation Module VT048A480T006FP vicorpower.com Rev. 1.0 Page 4 of 11

Figure 8 — 6.3-0 A load step with 100 µF input capacitance and no output

capacitance.

Figure 7 — 0-6.3 A load step with 100 µF input capacitance and no output

capacitance.

SPECIFICATIONS (CONT.)

Figure 5 — Output voltage ripple at full load and 48 Vf with no POL bypass

capacitance.

Figure 6 — Output voltage ripple at full load and 48 Vf with 9.4 µF ceramic

POL bypass capacitance and 20 nH distribution inductance.

WAVEFORMS

Efficiency vs. Output Current

00.625 1.25 1.875 2.5 3.125 3.75 4.375 5 5.625 6.25

Output Current (A)

Efficiency (%)

Figure 3 — Efficiency vs. output current.

Power Dissipation

0 0.625 1.25 1.875 2.5 3.125 3.75 4.375 5 5.625 6.25

Output Current (A)

Power Dissipation (W)

Figure 4 — Power dissipation vs. output current.

Voltage Transformation Module VT048A480T006FP vicorpower.com Rev. 1.0 Page 5 of 11

SPECIFICATIONS (CONT.)

Parameter Min Typ Max Unit Notes

MTBF

MIL-HDBK-217F 3.5 Mhrs 25°C, GB

Isolation specifications

Voltage 2,250 Vdc Input to output

Capacitance 3,000 pF Input to output

Resistance 10 MΩInput to output

Agency approvals

cTÜVus UL/CSA 60950-1, EN 60950-1

CE Mark Low voltage directive

RoHS

Mechanical See Mechanical Drawings, Figures 15, 16

Weight 1.10/31.3 oz /g

Dimensions

Length 1.91/48,6 in /mm Baseplate model

Width 1.09/27,7 in /mm Baseplate model

Height 0.37/9,5 in /mm Baseplate model

Thermal

Over temperature shutdown 125 130 135 °C Junction temperature

Thermal capacity 23.8 Ws /°C

Baseplate-to-ambient 7.7 °C /W

Baseplate-to-ambient; 1000 LFM 2.9 °C /W

Baseplate-to-sink; flat, greased surface 0.40 °C /W

Baseplate-to-sink; thermal pad 0.36 °C /W

General Specifications

Parameter Min Typ Max Unit Notes

Primary Control (PC)

DC voltage 4.8 5.0 5.2 Vdc

Module disable voltage 2.4 2.5 Vdc

Module enable voltage 2.5 2.6 Vdc VC voltage must be applied when module is

enabled using PC

Current limit 2.4 2.5 2.9 mA Source only

Disable delay time 40 µs PC low to Vout low

VTM Control (VC)

External boost voltage 12 14 19 Vdc Required for VTM start up without PRM

External boost duration 10 ms Vin > 26.0 Vdc. VC must be applied continuously

if Vin < 26.0 Vdc.

Auxiliary Pins

Voltage Transformation Module VT048A480T006FP vicorpower.com Rev. 1.0 Page 6 of 11

+In / -In DC Voltage Ports

The VTM input should not exceed the maximum specified. Be aware of this

limit in applications where the VTM is being driven above its nominal out-

put voltage. If less than 26 Vdc is present at the +In and -In ports, a contin-

uous VC voltage must be applied for the VTM to process power. Otherwise

VC voltage need only be applied for 10 ms after the voltage at the +In and

-In ports has reached or exceeded 26 Vdc. If the input voltage exceeds the

overvoltage turn-off, the VTM will shutdown. The VTM 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, synchronizing the output rise of the VTM with the output

rise of the PRM. Additionally, the VC port provides feedback to the PRM to

compensate for the VTM output resistance. In typical applications using

VTMs powered from PRMs, the PRM’s VC port should be connected to the

VTM VC port.

In applications where a VTM is being used without a PRM, 14 V must be

supplied to the VC port for as long as the input voltage is below 26 V and

for 10 ms after the input voltage has reached or exceeded 26 V. The VTM is

not designed for extended operation below 26 V. The VC port should only be

used to provide VCC voltage to the VTM during startup.

PC – Primary Control

The Primary Control (PC) port is a multifunction port for controlling the

VTM as follows:

Disable – If PC is left floating, the VTM 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.

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 13 defines

the output voltage of the VTM. The current source capability of the VTM is

shown in the specification table.

To take full advantage of the VTM, the user should note the low output

impedance of the device. The low output impedance provides fast tran-

sient 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.

PIN / CONTROL FUNCTIONS

Figure 9 — VI BRICK VTM pin configuration (viewed from pin side)

Voltage Transformation Module VT048A480T006FP vicorpower.com Rev. 1.0 Page 7 of 11

APPLICATION NOTES & TEST CIRCUIT

Parallel Operation

In applications requiring higher current or redundancy, VTMs can be

operated in parallel without adding control circuitry or signal lines. To

maximize current sharing accuracy, it is imperative that the source and

load impedance on each VTM in a parallel array be equal. If VTMs are

being fed by an upstream PRM, the VC nodes of all VTMs must be con-

nected to the PRM VC.

To achieve matched impedances, dedicated power planes within the PC

board should be used for the output and output return paths to the

array of paralleled VTMs. This technique is preferable to using traces of

varying size and length.

The VTM power train and control architecture allow bi-directional power

transfer when the VTM is operating within its specified ranges. Bi-direc-

tional power processing improves transient response in the event of an

output load dump. The VTM may operate in reverse, returning output

power back to the input source. It does so efficiently.

Input Impedance Recommendations

To take full advantage of the VTM’s capabilities, the impedance of the

source (input source plus the PC board impedance) must be low over a

range from DC to 5 MHz. The input of the VTM (factorized bus) should

be locally bypassed with a 8 µF low Q aluminum electrolytic capacitor.

Additional input capacitance may be added to improve transient

performance or compensate for high source impedance. The VTM has

extremely wide bandwidth so the source response to transients is usually

the limiting factor in overall output response of the VTM.

Anomalies in the response of the source will appear at the output of the

VTM, multiplied by its K factor of1 . The DC resistance of the source

should be kept as low as possible to minimize voltage deviations on the

input to the VTM. If the VTM is going to be operating close to the high

limit of its input range, make sure input voltage deviations will not trig-

ger the input overvoltage turn-off threshold.

Input Fuse Recommendations

VI BRICKs are not internally fused in order to provide flexibility in config-

uring power systems. However, input line fusing of VI BRICKs must

always be incorporated within the power system. A fast acting fuse is

required to meet safety agency Conditions of Acceptability. The input

line fuse should be placed in series with the +In port. For agency

approvals and fusing conditions, click on the link below:

http://www.vicorpower.com/technical_library/technical_documentation/quality_

and_certification/safety_approvals/

Application Notes

For VTM and VI BRICK application notes on soldering, board layout, and

system design please click on the link below:

http://www.vicorpower.com/technical_library/application_information/

Applications Assistance

Please contact Vicor Applications Engineering for assistance,

1-800-927-9474, or email at apps@vicorpower.com.

Load

–

Input reflected ripple

measurement point

0.47 μF

ceramic +

–

14 V

VTM

+IN +OUT

-OUT

+OUT

-OUT

-IN

Figure 10 — VI BRICK VTM test circuit

Notes:

1. C3 should be placed close to the load

2. R3 may be ESR of C3 or a separate damping resistor.

[a] See Input Fuse Recommendations section

9.4 µF

5mΩ

47 µF

Al electrolytic

10 A[a]

Fuse

Voltage Transformation Module VT048A480T006FP vicorpower.com Rev. 1.0 Page 8 of 11

APPLICATION NOTES (CONT.)

Figure 11 — The PRM controls the factorized bus voltage, Vf, in proportion to output current to compensate for the output resistance, Ro, of the VTM. The VTM

output voltage is typically within 1% of the desired load voltage (VL) over all line and load conditions.

Factorized

Bus (Vf)

Vo = VL ± 1.0%

(Io•Ro)

Vf = VL +

Vin

ROS

RCD

VTM

+IN +OUT

-OUT

+OUT

-OUT

-IN

PRM-AL

+IN +OUT

-OUT

-IN

FPA ADAPTIVE LOOP

Figure 12 — An external error amplifier or Point-of-Load IC (POLIC) senses the load voltage and controls the PRM output – the Factorized Bus – as a function of

output current, compensating for the output resistance of the VTM and for distribution resistance.

Remote

Loop

Control

Vf = f (Vs)

Factorized

Power Bus

Vo = VL ± 0.4%

–S

Vin

VTM

+IN +OUT

-OUT

+OUT

-OUT

-IN

PRM-AL

+IN +OUT

-OUT

-IN

FPA NON-ISOLATED REMOTE LOOP

In figures below;

K = VTM transformation ratio Vf= PRM output (Factorized Bus Voltage)

RO= VTM output resistance VO= VTM output

VL= Desired load voltage

Voltage Transformation Module VT048A480T006FP vicorpower.com Rev. 1.0 Page 9 of 11

BEHAVIORAL MODELS

VI BRICK VTM LEVEL 1 DC BEHAVIORAL MODEL FOR 48 V TO 48 V, 6.3 A

VI BRICK VTM LEVEL 2 TRANSIENT BEHAVIORAL MODEL FOR 48 V TO 48 V, 6.3 A

–

VOUT

VIN

V•I

–

IOUT ROUT

–

Figure 13 —This model characterizes the DC operation of the VI BRICK VTM, including the converter transfer function and its losses. The model enables estimates

or simulations of output voltage as a function of input voltage and output load, as well as total converter power dissipation or heat generation.

LIN = 5 nH

–

VOUT

COUT

VIN

V•I

–

CIN

IOUT

RCOUT

ROUT

RCIN

Figure 14 —This model characterizes the AC operation of the VI BRICK VTM including response to output load or input voltage transients or steady state

modulations. The model enables estimates or simulations of input and output voltages under transient conditions, including response to a stepped load

with or without external filtering elements.

188.0 mΩ

1• Vin

1 • Iout

58 mA

1 • Iout 1 • Vin

188.0 mΩ

RCIN

1.3 mΩ

14.8 nH

47.1 mΩRCOUT

0.87 mΩ

6µF

LOUT = 1.6 nH

4.0 µF

Voltage Transformation Module VT048A480T006FP vicorpower.com Rev. 1.0 Page 10 of 11

Figure 15 — Module outline

Figure 16 — PCB mounting specifications

MECHANICAL DRAWINGS

Recommended PCB Pattern

(Component side shown)

Baseplate - Slotted Flange Heat Sink (Transverse)

Voltage Transformation Module VT048A480T006FP vicorpower.com Rev. 1.0 3/08

Vicor Corporation

25 Frontage Road

Andover, MA, USA 01810

Tel: 800-735-6200

Fax: 978-475-6715

Customer Service: custserv@vicorpower.com

Technical Support: apps@vicorpower.com

Warranty

Vicor products are guaranteed for two years from date of shipment against defects in material or workmanship when in

normal use and service. This warranty does not extend to products subjected to misuse, accident, or improper application

or maintenance. Vicor shall not be liable for collateral or consequential damage. This warranty is extended to the original

purchaser only.

EXCEPT FOR THE FOREGOING EXPRESS WARRANTY, VICOR MAKES NO WARRANTY, EXPRESS OR IMPLIED, INCLUDING,

BUT NOT LIMITED TO, THE WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.

Vicor will repair or replace defective products in accordance with its own best judgement. For service under this warranty,

the buyer must contact Vicor to obtain a Return Material Authorization (RMA) number and shipping instructions. Products

returned without prior authorization will be returned to the buyer. The buyer will pay all charges incurred in returning

the product to the factory. Vicor will pay all reshipment charges if the product was defective within the terms of this

warranty.

Information published by Vicor has been carefully checked and is believed to be accurate; however, no responsibility is

assumed for inaccuracies. Vicor reserves the right to make changes to any products without further notice to improve

reliability, function, or design. Vicor does not assume any liability arising out of the application or use of any product or

circuit; neither does it convey any license under its patent rights nor the rights of others. Vicor general policy does not

recommend the use of its components in life support applications wherein a failure or malfunction may directly threaten

life or injury. Per Vicor Terms and Conditions of Sale, the user of Vicor components in life support applications assumes

all risks of such use and indemnifies Vicor against all damages.

Vicor’s comprehensive line of power solutions includes high density AC-DC and

DC-DC modules and accessory components, fully configurable AC-DC and DC-DC

power supplies, and complete custom power systems.

Information furnished by Vicor is believed to be accurate and reliable. However, no responsibility is assumed by Vicor for

its use. Vicor components are not designed to be used in applications, such as life support systems, wherein a failure or

malfunction could result in injury or death. All sales are subject to Vicor’s Terms and Conditions of Sale, which are available

upon request.

Specifications are subject to change without notice.

Intellectual Property Notice

Vicor and its subsidiaries own Intellectual Property (including issued U.S. and Foreign Patents and pending patent

applications) relating to the products described in this data sheet. Interested parties should contact Vicor's Intel-

lectual Property Department.

The products described on this data sheet are protected by the following U.S. Patents Numbers:

5,945,130; 6,403,009; 6,710,257; 6,911,848; 6,930,893; 6,934,166; 6,940,013; 6,969,909; 7,038,917;

7,145,186; 7,166,898; 7,187,263; 7,202,646; 7,361,844; D496,906; D505,114; D506,438; D509,472; and for

use under U.S. Pat. Nos. 6,975,098 and 6,984,965.