Vicor PI2121-EVAL1 User Manual

Picor Corporation • www.picorpower.com PI2121-EVAL1 User Guide Rev 1.1 Page 1 of 12

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.

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

Cool-ORing™ Series

PI2121-EVAL1 Full-Function Active ORing

Evaluation Board User Guide

®

Contents

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

PI2121-EVAL1 Evaluation Board
featuring the Cool-ORing PI2121
Full-Function Active ORing Solution.

Cool-ORing™ Series

The PI2121-EVAL1 Evaluation Board is intended to acquaint the

user with the benefits and features of the Cool-ORing

TM

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.

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.

Picor Corporation • www.picorpower.com PI2121-EVAL1 User Guide Rev 1.1 Page 2 of 12

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.

Figure 1 – PI2121-EVAL1 Evaluation Board (1.8" x 1.8")

Terminals Rating

Vin1, Vin2 8V / 24 A
Vaux1, Vaux2, (R7 = R14 = 10 Ω)

-0.3 to 17.3 V / 40 mA

see Vaux section

SL -0.3 to 8.0 V / 10 mA

FT -0.3 to 17.3 V / 10 mA

Terminal Description
Vin1 Power Source Input #1 or bus input designed to accommodate up to 24 A continuous current.
Vaux1 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.

Rtn1 Vaux1 Return Connection: Connected to Ground plane
Gnd 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.

SL1 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.

SL2 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.

Vin2 Power Source Input #2 or bus input designed to accommodate up to 24 A continuous current.
Vaux2 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.

Rtn2 Vaux2 Return Connection: Connected to Ground plane
FT1 PI2121 (SiP1) Fault Pin: Monitors SiP1 fault conditions
FT2 PI2121 (SiP2) Fault Pin: Monitors SiP2 fault conditions
Vout Output: SiP1 and SiP2 D pins connection, connect to the load high side.

Table 1 – PI2121-EVAL1 Evaluation Board terminals description

Cool-ORingTMPI2121 Product Description

Jumper Description
J1, J3 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.

J2 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 3 of 12

Vin1

Figure 2 – PI2121-EVAL1 Evaluation Board schematic.

Item QTY Reference Designator Value Description Footprint Manufacturer

1 2 C1, C2 1 µF

Capacitor, MLCC X5R,

0603

1 µF,16 V

2 1 C3 22 µF

Capacitor, MLCC X7R,

1210

22 µF, 25 V
3 4 C4, C5, C6, C7 Not installed 1206
4 2 D1, D2 LED, Super Red THIN 0603 Lite-On, Inc.,

58

FT1, FT2, Rtn1, Rtn2,

Turret Test point TURRET-1528

Keystone

SL1, SL2, Vaux1, Vaux2 Electronics

67

Gnd1, Gnd2, Gnd3, Gnd4,

Turret Test point TURRET-1502

Keystone

Vin1, Vin2, Vout1, Vout2 Electronics
7 2 J1, J3 Header Pins 0.1" pitch 2 x 3mm
8 1 J2 Header Pins 0.1" pitch 2 x 2mm
9 2 R1, R8 8.45 KΩ Resistor, 8.45 KΩ, 1% 0603

10 2 R2, R9 13.3 KΩ Resistor,13.3 KΩ,1% 0603
11 4 R3, R4, R10, R11 2.00 KΩ Resistor, 2.00 KΩ,1% 0603
12 2 R5, R12 4.99 KΩ Resistor, 4.99 KΩ,1% 0603
13 2 R6, R13 Not Installed 0603
14 2 R7, R14 10 Resistor, 10, 5% 0603

15 2 SiP1, SiP2 PI2121

Picor Full-Function 24 A

5x7mm;17 pins PICOR

Cool-ORing Solution

Table 3 – PI2121-EVAL1 Evaluation Board bill of materials

GND

8.45 K 1%

GND

Vaux1 Vaux1

Rtn1

SL1

2.00 K 1%

SL1

Vin1

R1 R2

UV1 OV1

R3 R4

13.3 K 1%

2.00 K 1%

D1

LTST-C191KRKT

C4
NP

4.99 K

SIP1
PI2121

GND

OV1

C1
1 uF

D
D
D
D

SN

UV

OV

VC1

1
17
16
15

14

13

2

S

3

S

4

S

5

FT1

FT1

R5

S

6

SP

7

FT

BK1

R6
NP

BKSLVC

8

9

SL1

101112

VC1

J1

Vout

C6
NP

UV2

Vout1

Vout2

C3
22 uF

GND3

GND4

OV2

Vaux2

Vaux1

R7

10 Ω

R9

13.3 K 1%

R11

2.00 K 1%

D2

LTST-C191KRKT

R7

10 Ω

C5
NP

R12

4.99 K

FT2

FT2

J3

VC2

2
3
4
5

6

7

BK2

R13

NP

S
S
S
S

SP

FT

BKSLVC

8

SIP2
PI2121

9

SL2

GND

101112

OV2

1

D

17

D

16

D

15

D

14

SN

13

UV

OV

UV2

VC2

C2
1 µF

NP: Not Populated
C4, C5, C6, C7, R6 and R13

C7
NP

SL2

SL2

Vin2

Q1

GND

8.45 K 1%

GND

Vaux2 Vaux2

Rtn2

2.00 k 1%

J2

Vin2

R8

UV2

R10

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 Two DC power supplies - 0-10 V; 25 A.

1.2 DC power supply 12 V; 100 mA.

1.3 DC electronic load - 50 A minimum.

1.4 Digital Multimeter

1.5 Oscilloscope.

1.6 Appropriately sized interconnect cables.

1.7 Safety glasses.

1.8 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

Reference Designator Value Functional Description

C1, C2 1µF VC Bypass Capacitor
C3 22µF Output (Load) Capacitor
C4, C5, C6, C7 Not installed Snubber to reduce voltage ringing when the device turns off
D1, D2 LED To indicate a fault exist when it is on
J1, J3 Jumper To select between Master and Slave Modes
J2 Jumper Connection between SL1 and SL2
R1, R8 8.45KΩ UV Voltage Divider Resistor ( R2UVin Figure 4)
R2, R9 13.3KΩ OV Voltage Divider Resistor ( R2OVin Figure 4)
R3, R10 2.00KΩ UV Voltage Divider Resistor ( R1UVin Figure 4)
R4, R11 2.00KΩ OV Coltage Divider Resistor ( R1

OV

in Figure 4)
R5, R12 4.99KΩ LED Current Limiter
R6, R13 Not Installed BK Delay Timer Programmable Resistor
R7, R14 10Ω VC Bias Resistor
SiP1, SiP2 PI2121 Cool ORing SiP.

Table 4 – Component functional description