Vicor VI-J00 Family DC-DC Converters and Configurable Power Supplies - Manual (Page 66)

Design Guide & Applications Manual
For VI-200 and VI-J00 Family DC-DC Converters and Configurable Power Supplies
VI-200 and VI-J00 Family Design Guide Rev 3.5 vicorpower.com
Page 65 of 98
Apps. Eng. 800 927.9474 800 735.6200
VI-200
Part #30089 Part #30775 Part #30090 Part #30780 Part #30193 Part #30194
FinMod FinMod
MI-200
Baseplate 0.9"L Fins [a] 0.7"L Fins 0.9"T Fins [b] 1.45"L Fins 0.7"T Fins 0.4"T Fins SlimMod
–F1 / –F3 –F2 / –F4
θbs = 0.2
(22,86 mm) (17,78 mm) (22,86 mm) (36,83 mm) (17,78 mm) (10,16 mm)
θsa θsa θsa θsa θsa θsa θsa θsa θsa θsa
Free Air 5.10 3.40 4.08 2.70 2.60 3.15 3.80 5.40 5.00 3.70
200 LFM 2.80 1.50 1.80 1.10 1.00 1.28 1.55 3.20 2.40 1.80
400 LFM 1.80 1.00 1.20 0.80 0.60 0.93 1.13 2.20 1.50 1.20
600 LFM 1.40 0.80 0.96 0.60 0.50 0.70 0.84 1.60 1.10 0.90
800 LFM 1.20 0.60 0.72 0.50 0.40 0.58 0.70 1.30 0.90 0.70
1,000 LFM 1.00 0.50 0.60 0.40 0.30 0.47 0.56 1.20 0.80 0.60
VI-J00
Part #30191 Part #30771 Part #30140
FinMod FinMod
MI-J00
Baseplate 0.9" L Fins 0.9" T Fins 0.4" T Fins SlimMod
–F1 / –F3 –F2 / –F4
θbs = 0.4
(22,86 mm) (22,86 mm) (10,16 mm)
θsa θsa θsa θsa θsa θsa θsa
Free Air (H) 8.10 4.20 4.00 5.63 8.50 8.00 7.00
Free Air (V) 7.60 4.00 3.90 5.49 8.40 7.30 6.70
200 LFM 5.10 1.60 1.60 2.25 5.50 5.00 2.70
400 LFM 2.70 1.30 1.30 1.83 3.60 2.50 1.50
600 LFM 2.30 0.90 0.90 1.27 2.90 2.10 1.20
800 LFM 1.70 0.70 0.70 0.99 2.30 1.30 0.80
1,000 LFM 1.40 0.60 0.60 0.84 2.00 1.10 0.70
Configurables
FlatPAC [c] ComPAC [c] MegaMod [c]
(also applies to MI-ComPAC
1-Up 2-Up 3-Up 1-Up 2-Up 3-Up 1-Up 2-Up 3-Up
and MI-MegaMod)
θbm θbm θbm θbm θbm θbm θbm θbm θbm
0.1 0.05 0.03 0.1 0.05 0.03 0.1 0.05 0.03
θsa θsa θsa θsa θsa θsa θsa θsa θsa
Free Air 2.1 1.3 1.0 3.6 1.7 1.4 4.4 2.1 1.7
50 LFM 1.5 1.1 0.9 2.7 1.4 1.3 3.3 1.7 1.6
100 LFM 1.2 0.9 0.7 2.3 1.3 1.1 2.8 1.6 1.3
250 LFM 0.7 0.5 0.4 1.6 1.0 0.8 2.0 1.2 1.0
500 LFM 0.4 0.3 0.3 1.2 0.7 0.6 1.5 0.9 0.7
750 LFM 0.3 0.2 0.2 0.9 0.5 0.5 1.1 0.6 0.6
1,000 LFM 0.2 0.2 0.2 0.8 0.4 0.4 1.0 0.5 0.5
[a] Longitudinal fins
[b] Transverse fins
[c] Assumes uniform loading of two and three output units.
Thermal Impedance Table (°C/W)
improvement in baseplate temperature results in
significant improvement in MTBF. If you are paying for
a fan, you may as well leverage it for all that it is worth.
3. Steps 5 through 7 in the Free Convection section will
complete the heat sink selection process. Select the fan
/ heat sink combination with the lowest thermal resistance
consistent with cost and space constraints, calculate the
estimated baseplate temperature and test to verify.
NOTE: The values of
θsa incorporating add-on or
integral heat sinks include the baseplate-to-heat sink
thermal resistance
θba. When using heat sinks from
other sources, the thermal impedance baseplate-to-air
will be the sum of the thermal impedance heat sink-
to-air specified by the heat sink manufacturer and the
baseplate-to-heat sink impedance from the following
Thermal Impedance Charts that follow.
20. Thermal and Module Mounting Considerations
Table 20–2a — Thermal impedance for VI-200 / MI-200
Table 20–2b — Thermal impedance for VI-J00/MI-J00
Table 20–2c — Thermal impedance for FlatPAC, ComPAC / MI-ComPAC and MegaMod /MI-MegaMod Families
TABLE USAGE: The forced convection thermal impedance data shown in the tables below assumes airflow
through the heat sink fins. Actual airflow through the fins should be verified. For purposes of heat sink
calculation, assume efficiencies of 81% for 5 V outputs and 85% for 12 V and above.