PI2121-EVAL1

®
PI2121-EVAL1
Cool-ORing ™ Series
PI2121-EVAL1 Full-Function Active ORing
Evaluation Board User Guide
Contents
Cool-ORing™ Series
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Page 1
PI2121 Product Description . . . . . . . . . . . . . . . . . . Page 2
Evaluation Board Terminal Description . . . . . . . . Page 2
Evaluation Board Schematic . . . . . . . . . . . . . . . . . Page 3
Bill of Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . Page 3
Evaluation Board Configuration . . . . . . . . . . . . . . Page 4
Test Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . Page 4
Thermal Images . . . . . . . . . . . . . . . . . . . . . . . . . . . Page 9
PCB Layouts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Page 10
Evaluation Board Mechanical Drawing . . . . . . . Page 11
The PI2121-EVAL1 Evaluation Board is intended to acquaint the
user with the benefits and features of the Cool-ORingTM PI2121
full function Active ORing solution. It is not designed to be
installed in end-use equipment.
Please read this document before setting up the PI2121-EVAL1
Evaluation Board and refer to the PI2121 product data sheet
for device specifications, functional description and
characteristics.
PI2121-EVAL1 Evaluation Board
featuring the Cool-ORing PI2121
Full-Function Active ORing Solution.
During operation, the power devices and surrounding
structures can be operated safely at high temperatures.
• Remove power and use caution when connecting and
disconnecting test probes and interface lines to avoid
inadvertent short circuits and contact with hot surfaces.
• When testing electronic products always use approved
safety glasses. Follow good laboratory practice and
procedures.
Introduction
The PI2121-EVAL1 allows the user to test the basic principle
and operational characteristics of an Active ORing function in
a redundant power architecture, while also experiencing the
benefits and value of the PI2121 solution versus conventional
Active ORing solutions. The PI2121-EVAL1 evaluation board is
configured to receive two independent power source inputs,
per a typical redundant power architecture, through two
Active ORing channels that are combined to form a
redundant power output. Each channel is capable of up to 24
A, and is suitable for redundant bus voltages up to 5 V. For
high current Active ORing, above 24 A, the two channels
provided on the evaluation board can be paralleled in a
master/slave configuration and OR'd with a second evaluation
board.
Picor Corporation • www.picorpower.com
The PI2121-EVAL1 evaluation board is designed with
optimized PCB layout and component placement to represent
a realistic high density final design for an embedded Active
ORing solution for ≤ 5V bus applications requiring up to 24 A.
This evaluation board is intended as an easy and simple way
to test the electrical and thermal performance of the PI2121
Full-Function Active ORing solution.
Both dynamic and steady state testing of the PI2121 can be
completed on the PI2121-EVAL1 evaluation board, in addition
to using the key features of the product. Dynamic testing can
be completed under a variety of system level fault conditions
to check for response time to faults.
This document provides basic instructions for initial start-up
and configuration of the evaluation board. Further
information on the functionality of the PI2121 can be found
in the PI2121 product data sheet.
PI2121-EVAL1 User Guide Rev 1.1 Page 1 of 12
Cool-ORingTM PI2121 Product Description
The Cool-ORing PI2121 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 redundant power system architectures. The PI2121 CoolORing solution is offered in an extremely small, thermally
enhanced 5 mm x 7 mm LGA package and can be used in low
voltage (≤ 5 Vbus) high side Active ORing applications. The
PI2121 enables extremely low power loss with fast dynamic
response to fault conditions, critical for high availability
systems. A master / slave feature allows the paralleling of
PI2121 solutions for high current Active ORing requirements.
The PI2121, with its 1.5 mΩ internal MOSFET provides very
high efficiency and low power loss during steady state
operation, while achieving high-speed turn-off of the internal
MOSFET during input power source fault conditions that
cause reverse current flow. The PI2121 provides an active low
fault flag output to the system during excessive forward
current, light load, reverse current, over-voltage,
under-voltage, and over-temperature fault conditions.
A temperature sensing function indicates a fault if the
maximum junction temperature exceeds 160°C. The
under-voltage and over-voltage thresholds are programmable
via an external resistor divider.
Figure 1 shows a photo of the PI2121-EVAL1 evaluation
board, with two PI2121 used to form the two Active ORing
channels. The board is built with two identical Active ORing
circuits with options and features that enable the user to fully
explore the capabilities of the PI2121 Cool-ORing solution.
Terminals Rating
Vin1, Vin2
Vaux1, Vaux2, (R7 = R14 = 10 Ω)
see Vaux section
8V / 24 A
-0.3 to 17.3 V / 40 mA
SL
-0.3 to 8.0 V / 10 mA
FT
-0.3 to 17.3 V / 10 mA
Figure 1 – PI2121-EVAL1 Evaluation Board (1.8" x 1.8")
Terminal
Vin1
Vaux1
Rtn1
Gnd
SL1
SL2
Vin2
Vaux2
Rtn2
FT1
FT2
Vout
Description
Power Source Input #1 or bus input designed to accommodate up to 24 A continuous current.
Auxiliary Input Voltage #1 to supply PI2121 (SiP1) VC power. Vaux1 should be equal to Vin1 plus
5 V or higher. See details in Auxiliary Power Supply (Vaux) section of the PI2121 data sheet.
Vaux1 Return Connection: Connected to Ground plane
Vin & Vout Return Connection: Three Gnd connections are available and are connected to a common
point, the Ground plane. Input supplies Vin1 & Vin2 and the output load at Vout should all be
connected to their respective local Gnd connection.
PI2121 (SiP1) Slave Input-Output Pin: For monitoring SiP1 slave pin. When SiP1 is configured as the
Master, this pin functions as an output that drives slaved PI2121 devices. When SiP1 is configured in
Slave mode, SL1 serves as an input.
PI2121 (SiP2) Slave Input-Output Pin: For monitoring SiP2 slave pin. When SiP2 is configured as the
Master, this pin functions as an output that drives slaved PI2121 devices. When SiP2 is configured in
Slave mode, SL2 serves as an input.
Power Source Input #2 or bus input designed to accommodate up to 24 A continuous current.
Auxiliary Input Voltage #2 to supply PI2121 (SiP2) VC power. Vaux2 should be equal to Vin2 plus 5 V or higher.
See details in Auxiliary Power Supply (Vaux) section of the PI2121 data sheet.
Vaux2 Return Connection: Connected to Ground plane
PI2121 (SiP1) Fault Pin: Monitors SiP1 fault conditions
PI2121 (SiP2) Fault Pin: Monitors SiP2 fault conditions
Output: SiP1 and SiP2 D pins connection, connect to the load high side.
Table 1 – PI2121-EVAL1 Evaluation Board terminals description
Jumper
J1, J3
J2
Description
BK Jumpers: Connect jumper across M for master mode and across S for slave mode. Remove jumper to adjust reverse
fault blanking time using Rbk. Rbk is R6 for SiP1 and R13 for SiP2 shown in the schematic, Figure 2.
Slave Jumper: Remove the jumper unless one of the PI2121 is configured in slave mode.
Table 2 – PI2121-EVAL1 Evaluation Board jumpers description
Picor Corporation • www.picorpower.com
PI2121-EVAL1 User Guide Rev 1.1 Page 2 of 12
SIP1
PI2121
Vin1
FT
UV
R3
BK
Vaux1
Rtn1
R4
2.00 K 1%
VC1
2.00 K 1%
R5
4.99 K
Vaux1
J2
SL2
13
GND3
GND4
UV2
OV1
SL1
VC1
C1
1 uF
D1
LTST-C191KRKT
SL1
14
C3
22 uF
BK1
J1
R6
NP
SL1
C6
NP
OV
7
8
Vaux1
FT1
OV1
SN
GND
UV1
SP
Vout2
12
6
VC
GND
Vout1
Vout
FT1
11
C4
NP
13.3 K 1%
1
17
16
15
D
D
D
D
SL
R2
8.45 K 1%
S
S
S
S
10
R1
GND
2
3
4
5
9
Vin1
R7
10 Ω
SL2
SIP2
PI2121
Vin2
FT
UV
R11
2.00 K 1%
R10
2.00 k 1%
Rtn2
VC2
R12
4.99 K
J3
UV2
OV
13
BK2
SL2
OV2
R13
NP
VC2
C2
1 µF
D2
LTST-C191KRKT
Vaux2
14
12
BK
Vaux2
GND
7
SN
11
OV2
SP
VC
FT2
8
Vaux2
UV2
C7
NP
FT2
6
GND
1
17
16
15
D
D
D
D
10
GND
C5
NP
S
S
S
S
SL
R9
13.3 K 1%
R8
8.45 K 1%
Q1
2
3
4
5
9
Vin2
NP: Not Populated
C4, C5, C6, C7, R6 and R13
R7
10 Ω
Figure 2 – PI2121-EVAL1 Evaluation Board schematic.
Item
QTY
Reference Designator
Value
1
2
C1, C2
1 µF
2
1
C3
22 µF
3
4
4
2
5
8
6
7
7
8
9
10
11
12
13
14
2
1
2
2
4
2
2
2
C4, C5, C6, C7
D1, D2
FT1, FT2, Rtn1, Rtn2,
SL1, SL2, Vaux1, Vaux2
Gnd1, Gnd2, Gnd3, Gnd4,
Vin1, Vin2, Vout1, Vout2
J1, J3
J2
R1, R8
R2, R9
R3, R4, R10, R11
R5, R12
R6, R13
R7, R14
15
2
SiP1, SiP2
Description
Capacitor, MLCC X5R,
1 µF,16 V
Capacitor, MLCC X7R,
22 µF, 25 V
Footprint
0603
1210
Not installed
8.45 KΩ
13.3 KΩ
2.00 KΩ
4.99 KΩ
Not Installed
10
PI2121
Manufacturer
LED, Super Red
1206
THIN 0603
Turret Test point
TURRET-1528
Turret Test point
TURRET-1502
Header Pins 0.1" pitch
Header Pins 0.1" pitch
Resistor, 8.45 KΩ, 1%
Resistor,13.3 KΩ,1%
Resistor, 2.00 KΩ,1%
Resistor, 4.99 KΩ,1%
2 x 3mm
2 x 2mm
0603
0603
0603
0603
0603
0603
Resistor, 10, 5%
Picor Full-Function 24 A
Cool-ORing Solution
5x7mm;17 pins
Lite-On, Inc.,
Keystone
Electronics
Keystone
Electronics
PICOR
Table 3 – PI2121-EVAL1 Evaluation Board bill of materials
Picor Corporation • www.picorpower.com
PI2121-EVAL1 User Guide Rev 1.1 Page 3 of 12
Reference Designator
C1, C2
C3
C4, C5, C6, C7
D1, D2
J1, J3
J2
R1, R8
R2, R9
R3, R10
R4, R11
R5, R12
R6, R13
R7, R14
SiP1, SiP2
Value
1µF
22µF
Not installed
LED
Jumper
Jumper
8.45KΩ
13.3KΩ
2.00KΩ
2.00KΩ
4.99KΩ
Not Installed
10Ω
PI2121
Functional Description
VC Bypass Capacitor
Output (Load) Capacitor
Snubber to reduce voltage ringing when the device turns off
To indicate a fault exist when it is on
To select between Master and Slave Modes
Connection between SL1 and SL2
UV Voltage Divider Resistor ( R2UV in Figure 4)
OV Voltage Divider Resistor ( R2OV in Figure 4)
UV Voltage Divider Resistor ( R1UV in Figure 4)
OV Coltage Divider Resistor ( R1OV in Figure 4)
LED Current Limiter
BK Delay Timer Programmable Resistor
VC Bias Resistor
Cool ORing SiP.
Table 4 – Component functional description
Initial Test Set Up
To test the PI2121-EVAL1 evaluation board it is necessary to
configure the jumpers (J1, J2 and J3) first based on the
required board configuration.
Failure to configure the jumpers prior to the testing may
result in improper circuit behavior.
Baseline Test Procedure (Refer to Figure 3)
1.0 Recommended Equipment
1.1
1.2
1.3
1.4
1.5
1.6
1.7
1.8
Two DC power supplies - 0-10 V; 25 A.
DC power supply 12 V; 100 mA.
DC electronic load - 50 A minimum.
Digital Multimeter
Oscilloscope.
Appropriately sized interconnect cables.
Safety glasses.
PI2121 Product Data sheet.
Figure 3 – Layout configuration for a typical redundant power application, using PI2121 with both solutions
configured in Master Mode.
Picor Corporation • www.picorpower.com
PI2121-EVAL1 User Guide Rev 1.1 Page 4 of 12
Before initial power-up follow these steps to configure the
evaluation board for specific end application requirements:
2.0 Undervoltage (UV) and Overvoltage (OV) resistors set up:
Vin
2.1 UV and OV programmable resistors are configured
for a 3.3 V Vin (BUS voltage) application in a tworesistor voltage divider configuration as shown in
Figure 4. UV is set to 2.6 V and OV is set for 3.8 V,
R1OV and R1UV are 2.00 KΩ 1%. If PI2121-EVAL1 is
required to be used in a different Vin voltage
application please follow the following steps to
change the resistor values.
UV
R1UV
PI2121
R2OV
OV
R1OV
2.1.1 It is important to consider the maximum
current that will flow in the resistor divider
and maximum error due to UV and OV input
current.
R1UV =
V_Logic
R2UV
IRUV
2.1.2 Set R1UV and R1OV value based on system
allowable minimum current and 1% error;
IRUV ≥ 100 µA
FT
GND
Ref. Desg.
V(UVTH)
FT
SiP1
SiP2
R1UV
R3
R10
R2UV
R1
R8
R1OV
R4
R11
R2OV
R2
R9
Figure 4 – UV & OV two-resistor divider configuration
R2UV = R1UV
(
V(UV)
–1
V(UVTH)
)
Where:
V(UVTH) : UV threshold voltage
V(UV) : UV voltage set (0.5 V typ)
IRUV: R1UV current
R2OV = R1OV
(
V(OV)
–1
V(OVTH)
)
Where:
V(OVTH) : OV threshold voltage
V(OV) : OV voltage set (0.5 V typ)
IROV: R1OV current
2.1.3 Example for 2.0 V Vin (BUS voltage), to set UV and OV for ±10% Vin set UV at 1.8 V and OV at 2.2 V.
R2UV= R1UV
(
)
(
1.8 V
0.5 V
–1 = 5.20 KΩ (or 5.23 KΩ % standard value)
R2OV= R1OV
( V(OV ) )
(
2.2 V
–1 = 6.80 KΩ (or 6.81 KΩ % standard value)
V(UV)
–1 = 2.00 KΩ*
V(UVTH)
V(OV)
TH
–1 = 2.00 KΩ*
Picor Corporation • www.picorpower.com
0.5 V
)
)
PI2121-EVAL1 User Guide Rev 1.1 Page 5 of 12
3.0 Blanking timer setup:
3.1 The blanking timer provides noise filtering for
typical switching power conversion that might
cause premature reverse current detection by
masking the reverse fault condition. The shortest
blanking time is 50 ns when the BK pin is
connected to ground. Connecting an external
resistor (RBK, reference designators R6 for SiP1 and
R13 for SiP2) between the BK pin and ground will
increase the blanking time as shown in Figure 5.
Where: RBK ≤ 200 KΩ
Note: When BK is connected to VC for slave mode .
operation,then the blanking time will be 270 ns typically.
4.4.1 Select the value of Rbias using the following
equation:
Rbias =
4.4.2
Vauxmin – VCclampMAX
ICmax
Calculate Rbias maximum power dissipation:
PdRbias =
(Vauxmax – VCclampMIN)2
Rbias
Where:
Vauxmin: Vaux minimum voltage
Vauxmax: Vaux maximum voltage
VCClampMAX: Maximum controller
clamp voltage, 16.0 V
VCClampMIN: Minimum controller
clamp voltage, 14.0 V
ICmax: Controller maximum bias current,
use 4.2 mA
4.4.3 For example, if the minimum Vaux = 22 V
and the maximum Vaux = 28 V
Rbias =
Vauxmin – VCclampMAX
ICmax
=
22 V–16 V
= 1.429 KΩ
4.2 mA
,use 1.43 KΩ 1% resistor
PdRbias = (Vauxmax – VCclampMIN)2 = (28 V–14.0 V)2 =137 mW
Rbias
1.43 KΩ
Figure 5 –BK Resistor selection versus Blanking Time
4.0 Auxiliary Power Supply (Vaux):
4.1 The PI2121 ORing solution has a separate input (VC)
that provides power to the control circuitry and
the internal gate driver. An internal voltage regulator
(VC) clamps the VC voltage to 15.5 V typically.
Note: Minimize the resistor value for low Vaux voltage
levels to avoid a voltage drop that may reduce the VC
voltage lower than required to drive the gate of the
internal MOSFET.
4.2 Connect an independent power source to the Vaux
inputs of PI2121-EVAL1 Evaluation Board to supply
power to the VC inputs. The Vaux voltage should be
5 V higher than Vin (redundant power source output
voltage) to fully enhance the internal MOSFET.
4.3 10 Ω bias resistors (Rbias, reference designators R7
and R14) are installed on the PI2121-EVAL1 board
between each Vaux input and VC pin of the
PI2121 solution.
4.4 If Vaux is higher than the Clamp voltage, 15.5 V
typical, the Rbias value has to be changed using
the following equations:
Picor Corporation • www.picorpower.com
PI2121-EVAL1 User Guide Rev 1.1 Page 6 of 12
5.0 Hook Up of the Evaluation Board
5.21 Enable (turn ON) PS2 output then Enable PS3 output.
5.1 OV and UV resistors values are configured for a 3.3 V
input voltage. If you are using the evaluation
board in a different input voltage level you have to
adjust the resistor values by replacing R1, R2, R8
and R9, or remove R2, R3, R9 and R10 to disable UV
and OV. Please refer to the UV/OV section for
details to set R1, R2, R8 and R9 proper values.
5.22 Verify that the electronic load voltage reading is
few millivolts below 3.3 V. This verifies that the PI2121
(SiP2) internal MOSFET is in conduction mode.
5.2 Verify that the jumpers J1 and J3 are installed for
master mode [across M] and no Jumper on J2.
5.25 D2 should turn on, this verifies that the circuit is in
an under-voltage fault condition.
5.3 Connect the positive terminal of PS1 power supply
to Vin1. Connect the ground terminal of PS1 to its
local Gnd. Set the power supply to 3.3 V.
Keep PS1 output disabled (OFF).
5.26 Increase PS2 output to 3.3 V, D2 should turn off,
then increase PS2 output to 4 V, D2 should turn on
indicating an over voltage fault condition.
5.4 Connect the positive terminal of PS2 power supply
to Vin2. Connect the ground terminal of PS2 to its
local Gnd. Set the power supply to 3.3 V. Keep PS2
output disabled (OFF).
5.5 Connect the positive terminal of PS3 power supply
to Vaux1 and Vaux2. Connect the ground terminal
of this power supply to Rtn1 and Rtn2. Set the
power supply to 12 V. Keep PS3 output disabled (OFF).
5.6 Connect the electronic load to the output between
Vout and Gnd. Set the load current to 10 A.
5.7 Enable (turn ON) PS1 power supply output.
5.8 Turn on the electronic load.
5.9 Verify that the electronic load input voltage
reading is one diode voltage drop below 3.3 V.
5.10 Enable (turn ON) PS3 power supply output.
5.23 D2 should be off. This verifies that there is no
fault condition.
5.24 Reduce PS2 output voltage to 2 V,
5.27 Verify that Vin1 is at 0V. This verifies that the
PI2121 (SiP1) internal FET is off.
5.28 D1 should be on. This is due to a reverse voltage
fault condition caused by the bus voltage being
high with respect to the input voltage (Vin1).
6.0 Slave Mode: Slave Mode can be demonstrated in two
setups; either by using one PI2121-EVAL1 evaluation board
as a single ORing function with both PI2121 effectively in
parallel or two PI2121-EVAL1 evaluation boards to
demonstrate a true redundant 48 A system. The following
test steps uses a single PI2121-EVAL1 in a slave mode
application.
Note: In this experiment SiP 1 is configured in master mode and
SiP2 is configured in slave mode.
5.11 Verify that the electronic load voltage reading
increases to a few millivolts below 3.3 V. This
verifies that the PI2121 (SiP1) internal MOSFET is in
conduction mode.
6.1 BK pin (J1) of the master device will be connected
to ground [across M] while the slaved device BK pin
(J3) is connected to VCC [across S]. Place a jumper
across J2 to connect slave pins together.
5.12 D1 should be off. This verifies that there is no
fault condition.
6.2 Connect the positive terminal of PS1 power supply
to Vin1. Connect the ground terminal of this power
supply to Gnd. Set the power supply to 3.3 V. Keep
PS1 output disabled (OFF).
5.13 Reduce PS1 output voltage to 2 V,
5.14 D1 should turn on, this verifies that the circuit is in
an under-voltage fault condition.
5.15 Increase PS1 output to 3.3 V, D1 should turn off,
then increase PS1 output to 4 V, D1 should turn on
indicating an over-voltage fault condition
5.16 Verify that Vin2 is at 0V. This verifies that the
PI2121 (SiP2) internal FET is off.
5.17 D2 should be on. This is due to a reverse voltage
fault condition caused by the bus voltage being
high with respect to the input voltage (Vin2).
5.18 Enable (turn ON) PS2 output.
6.3 Connect the positive terminal of PS2 power supply
to Vin2. Connect the ground terminal of this power
supply to Gnd. Set the power supply to 3.3 V. Keep
PS2 output disabled (OFF).
6.4 Connect the positive terminal of PS3 power supply
to Vaux1 and Vaux2. Connect the ground terminal
of this power supply to Rtn1 and Rtn2. Set the
power supply to 12 V. Keep PS3 output disabled (OFF).
6.5 Connect the electronic load between Vout and
Gnd. Set the load current to 10 A.
5.19 Verify that both PS1 and PS2 are sharing load
current evenly by looking at the supply current.
6.6 Enable (Turn ON) PS2, and PS3 outputs, and keep
PS1 output disabled (OFF).
5.20 Disable (turn OFF) PS1, PS2 and PS3 outputs.
6.7 Turn on the electronic load.
Picor Corporation • www.picorpower.com
PI2121-EVAL1 User Guide Rev 1.1 Page 7 of 12
6.8 Verify that electronic load voltage drops to a diode
drop below PS2. This verifies that the SiP2 internal
FET is off due to the Master (SiP1) not being on.
6.9 Enable (turn on) PS1 output:
6.10 Verify that the electronic load input voltage
reading is a few millivolts below 3.3 V and PS1 and
PS2 are sharing the load current evenly. This
verifies that both internal MOSFET's of SiP1 and
SiP2 are in conduction mode.
7.0 Input short circuit test
7.1 To emulate a real application, the BUS supplies for
this test should have a solid output source such as
DC-DC converter that supplies high current and can
be connected very close to the evaluation board to
reduce stray parasitic inductance. Or use the
prospective supply sources of the end application
where the PI2121 will be used.
7.2 Stray parasitic inductance in the circuit can
contribute to significant voltage transient
conditions, particularly when the internal MOSFET
is turned-off after a reverse current fault has been
detected. When a short is applied at the output of
the input power sources and the evaluation board
input (Vin), a large reverse current is sourced from the
evaluation board output through the ORing
internal MOSFET. The reverse current in the
MOSFET may reach over 60 A in some conditions
before the MOSFET is turned off. Such high
current conditions will store high energy even in a
small parasitic element, and can be represented as
1 2
2 Li . A 1 nH parasitic inductance with 60 A reverse
current will generate 1.8 µJ. When the MOSFET is
turned off, the stored energy will be released and
will produce a high negative voltage at the MOSFET
source and high positive voltage at the MOSFET
drain. This event will create a high voltage
difference across the drain and source of the
MOSFET.
7.3 Apply a short at one of the inputs (Vin1 or Vin2)
when the evaluation board is configured with both
SiP's (SiP1 and SiP2) in master mode. The short can
be applied electronically using a MOSFET
connected between Vin and Gnd or simply by
connecting Vin to Gnd. Then measure the
response time between when the short is applied
and the SiP internal MOSFET is disconnected (or
turned off). An example for PI2121 response time
to an input short circuit is shown in Figure 6.
Figure 6 – Plot of PI2121 response time to reverse current detection
Picor Corporation • www.picorpower.com
PI2121-EVAL1 User Guide Rev 1.1 Page 8 of 12
8.0 Internal MOSFET Rds(on) Measurement:
Thermal Images
8.1 The SiP1 internal MOSFET Rds(on) can be measured
with a voltmeter between the S1 and D1 Kelvin
connection. The potential between S1 and D1 is
the voltage drop across the internal MOSFET and:
Rds(on) = VS1–VD1
Iin
Where:
VS1–VD1: Voltage drop across the internal MOSFET
Iin: Input current.
Note: The Rds(on) value is temperature dependent and the
junction temperature increases directly proportional to
power dissipation.
Figure 7a – PI2121 mounted on PI2121-EVAL1, Iout=24 A,
TA=25°C, Air Flow=0 LFM
Figure 7b – PI2121 mounted on PI2121-EVAL1 Iout=24 A,
TA=25°C, Air Flow=200 LFM
Picor Corporation • www.picorpower.com
PI2121-EVAL1 User Guide Rev 1.1 Page 9 of 12
Figure 8a – PI2121-EVAL1 layout top layer. Scale 2.0:1
Figure 8c – PI2121-EVAL1 layout mid layer 1. Scale 2.0:1
Picor Corporation • www.picorpower.com
Figure 8b – PI2121-EVAL1 layout mid layer 2. Scale 2.0:1
Figure 8d – PI2121-EVAL1 layout Bottom layer. Scale 2.0:1
PI2121-EVAL1 User Guide Rev 1.1 Page 10 of 12
Mechancial Drawing
Picor Corporation • www.picorpower.com
PI2121-EVAL1 User Guide Rev 1.1 Page 11 of 12
Vicor’s comprehensive line of power solutions includes high-density AC-DC & DC-DC
modules and accessory components, fully configurable AC-DC & 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. No license is granted by implication or otherwise under any patent
or patent rights of Vicor. 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 • www.picorpower.com
PI2121-EVAL1 User Guide Rev 1.1 4/09