ip2005a International Rectifier Corp., ip2005a Datasheet - Page 9

• Manufacturer Part Number: ip2005a
• Description: High Frequency Synchronous Buck Optimized Lga Power Stage
• Manufacturer: International Rectifier Corp.

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Calculating Power Loss and SOA for Different Operating Conditions
To calculate Power Loss for a given set of operation conditions, the following procedure
should be followed:
Power Loss Procedure
1.Determine the maximum current for each iP2005A and obtain the maximum power loss
from Figure 1
2.Use the normalized curves to obtain power loss values that match the operating conditions
in the application
3.The maximum power loss under the application conditions is then the product of the power
loss from Figure 1 and the normalized values.
To calculate the Safe Operating Area (SOA) for a given set of operating conditions,
SOA Procedure
1.Determine the maximum PCB and CASE temperature at the maximum operating current
for each iP2005A
2.Use the normalized curves to obtain SOA temperature adjustments that match the
operating conditions in the application
3.Then, add the sum of the SOA temperature adjustments to the T
2
Design Example
Operating Conditions:
Output Current = 30A
Switching Freq = 750kHz Inductor = 0.2µH
Calculating Maximum Power Loss:
the following procedure should be followed:
(Figure 1)
(Figure 3)
(Figure 4)
(Figure 5)
(Figure 6)
Calculated Maximum Power Loss ≈ 9.0W x 0.95 x 1.0 x 1.026 x 0.87 ≈ 7.63W
Input Voltage = 10V
Maximum power loss = 9.0W
Normalized power loss for input voltage ≈ 0.95
Normalized power loss for output voltage ≈ 1.0
Normalized power loss for output inductor ≈ 1.026
Normalized power loss for switch frequency ≈ 0.87
2/8/2008
Output Voltage = 1.3V
Drive Voltage (V
X
iP2005APbF
axis intercept in Figure
DD
) = 5V
PD-60325
9