iru3065 International Rectifier Corp., iru3065 Datasheet - Page 13
iru3065
Manufacturer Part Number
iru3065
Description
Positive To Negative Dc To Dc Controller
Manufacturer
International Rectifier Corp.
Datasheet
1.IRU3065.pdf
(15 pages)
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
Part Number:
iru3065CLTRPBF
Manufacturer:
IR
Quantity:
20 000
When I
age V
The above equation is used to select the current sens-
ing resistor R
Substitution of equation (16) into equation (13) results
in the relationship between frequency and output cur-
rent, that is
The above equation indicates that the switching fre-
quency decreases when output current increases dur-
ing power limit mode.
When I
maximum. Substitution of V
(6) into equation (13) results in the maximum switching
frequency:
Therefore, the inductance can be selected according
to the maximum desired frequency as shown in the fol-
lowing:
Fig. 24 and Fig.25 shows the theorectical predication
and calculation results for the output voltage and fre-
quency versus output current.
I
f
f
f
L
OCP
S
S(MAX)
S(MAX)
OUT
=
OUT
OUT
=
L I
=V
=I
=
=I
=
1
2
V
OUT(NOM)
OCP
IN
PEAK
OCP
S
V
.
V
, the output voltage equals nominal volt-
VI
OUT(NOM)
, the switching frequency reaches its
IN
V
R
V
V
IN
SEN
VI
S
IN
. From equation (15),we have
OUT(NOM)
(
(V
SEN
V
(V
(V
1 -
(V
D
OUT(NOM)
(V
) f
V
IN
D
- V
IN
IN
2 I
D
- V
+ V
(V
I
) L I
- V
+ V
S(MAX)
PEAK
- V
OUT(NOM)
IN
OUT
OUT(NOM)
V
OUT
D
) L
OUT(NOM)
OUT
+ V
D
IN
-
=V
)
-
+V
D
--(18)
PEAK
OUT(NOM)
) R
I
PEAK
-
)
D
)
S
and equation
---(17)
---(19)
---(20)
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Figure 24- The comparison between predicted and
Figure 25 - The comparison between predicted
measured output voltage versus output current
and measured switching frequency versus
6
5
4
3
2
1
0
1200
1000
Predicted fs(KHz)
800
600
400
200
0
Switching frequency versus output current
0
0
Predicted (-Vout)
Vout versus output current
0.2
output current
0.2
Output current (amp)
Output current (A)
IRU3065(PbF)
0.4
0.4
Experiment fs (kHz)
Measured -Vout
0.6
0.6
13
0.8
0.8