HIP6201 INTERSIL [Intersil Corporation], HIP6201 Datasheet - Page 8

• Manufacturer Part Number: HIP6201
• Manufacturer: INTERSIL [Intersil Corporation]

In actual systems, the load transient will most likely be of
varying frequency and step size. The power dissipation
of the HIP6200/1 becomes even more difficult to estimate
analytically.
HIP6200 Temperature Rise
The HIP6200/1 junction temperature can be estimated
simply by:
where:
T
JA
HIP6200
FIGURE 5. ESTIMATED HIP6200, HIP6201 POWER
0.6
0.5
0.4
0.3
0.2
0.1
is the thermal resistance from junction to ambient.
=
T
AMBIENT
DISSIPATION vs CONVERTER RESPONSE TIME
T
T
T
T
R1
R1
TRANSIENT FREQUENCY (Hz)
R1
R1
= 15 s, T
= 10 s, T
10
+
= 5 s, T
= 2 s, T
2
P
2-448
DISS
R2
R2
R2
R2
= 40 s
= 30 s
= 20 s
= 10 s
JA
10
3
HIP6200, HIP6201
(EQ. 8)
10
4
Example: HIP6200/1 Junction Temperature Calculation
T
P
T
In a similar fashion, one could estimate the maximum
allowable power dissipation for given maximum ambient and
transient loading and determine the boundary of maximum
transient frequency.
Example
Maximum Transient Frequency Calculation
T
T
the amount of pc board trace connected to HIP6200
Max P
From Figures 4 and 5, the estimated maximum transient
frequency is obtained for any of the seven cases shown. For
instance, from Figure 4, the maximum transient frequency is
about 4kHz for the 8A transient step and the conditions
stipulated.
AMBIENT
AMBIENT
HIP6200
HIP6200
DISS
JA
JA
= 100
= 80
DISS
= 0.2W
o
= 70
= 110
C/W (this number is dependent upon airflow and
o
= 70
= 70
C/W
= (110
o
o
o
C + (0.2 x 100) = 90
o
C
C
C max
o
C - 70
o
C)/(80
o
C/W) = 0.5W
o
C