PI2126 Datasheet, PDF (12/15 Pages) Vicor Corporation – 30 Volt, 12 Amp Full-Function Active ORing Solution

EOL
Typical application Example:
Requirement:
Redundant Bus Voltage = 12V (±10%, 10.8V to 13.2V)
Load Current = 10A (assume through each redundant path)
Maximum Ambient Temperature = 60°C
Solution:
A single PI2126 for each redundant 12V power source
should be used, configured as shown in the circuit
schematic in Figure 18. PG pin is connected to ground and
VR pin is connected to Vin,
U1
2-5 & 18-21
Vin1
S
6 _SP
7 _VR
8 _VC
PI2126
10, 11
1,15-17 & 22-25
D
SN ¹⁴
FT ¹³ FT
Vin2
U2
2-5 & 18-21
S
6 _SP
7 _VR
8 _VC
PI2126
10, 11
1,15-17 & 22-25
D
SN ¹⁴
FT ¹³ FT
Figure 18: PI2126 in 12V redundant bus voltage application
The fault pin ( ) can be pulled to the system logic level
voltage via a resistor (10kΩ), or it can be connected to the
input voltage (Vin) via a 25kΩ resistor.
Power Dissipation and Junction Temperature:
First use Figure 13 (Junction Temperature vs. Input
Current) to find the final junction temperature for 10A load
current at 60°C ambient temperature. In Figure 13
(illustrated in Figure 19) draw a vertical line from 10A to
intersect the 60°C ambient temperature line. At the
intersection draw a horizontal line towards the Y-axis
(Junction Temperature). The Junction Temperature at
maximum load current (10A) and 60°C ambient is 95°C.
150
Air Flow = 0LFM
140
R_DS(on)=6.0mΩ @ 25°C
130
RθJA = 46°C/W
120
110
TA = 100°C
100
95
90
TA = 90°C
TA = 80°C
80
TA = 70°C
70
60 ^{TA = 60°C}
TA = 50°C
50
0 1 2 3 4 5 6 7 8 9 10 11 12
Input Current [A]
Figure 19: Example 1 final junction temperature at 10A/60°C
R_DS(on) is 6mΩ maximum at 25°C and will increase as the
Junction temperature increases. From Figure 10, at 95°C
R_DS(on) will increase by 26%, then
maximum at 95°C
Maximum power dissipation is:
Recalculate T_J:
Picor Corporation • picorpower.com
PI2126
Rev 1.1
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