PRELIMINARY
Application Note
(continued)
VTM with optional 0.25'' Pin Fins
10
9
8
Tja
7
6
5
4
3
0
100
200
300
400
500
600
Airflow (LFM)
Figure 17—Thermal
resistance
Figure 18—Junction-to-ambient
thermal resistance of VTM with 0.25"
Pin Fins. (Pin Fins are available as a separate item.)
V•I Chip VTM Level 1 DC Behavioral Model for 48 V to 6 V, 40.0 A
I
OUT
R
OUT
5.5 mΩ
1/8 • Iout
+
V
•
I
1/8 • Vin
+
V
IN
I
Q
47 mA
+
–
K
+
V
OUT
–
–
©
–
Figure 19—This
model characterizes the DC operation of the V•I Chip 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.
V•I Chip VTM Level 2 Transient Behavioral Model for 48 V to 6 V, 40.0 A
3.2 nH
L
I
N
= 20 nH
L
IN
= 20 nH
I
OUT
R
OUT
5.5 mΩ
L
OUT
= 1.1 nH
+
C
IN
V
IN
RC
I
N
RC
IN
1.5 mΩ
1/8 • Iout
4.0 µF
V
•
I
10 mΩ
R
RC
OUT
+
0.15 mΩ
55.0 µF
I
Q
47 mA
+
–
K
+
–
1/8 • Vin
C
OUT
V
OUT
–
–
©
Figure 20—This
model characterizes the AC operation of the V•I Chip 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.
vicorpower.com
800-735-6200
V•I Chip Voltage Transformation Module
V048K060T040
Rev. 1.0
Page 11 of 15
VICOR [ VICOR CORPORATION ]
