Vicor Corporation

Tel: 800-735-6200

V•I Chip Bus Converter

B048K120T10

Rev. 1.2

Page 11 of 16

vicorpower.com

PRELIMINARY

Configuration Options (Cont.)

with 0.25'' Pin Fins

(V•I Chip recessed into PCB)

IN–BOARD MOUNT

11.7

0.46

21.5

0.85

32.0

1.26

Figure 22— In-board with pin fins – package L

ON–BOARD MOUNT

with 0.25'' Pin Fins

22.0

0.87

32.0

1.26

14.0

0.56

Figure 23— On-board with pin fins – package G

mm

in

mm

in

Figure 24—BCM test circuit

F1

+In

PC

SG

TM

–In

Temperature Monitor

+Out

–Out

Load

+

–

1

µF

ceramic

C3

7 A

Fuse

C1

8

µF

ceramic

BCM

R2

2K

Ω

D1

Notes:

Source inductance should be no more than 200 nH. If source inductance is

greater than 200 nH, additional bypass capacitance is required.

C3 should be placed close to the load.

D1 power good indicator will dim when a module fault is detected.

TM should always be referenced to SG.

SW1

Enable/Disable Switch

+

–

0.1

Ω

Input reflected ripple

measurement point

R3

R1

C2

0.47

µF

0.30

Ω

ceramic

Parallel Operation

The BCM will inherently current share when properly

configured in an array of BCMs. Arrays may be used for

higher power or redundancy in an application.

Current sharing accuracy is maximized when the source and

load impedance presented to each BCM within an array are equal.

The recommended method to achieve matched impedances is to

dedicate common copper planes within the PCB to deliver and

return the current to the array, rather than rely upon traces of

varying lengths. In typical applications the current being

delivered to the load is larger than that sourced from the input,

allowing traces to be utilized on the input side if necessary. The

use of dedicated power planes is, however, preferable.

The BCM power train and control architecture allow

bi-directional power transfer, including reverse power

processing from the BCM output to its input. Reverse power

transfer is enabled if the BCM input is within its operating

range and the BCM is otherwise enabled. The BCM’s ability to

process power in reverse improves the BCM transient response

to an output load dump.

Application Note