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

PI2126
Series
30 Volt, 12 Amp Full-Function Active ORing Solution
Description
Features
The PI2126 is a complete full-function
Active ORing solution with a high-speed ORing MOSFET
controller and a very low on-state resistance MOSFET
designed for use in 12V Bus redundant power system
architectures. The PI2126 Cool-ORing solution is offered
in an extremely small, thermally enhanced 5mm x 7mm
LGA package and can be used in high side Active ORing
applications. The PI2126 enables extremely low power
loss with fast dynamic response to fault conditions,
critical for high availability systems.






Integrated High Performance 12A, 4.5mΩ MOSFET
Very small, high density fully-optimized solution with
simple PCB layout
Fast dynamic response to power source failures,
with 90ns reverse current turn-off delay time
Accurate sensing capability to indicate system fault
conditions (-6mV reverse threshold)
Internal charge pump
Fault Status output
Applications
The PI2126, with its 4.5mΩ internal MOSFET provides
very high efficiency and low power loss during steady
state operation. The PI2126 monitors the current
direction in the MOSFET and will respond very fast to a
reverse current due to input power source fault
condition to prevent undesired high current build-up in
the system. The PI2126 provides an active low fault flag
output to the system during reverse current, excessive
forward over-current and UVLO fault conditions.


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N+1 Redundant Power Systems
Servers & High End Computing
Telecom Systems
High-side Active ORing
Package Information
The PI2126 is offered in the following package:

25-pin 5mm x 7mm thermally enhanced LGA
package, achieving <11°C/W RθJ-PCB
Typical Application:
Vin1
S
SP
VR
PI2126
SN
Applied Input Short
FT
PG
VC
D
FT
Normal operation
0A
Input
Current
S
SP
PG
VC
PI2126
V(D) Redundant Bus
FT
FT
V(S) (Input)
Reverse detection
MOSFET Turn Off Time
0V
Figure 1: PI2126 High Side Active ORing
Picor Corporation • picorpower.com
MOSFET
Miller Effect
VR
D
SN
LOAD
Vin2
Reverse Current
90ns
Figure 2: PI2126 response time to an input short fault
condition
PI2126
Rev 1.1
Page 1 of 15
Pin Description
Pin
Name
D
S
Pin Number
Description
1, 15, 16 17,
22, 23, 24, 25
Drain: The Drain of the internal N-channel MOSFET. Connect this pin to the output load.
2, 3, 4, 5, 18,
19, 20, 21
Source: The source of the internal N-channel MOSFET. Connect this pin to the input power
source bus voltage.
SP
6
Positive Sense Input & Clamp: Connect SP pin to the trace between S pin and the input source
(outside of the PI2126 foot print). The polarity of the voltage difference between SP and SN
provides an indication of current direction through the MOSFET.
VR
7
Controller Input Supply With Limiting Resistor: This pin is connected internally to VC through
a 420Ω resistor added for Bus voltages greater than 10V and less than 14V.
VC
8
Controller Input Supply: This pin is the supply pin for the control circuitry and gate driver.
Voltage on this pin is regulated to 11.7V with respect to PG pin by an internal shunt regulator.
NC
9, 12
Not Connected: Leave these pins unconnected.
PG
10, 11
Control Circuitry Return: These pins are ground return for the gate driver and control circuitry.
In 12V applications connect these pins to ground.
13
Fault Status Output: This open collector pin pulls low after a delay when a reverse fault or a
forward fault occurs. When the input voltage to the control circuitry is in under voltage, VVC-PG <
7V this pin pulls low. When VVC-PG > 7.15V and 6mV < SP-SN < 275mV this pin clears (High).
Leave this pin unconnected if unused.
14
Negative Sense Input: Connect SN pin to the trace between D pin and the output load (outside
of the PI2126 foot print). The polarity of the voltage difference between SP and SN provides an
indication of current direction through the MOSFET.
SN
Package Pin-Out
S
2
S 3
S 4
D
1
18
S
D
22
19
S
D
23
20
S
D
24
21
S
D
25
17 D
16 D
S 5
15 D
SP 6
PI2126
VR 7
8
VC
9
NC
10
PG
11
PG
14
SN
13
FT
12
NC
25-pin LGA (5mm x 7mm)
Top view
Picor Corporation • picorpower.com
PI2126
Rev 1.1
Page 2 of 15
Absolute Maximum Ratings
Note: All voltage nodes are referenced to PG
Drain-to-Source Voltage (VDS)
30V @ 25°C
Source Current (Is) Continuous
Source Current (Is) Pulsed (10μs)
12A
(1)
60A
Single Pulse Avalanche Current (TAV<40μs) (1)
60A
-0.3V to 17.3V / 10mA
Source (S), SP,
SN
-0.3V to 40V / 4mA
Thermal Resistance
RθJA(3)
46C/W
Thermal Resistance RθJ-PCB(3)
11C/W
Storage Temperature
-65°C to 150°C
Operating Junction Temperature
-40°C to 140°C
Soldering Temperature for 20 seconds
260°C
ESD Rating
2kV HBM
Electrical Specifications
Unless otherwise specified: -40C < TJ < 125C, VS =VC=10.5V,
Parameter
Symbol
Min
VVC-PG
8.5
Typ
Max
Units
Conditions
10.5
V
1.5
2.0
mA
11.7
12.5
V
IS=3mA
10

Delta IS=10mA
Control Circuit Supply (VC to PG)
Operating Supply Range
Quiescent Current
Clamp Voltage
Clamp Shunt Resistance
IVC
VVC-CLM
11
RVC
Under-Voltage Rising Threshold
VVCUVR
6.1
7.15
8.5
V
Under-Voltage Falling Threshold
VVCUVF
6
7.00
7.9
V
Under-Voltage Hysteresis
VVCUV-HS
100
150
200
mV
VR Supply (VR pin connected to Vin, Figure 1)
Operating Supply Range
VVR-PG
10
14
V
10
mA
550
Ω
Quiescent Current
Bias Resistor
Picor Corporation • picorpower.com
IVR
RBias
300
420
PI2126
No VC limiting Resistor
Normal operation, no fault
Biased From VR pin
VR = 14V
Rev 1.1
Page 3 of 15
Electrical Specifications
Unless otherwise specified: -40C < TJ < 125C, VS=VC=10.5V,
Parameter
Symbol
Max
Units
-3
3
V
VSP-SN
-80
400
mV
SP-SN
SP Input Bias Current
ISP
35
55
75
μA
VSP = VSN = VS
SN Input Bias Current
ISN
35
55
75
μA
VSP = VSN = VS
SN Current
Reverse Comparator Threshold
Reverse Comparator Hysteresis
MOSFET Turn On Threshold
Reverse Fault to MOSFETs Turn-off
Time
Forward Comparator Threshold
Forward Comparator Hysteresis
Internal N-Channel MOSFET
ISN
-11
10
+1
0.2
-6
12
+6
0.5
-2
14
+11
mA
mV
mV
mV
VSN = 14V, VSP = VS =VD=0V
VSN = 10.5V @ 25°C
VSP-PG = 10.5V @ 25°C
VSN = 10.5V @ 25°C
90
150
ns
VSP-SN = ± 50mV step
275
25
300
35
mV
mV
DIFFERENTIAL AMPLIFIER AND COMPARATORS
Common Mode Input Voltage
VCM
Differential Operating Input Voltage
(1)
VRVS-TH
VRVS-HY
VFET-ON
Min
tRVS
VFWD-TH
VFWD-HY
250
15
Drain-to-Source Breakdown Voltage
BVDSS
30
Source Current Continuous
Drain-to-Source On Resistance
Body Diode Forward Voltage
Fault:
Output Low Voltage
Output High Leakage Current
IS
RDS(on)
Vf-BD
Delay time
Typ
V
4.5
0.75
12
6
1.0
0.2
0.5
V
μA
8
16
μs
-1
4
A
m
V
Conditions
SP to S and SN to S
VS=VPG =VSP=0V, ID=2mA ,
Tj=25°C; VSN=10.5V
In ON state, Tj=25°C
In ON state, IS=10A, Tj=25°C,
In OFF state, IS=4A, Tj=25°C
IGST=1.5mA, VC>4.5V
VSP-SN = ± 50mV step to 90% of
max,
Note 1: These parameters are not production tested but are guaranteed by design, characterization, and correlation with
statistical process control.
Note 2: Current sourced by a pin is reported with a negative sign.
Note 3: Thermal resistance characterized on PI2126-EVAL1 evaluation board with 0LFM airflow.
Picor Corporation • picorpower.com
PI2126
Rev 1.1
Page 4 of 15
Functional Description:
The PI2126 integrated Cool-ORing product takes
advantage of two different technologies combining a
4.5m on-state resistance (RDS(on)) N-channel MOSFET
with high density control circuitry. This combination
provides superior density, minimizing PCB space to
achieve an ideal ORing diode function, significantly
reducing power dissipation and eliminating the need for
heat sinking, while minimizing design complexity.
Figure 3: Reverse comparator hysteresis, the hysteresis
voltage is SP-SN
Forward Voltage Comparator: FWD
The PI2126’s 4.5mΩ on-state resistance MOSFET used in
the conduction path enables a dramatic reduction in
power dissipation versus the performance of a diode
used in conventional ORing applications due to its high
forward voltage drop.
The FWD comparator detects when a forward voltage
condition exists and SP is above 275mV (typical) positive
with respect to SN. When SP-SN is more than 275mV, the
FWD comparator will assert the Fault ( ) low to report a
fault condition.
Due to the inherent characteristics of the MOSFET, while
the gate remains enhanced above the gate threshold
voltage it will allow current to flow in the forward and
reverse directions. Ideal ORing applications do not allow
for reverse current flow, so the controller has to be
capable of very fast and accurate detection of reverse
current caused by input power source failures, and turn
off the gate of the MOSFET as quickly as possible. Once
the gate voltage falls below the gate threshold, the
MOSFET is off and the body diode will be reverse biased
preventing reverse current flow and subsequent
excessive voltage droop on the redundant bus.
VC and Internal Voltage Regulator:
The PI2126 has a separate input VC that provides power
to the control circuitry. An internal regulator clamps the
VC voltage with respect to PG pin (VVC-PG) to 11.7V
typical.
The internal regulator circuit has a comparator to
monitor VC voltage and pulls the MOSFET Gate low when
VC is lower than the VC Under-Voltage Threshold.
The VR input pin can be connected to the input voltage
eliminating the need for an external limiter in 12V Bus
applications (10V to 14V). An internal 420Ω resistor is
connected between the VR pin and the internal regulator
VC pin.
Differential Amplifier:
The PI2126 integrates a high-speed low offset voltage
differential amplifier to sense the difference between the
Sense Positive (SP) pin voltage and Sense Negative (SN)
pin voltage with high accuracy. The amplifier output is
connected to the Reverse and Forward comparators.
Fault Indication:
The
pin is an open collector NPN that will be pulled
low under the following fault conditions.
Reverse Current Comparator: RVS
The reverse current comparator provides the critical
function in the controller, detecting negative voltage
caused by reverse current. When the SN pin is 6mV
higher than the SP pin, the reverse comparator will force
the gate discharge circuit to turn off the MOSFET in
typically 90ns and assert the Fault ( ) low with a typical
delay of 8μs to report a fault condition.
The reverse comparator will hold the gate low until the
SP pin is 6mV higher than the SN pin. Reverse
comparator hysteresis is shown in Figure 3.
Picor Corporation • picorpower.com
Typical Condition
Indication of possible faults
1
Reverse:
VSP-VSN ≤ -6mV
Input supply shorted
(MOSFET turned OFF)
2
Forward:
VSP-VSN ≥ +275mV
Open FET, Gate short or
open, High current
(MOSFET turned ON)
3
Forward
VSP-VSN ≤ +6mV
Shorted FET on power-up
(MOSFET turned OFF)
4
UVLO
4.5V <
PI2126
VVC-PG <7.15V
Rev 1.1
Controller not ready
(MOSFET turned OFF)
Page 5 of 15
S
5 4 3 2
VC
VC
VR
SP
8
18
+
7
7.15V
420Ω
+
SN
14
11.7V
20
2X
Charge
Pump
Differential
Amplifier
6
19
EN
-
+ RVS
-
+6mV
Hys= -12mV
0.1μF
+275mV
Hys= -25mV
21
GATE
RVS
-
Gate
Driver
+ FWD
FWD
-
S
22
FT
23
24
D
24
10
11
13
15 16 17 1
PG
PG
FT
D
Figure 4: PI2126 Internal Block Diagram
SP-SN < +6mV
7.
0V
VS-PG < 7.15V
VS-PG >7.15V
VS-PG>4.5V
MOSFET OFF
FT : Low
Turn Off MOSFET
& Pull FT Low
SPG
<
V
Reverse Cleared
SP-SN > +6mV
MOSFET OFF
FT : Low
SP-SN > -6mV
<7
G
-P
R
V
m
n
-6
tio
<
di
N
on
C
-S
se
SP
er
ev
VS
.0V
FT : High
FT : High
Turn MOSFET ON &
Hold it in RDS(on)
Fault
Recovery
FT : Low
Fault Condition
SP-SN >275mV: Open FET, Gate short or open, High Current
Figure 5: PI2126 State Diagram.
Picor Corporation • picorpower.com
PI2126
Rev 1.1
Page 6 of 15
Iin_1
Vin_1
S
ORing_1
D
V_Load
Vin_2
Iin_2 S
ORing_2
D
Load
OR1 VC
>7.15V
Vin
Vin_1
OR1VC
>4.5V
Vin_2 >Vin_1
Vin_2
Vin1
Shorted
Vin_2 Delayed
Iin
Vin2 >Vin1
Iin_1
Iin_2
FET turn on delay
Reverse Current
FET in Rds_ON
V_Load
FET body diode conducting
VSP-VSN≥275mV
FT_1
VSP-VSN<-6mV
-6mV<VSP-VSN<275mV
VSP-VSN<-6mV
VSP-VSN>+6mV
FT_2
VSP-VSN<+6mV
-6mV<VSP-VSN<275mV
Figure 6: PI2126 Timing Diagram
Picor Corporation • picorpower.com
PI2126
Rev 1.1
Page 7 of 15
Typical Characteristics:
1.2
ID=2mA
VVC-SGND=10.5V
1.1
1.50
Normaized: BVDSS
VC Quiescent Current [mA]
1.55
1.45
1.0
0.9
0.8
1.40
-50
-25
0
25
50
75
-50
100 125 150
-25
1.6
VVC-SGND=10.5V
75
100 125 150
IS=10A
1.5
-4.00
1.4
-5.00
Normaized: RDS(on)
Reverse Comparator Threshold [mV]
50
Figure 8: Drain-to-Source Breakdown Voltage (BVDSS ) vs.
temperature
-3.00
-6.00
-7.00
-8.00
1.3
1.2
1.1
1.0
0.9
0.8
0.7
-9.00
-50
-25
0
25
50
75
-50
100 125 150
Figure 9: Reverse Comparator Threshold (VRVS-TH) vs.
temperature
95
-25
0
25
50
75
100 125 150
Junction Temperature [°C]
Junction Temperature [°C]
Figure 10: Drain-to-Source On Resistance (RDS(on)) vs.
temperature.
100
VSP-SN =+50mV to -50mV step
IS=4A
94
93
IS: Source Current [A]
Reverse Fault to response Time [ns]
25
Junction Temperature [°C]
Junction Temperature [°C]
Figure 7: Controller quiescent current (IVC:) vs. temperature.
0
92
91
90
89
88
87
TJ=150°C
TJ=25°C
10
1
-50
-25
0
25
50
75
100 125 150
0.2
Picor Corporation • picorpower.com
0.6
0.8
1.0
1.2
Vf-BD: Body Diode Forward Voltage [V]
Junction Temperature [°C]
Figure 11: Reverse Fault to MOSFETs Turn-off Time (tRVS) vs.
temperature.
0.4
Figure 12: Body Diode Forward Voltage (Vf-BD) vs. temperature.
PI2126
Rev 1.1
Page 8 of 15
Thermal Characteristics:
150
150
Air Flow = 0LFM
Junction Temperature [°C]
Junction Temperature [°C]
RDS(on)=6.0mΩ @ 25°C
130
RθJA = 46°C/W
120
110
TA = 100°C
100
90
80
70
Air Flow = 200LFM
140
140
TA = 90°C
TA = 80°C
TA = 70°C
TA = 60°C
60
0
1
2
3
4
5
6
7
8
9
10 11
RθJA = 33°C/W
120
110
100
90
80
70
TA = 100°C
TA = 90°C
TA = 80°C
TA = 70°C
60 TA = 60°C
TA = 50°C
50
0 1 2
TA = 50°C
50
RDS(on)=6.0mΩ @ 25°C
130
12
3
4
Input Current [A]
5
6
7
8
9
10 11
12
Input Current [A]
Figure 13: Junction Temperature vs. Input Current (0LFM)
Figure 14: Junction Temperature vs. Input Current (200LFM)
13
200LFM, RDS(on)=4.5mΩ
Input Current [A]
12
0L
11
0L
F
FM
,R
DS
10
M
20
0L
F
,R
DS
(o n
) =6
M
,R
DS
(on
.0m
Ω
) =4
(o
n) =
.5m
Ω
6 .0
m
Ω
9
RθJA = 46°C/W at 0LFM
RθJA = 33°C/W at 200LFM
8
7
50
55
60
65
70
75
80
85
90
95
100
105
110
115
120
125
Ambient Temperature [°C ]
Figure 15: PI2126 input current de-rating based on maximum TJ=150°C vs. ambient temperature
MOSFET
PI2126
Figure 16: Thermal image of PI2126 mounted on PI2126-EVAL1Thermal Image picture, Iout=12A, TA=25°C, Air Flow=0LFM
Note that the MOSFET RDS(on) of PI2126 under test is 4.1mΩ at TA=25°C
Picor Corporation • picorpower.com
PI2126
Rev 1.1
Page 9 of 15
Application Information
The PI2126 is designed to replace high side ORing diodes in
high current low voltage bus redundant power
architectures. Replacing a traditional diode with a PI2126
will result in significant power dissipation reduction as well
as board space reduction, efficiency improvement and
additional protection features.
RPG selection for input voltage greater than 14V:
Select the resistor (RPG) value at the minimum input
voltage to avoid a voltage drop that may reduce VVC-PG
lower than VC under voltage lockout.
Select the value of RPG using the following equations:
This section describes in detail the procedure to follow
when designing with the PI2126 Active ORing solution.
And RPG maximum power dissipation is:
Control Circuitry Bias:
The PI2126 control circuitry and the gate driver for the
internal MOSFET are biased through the VC pin or VR pin.
An internal regulator clamps the VC voltage (VVC-PG) to
11.7V typically. An internal bypass ceramic capacitor
(0.1μF) is connected between VC and PG to hold VVC-PG
steady.
Where:
Vin1
S
SP
VR
PG
VC
D1
Maximum applied input voltage
: Controller maximum clamp voltage, 12.5V
:
Controller maximum bias current, use 2.0mA
:
0.1mA is added for margin
RPG calculation example
Vin (minimum) = 11V and Vin (maximum) = 18V
power dissipation.
SN
FT
:
Select a lower typical resistor value (1KΩ) and calculate its
D
PI2126
Minimum applied input voltage
: Controller maximum Under-Voltage Rising
Threshold, 8.5V
In 12V system applications, where the input voltage (Vin) is
between 10V and 14V, connect the VR pin to Vin and
connect PG to the Vin return, Figure 1. A 420Ω internal
resistor (RBias) is connected between the VR pin and the VC
pin.
In high voltage applications above 14V, PG pin has to float
above ground and VC pin will be connected directly to Vin.
As shown in Figure 17, VR pin is disconnected and PG pin
float on a bias resistor (RPG). A low current low forward
voltage drop Schottky diode is required for the PI2126
when PI2126 is configured floating on PG. Connect one
terminal of RPG to the PG pin and the other end of RPG to
ground (Vin return). Connect the Schottky diode anode to
the PG pin and connect its cathode to the VC pin.
:
FT
PMEG3005AEA
RPG
S
SP
VR
D
PI2126
PG
VC
D1
Internal N-Channel MOSFET BVDSS:
SN
FT
FT
PMEG3005AEA
RPG
Figure 17: PI2126 in application above 14V
Recommended Schottky Diode:
PMEG3005AEA: from NXP or equivalent
Picor Corporation • picorpower.com
LOAD
Vin2
The PI2126’s internal N-Channel MOSFET breakdown
voltage (BVDSS) is rated for 30V at 25°C and will degrade to
28V at -40°C, refer to Figure 8. Drain to source voltage
should not exceed BVDSS in nominal operation. During a
fast switching transient the MOSFET can tolerate voltages
higher than its BVDSS rating under avalanche conditions,
refer to the Absolute Maximum Ratings table.
In Active ORing applications when one of the input power
sources is shorted, a large reverse current is sourced from
PI2126
Rev 1.1
Page 10 of 15
the load through the MOSFET. Depending on the output
impedance of the system and the parasitic inductance, the
reverse current in the MOSFET may exceed the source
pulsed current rating (60A) before the PI2126 MOSFET is
turned off.
Where:
The peak current during an input short condition is
calculated as follows, assuming that the output has very
low impedance and it is not a limiting factor:
In Active ORing circuits the MOSFET is always on in steady
state operation and the power dissipation is derived from
the total source current and the on-state resistance of the
MOSFET.
:
:
:
The PI2126 internal MOSFET power dissipation can be
calculated with the following equation:
Peak current in PI2126 MOSFET before it is
turned off.
Where:
: MOSFET power dissipation
Input voltage or load voltage at S pin before
input short condition did occur.
:
MOSFET breakdown voltage (30V)
Power dissipation:
Where:
:
Avalanche energy
:
Source Current
Reverse fault to MOSFET turn-off time.
:
: Circuit parasitic inductance
Note: For the worst case condition, calculate with
maximum rated RDS(on) at the MOSFET maximum operating
junction temperature because RDS(on) value is directly
proportional to temperature. Refer to Figure 10 for
normalized RDS(on) values over temperature. The PI2126
maximum RDS(on) at 25°C is 6mΩ and will increase by 40% at
125°C junction temperature.
The high peak current during an input short stores energy
in the circuit parasitic inductance, and as soon as the
MOSFET turns off, the stored energy will be released and
this will produce a high negative voltage and ringing at the
MOSFET source. At the same time the energy stored at the
drain side of the internal MOSFET will be released and
produce a voltage higher than the load voltage. This event
will create a high voltage difference between the drain and
source of the MOSFET. The MOSFET may avalanche, but
this avalanche will not affect the MOSFET performance
because the PI2126 has a fast response time to the input
fault condition and the stored energy will be well below
the MOSFET avalanche capability.
The Junction Temperature rise is a function of power
dissipation and thermal resistance.
Where:
:
Junction-to-Ambient thermal resistance, 46°C/W
This may require iteration to get to the final junction
temperature. Figure 13 and Figure 14 show the PI2126
internal MOSFET final junction temperature curves versus
conducted current at maximum RDS(on), given ambient
temperatures and air flow.
MOSFET avalanche during input short is calculated as
follows:
Picor Corporation • picorpower.com
MOSFET on-state resistance
PI2126
Rev 1.1
Page 11 of 15
Typical application Example:
Requirement:
(Junction Temperature). The Junction Temperature at
maximum load current (10A) and 60°C ambient is 95°C.
Redundant Bus Voltage = 12V (±10%, 10.8V to 13.2V)
Load Current = 10A (assume through each redundant path)
150
Maximum Ambient Temperature = 60°C
140
Solution:
130
Junction Temperature [°C]
Air Flow = 0LFM
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
Vin1
2-5 & 18-21
6
S
D
SP
VR
8
VC
PI2126
PG
7
1,15-17 & 22-25
SN 14
FT
13
FT
10, 11
U2
S
SP
7
VR
8
VC
D
PI2126
PG
6
SN 14
FT
RθJA = 46°C/W
110
TA = 100°C
100
95 TA = 90°C
90
TA = 80°C
80
TA = 70°C
70
TA = 60°C
60
TA = 50°C
50
0 1 2
3
4
13
FT
5
6
7
8
9
10 11
12
Input Current [A]
1,15-17 & 22-25
Figure 19: Example 1 final junction temperature at 10A/60°C
LOAD
Vin2
2-5 & 18-21
120
RDS(on)=6.0mΩ @ 25°C
RDS(on) is 6mΩ maximum at 25°C and will increase as the
Junction temperature increases. From Figure 10, at 95°C
RDS(on) will increase by 26%, then
10, 11
Figure 18: PI2126 in 12V redundant bus voltage application
maximum at 95°C
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.
Maximum power dissipation is:
Recalculate TJ:
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
Picor Corporation • picorpower.com
PI2126
Rev 1.1
Page 12 of 15
Layout Recommendation:

Use the following general guidelines when designing
printed circuit boards. An example of the typical land
pattern for the PI2126 is shown in Figure 20:

Connect all S pads together with a wide trace to
reduce trace parasitics to accommodate the high
current input, and also connect all D pads together
with a wide trace to accommodate the high current
output.

Connect the SP pin to the S pins and connect the SN
pin to D pins outside the SiP as shown in Figure 20.

Use 1oz copper or thicker if possible to reduce trace
resistance and power dissipation.
PI2126
S
S S
S
S S
S
S
Vin
D
D D
D
D D
D
D
SP
VR
Vout
SN
PG
PG
Make sure to have a solid ground (return) plane to
reduce circuit parasitic inductance.
VC

C6 typically is not required, but if addition bypassing is
preferred, Figure 20 shows the appropriate layout for
an extra VC capacitor.
FT
CVC
Figure 20: Layout recommendation
Figure 21: PI2126 Mounted on PI2126-EVAL1
Please visit http://vicorpower.com/picorpower/ for information on PI2122-EVAL1
Picor Corporation • picorpower.com
PI2126
Rev 1.1
Page 13 of 15
Package Drawings:
Ordering Information:
Part Number
Package
Transport Media
PI2126-00-LGIZ
5mm x 7mm 25-pin LGA
TRAY
Picor Corporation • picorpower.com
PI2126
Rev 1.1
Page 14 of 15

Warranty
Vicor products are guaranteed for two years from date of shipment against defects in material or workmanship when in
normal use and service. This warranty does not extend to products subjected to misuse, accident, or improper application or
maintenance. Vicor shall not be liable for collateral or consequential damage. This warranty is extended to the original
purchaser only.
EXCEPT FOR THE FOREGOING EXPRESS WARRANTY, VICOR MAKES NO WARRANTY, EXPRESS OR LIMITED, INCLUDING, BUT
NOT LIMITED TO, THE WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
Vicor will repair or replace defective products in accordance with its own best judgment. For service under this warranty, the
buyer must contact Vicor to obtain a Return Material Authorization (RMA) number and shipping instructions. Products
returned without prior authorization will be returned to the buyer. The buyer will pay all charges incurred in returning the
product to the factory. Vicor will pay all reshipment charges if the product was defective within the terms of this warranty.
Information published by Vicor has been carefully checked and is believed to be accurate; however, no responsibility is
assumed for inaccuracies. Vicor reserves the right to make changes to any products without further notice to improve
reliability, function, or design. Vicor does not assume any liability arising out of the application or use of any product or
circuit; neither does it convey any license under its patent rights nor the rights of others. Vicor general policy does not
recommend the use of its components in life support applications wherein a failure or malfunction may directly threaten life
or injury. Per Vicor Terms and Conditions of Sale, the user of Vicor components in life support applications assumes all risks
of such use and indemnifies Vicor against all damages.
Vicor’s comprehensive line of power solutions includes high density AC-DC and DC-DC modules and
accessory components, fully configurable AC-DC and DC-DC power supplies, and complete custom
power systems.
Information furnished by Vicor is believed to be accurate and reliable. However, no responsibility is assumed by Vicor for its
use. Vicor components are not designed to be used in applications, such as life support systems, wherein a failure or
malfunction could result in injury or death. All sales are subject to Vicor’s Terms and Conditions of Sale, which are available
upon request.
Specifications are subject to change without notice.
Vicor Corporation
25 Frontage Road
Andover, MA 01810
USA
Picor Corporation
51 Industrial Drive
North Smithfield, RI 02896
USA
Customer Service: [email protected]
Technical Support: [email protected]
Tel: 800-735-6200
Fax: 978-475-6715
Picor Corporation • picorpower.com
PI2126
Rev 1.1
Page 15 of 15