PI2127-EVAL1 Cool ORing® Series PI2127-EVAL1 60V/12A Full-Function High Side Active ORing Evaluation Board User Guide Content Cool-ORing® Series Page Introduction ................................................................ 1 Product Description ................................................... 2 Schematic. ................................................................. 3 Bill of Material ............................................................ 3 Test Procedure: ......................................................... 4 Recommended Material ............................................... 4 Thermal Imaging: ....................................................... 7 PCB Layout ............................................................... 8 PI2127-EVAL1 Evaluation Board featuring the Cool-ORing PI2127 Full-Function Active ORing Solution. Mechanical Drawing .................................................. 8 The PI2127-EVAL1 Evaluation Board is intended to acquaint the user with the benefits and features of the ® Cool-ORing PI2127 full-function Active ORing solution. It is not designed to be installed in end-use equipment. Please read this document before setting up the PI2127EVAL1 Evaluation Board and refer to the PI2127 product datasheet 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. Introduction The PI2127-EVAL1 allows the user to test the basic principles and operational characteristics of an Active ORing function in a redundant power architecture, while also experiencing the benefits and value of the PI2127 solution versus conventional Active ORing solutions. The PI2127-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 12A, and is suitable redundant bus voltages up to 48V. The PI2127-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 48V BUS applications Picor Corporation • picorpower.com requiring up to 12A. This evaluation board is intended as an easy and simple way to test the electrical and thermal performance of the PI2127 Full-Function Active ORing solution. Both dynamic and steady state testing of the PI2127 can be completed on the PI2127-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 startup and configuration of the evaluation board. Further information on the functionality of the PI2127 can be found in the PI2127 product datasheet. PI2127-EVAL1 User Guide Rev. 1.0 Page 1 of 9 ® Cool-ORing PI2127 Product Description ® The PI2127 Cool-ORing 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 PI2127 Cool-ORing® solution is offered in an extremely small, thermally enhanced 7mm x 8mm LGA package and can be used in high side, medium voltage Active ORing applications. The PI2127 enables extremely low power loss with fast dynamic response to fault conditions, critical for high availability systems. The PI2127, with its 60V/8.5mΩ internal MOSFET provides very high efficiency and low power loss during steady state operation, while achieving high-speed turnoff of the internal MOSFET during input power source fault conditions that cause reverse current flow. The PI2127 provides an active low fault flag output to the system during reverse current, excessive forward overcurrent and UVLO fault conditions. Figure 1: PI2127-EVAL1 Evaluation Board (1.8” x 1.8”) Terminals Maximum Rating. 60V/12A Vout+ 60V/24A 1, Figure 1 shows a photo of the PI2127-EVAL1 evaluation board, with two PI2127 SiPs 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 PI2127 Cool-ORing® solution. Terminal Vin1+, Vin2+, 20V / 10mA 2 VL1, VL2 (R5=R6=1.5kΩ)* 5.5V * VL1, VL2 voltage can be raised , but R5 and R6 values have to be increased to accommodate the LEDs Description Vin1+ Power source Input #1: or bus input designed to accommodate up to 60V and 12A continuous current. Vin1- Vin1+ return connection Vin2+ Power source Input #2: or bus input designed to accommodate up to 60V and 12A continuous current. Vin2- Vin2+ return connection 1 PI2127 (U1) Fault pin: referenced to the Gnd terminal (Vin1-) 2 PI2127 (U2) Fault pin: referenced to the Gnd terminal (Vin2-) EN1 PI2127 (U1) Enable: leave open to enable the U1 and connect to return (Vin1-) to disable U1 EN2 PI2127 (U2) Enable: leave open to enable the U2 and connect to return (Vin2-) to disable U2 Vout+ Output: U1 and U2 D pins connection, connect to the load high side. Vout- Vout+ return connection Note: Vin1-, Vin2- and Vout- are connected to the same point at the PCB bottom layer Table 1: PI2127-EVAL1 Evaluation Board Terminals Description Picor Corporation • picorpower.com PI2127-EVAL1 User Guide Rev. 1.0 Page 2 of 9 Figure 2: PI2127-EVAL1 Evaluation Board schematic. Item Reference Designator Value Footprint C1, C2, C3, C4 2 C5 22uF Electrolytic 22uF,100V 3 C6 2.2uF MLCC 2.2uF,100V 4 D1, D2 LTST-C191CKT LED, Red 0603 LED Lite-On 5 D3, D4 BZX384-B6V8 Zener, 6.8V,300mW SOD-323 NXP 6 EN1, EN2, VL2 7 Vin1+, Vin1-, Vin2+, Vin2-, Vout+, Vout- 8 2, VL1, MLCC, X7R,1uF,50V Manufacturer 1 1, Not Installed Description 1206 Panasonic _E/F Panasonic 1812 1528 Turret Test point TURRET - 1528 Keystone Electronics 1502 Turret Test point TURRET - 1502 Keystone Electronics Q1, Q2 FJV1845 NPN,120V,50mA SOT-23 9 R1, R2 Not Installed 10 R3, R4 2.8K Resistor,2.8K,1% 0603 11 R5, R6 1.5K Resistor,1.5K,1% 0603 12 R7, R8 100K Resistor,100K,1% 0805 13 U1, U2 PI2127-01-LGIZ Fairchild 1206 12A 60V Full-Function Cool-ORing® Solution 7mm x 8mm 17 pin PICOR Table 2: Complete PI2127-EVAL1 Evaluation Board Bill of Material Picor Corporation • picorpower.com PI2127-EVAL1 User Guide Rev. 1.0 Page 3 of 9 Reference Designator C1, C2, C3, C4 Value Not installed Functional Description Snubber to reduce voltage ringing when the device turns off C3 22μF Output (Load) Capacitor C6 2.2uF Output (Load) Capacitor D1, D2 LED To indicate a fault exists when it is on Q1, Q2 FJV1845 R1, R2 Not Installed R3, R4 2.8K R5, R6, 1.5KΩ LED current limit resistor, selected to operate at 3.3V and 5.0V logic voltage. Replace R5 and R6 with the proper resistor value for different logic voltage. R7, R8 100K Constant Current bias circuit U1, U2 PI2127-01-LGIZ Constant Current bias circuit Bias Circuit RPG, replaces constant current circuit Constant Current bias circuit, sets the current limiting Cool-ORing® SiP. Table 3: Component functional description Test Procedure: Initial Test Set Up PI2127-EVAL1 designed with two bias circuit options, bias resistor RPG (R1 and R2) and constant current circuit. The constant current circuits are installed; where R1 and R2 were not installed. Before initial power-up follow these steps to configure the evaluation board for specific end application requirements: 2. 2.1. Enable inputs (EN1 and EN2) were left unconnected (open). PI2127 devices will be enabled while enable pins are open. To disable PI2127, connecting the enable input to return (Vin-) with a hard wire or with an active device (Transistor or MOSFET). Leave EN1 and EN2 unconnected for the initial test. Leave enable inputs (EN1 and EN2) unconnected (open). Baseline Test Procedure – PI2127 (Refer to Figure 3) 1. Recommended Material 1.1. Material Needed-Picor supplied 1.1.1. PI2127-EVAL1 1.1.2. PI2127 Product Datasheet 1.2. Recommended Users Supplied Equipment 1.2.1. Two DC power supplies: 0-60V; 15A each. 1.2.2. One low power logic voltage power supply 1.2.3. Load: electronic Load, Power resistors or actual load. 1.2.4. Multimeter. 1.2.5. Oscilloscope. 1.2.6. Appropriately sized interconnect cables. 1.2.7. Safety glasses. Picor Corporation • picorpower.com EN inputs: 3. Control Circuitry Bias: 3.1. The PI2127 control circuitry and the gate driver for the internal MOSFET are biased through the S pin. An internal regulator clamps the S pin voltage with respect to PG pin (VS-PG) to 11.7V typically. A bias resistor (RPG) or a Constant Current bias circuit is required if the voltage at the S pin is higher than the minimum Voltage Clamp (VS-CLM, 11V). PI2127-EVAL1 has both circuits laid out, but the constant current bias circuit components are installed while RPG is not installed. PI2127-EVAL1 User Guide Rev. 1.0 Page 4 of 9 RDS(on) V S1 D1 + PS1 - 0-60V/15A + DC Electronic Load - Logic PS + PS3 12V/100mA S2 D2 + 25A PS2 - 0-60V/15A Figure 3: Layout configuration for typical redundant power application, using PI2127-01-LGIZ 3.2. If RPG is desired instead of the Constant Current bias circuit, remove the Constant Current bias circuit components from the evaluation board. The upper ORing (U1) constant current bias circuit components are Q1, R3, R7 and D3. The lower ORing (U2) constant current bias circuit components are Q2, R4, R8 and D4. RPG value can using the following equations: And RPG maximum power dissipation is: Where: : : : Minimum applied input voltage (Vin to Rtn) Maximum applied input voltage (Vin to Rtn) : Controller maximum clamp voltage, 12.5V : Controller minimum clamp voltage, 11V Controller maximum bias current, use 2.0mA RPG calculation example Vin (minimum) = 40V and Vin (maximum) = 50V Picor Corporation • picorpower.com 4. Hook Up of the Evaluation Board 4.1. Connect the positive terminal of PS1 power supply to Vin1+. Connect the ground terminal of PS1 to Vin1-. Set the power supply to 48V. Keep PS1 output disabled, off. 4.2. Connect the positive terminal of PS2 power supply to Vin2+. Connect the ground terminal of PS2 to Vin2-. Set the power supply to 48V. Keep PS2 output disabled, off. 4.3. Connect the logic power supply PS3 positive terminal to VL1 and VL2. Connect the ground terminal of this power supply to either Vin1- or Vin2-. Set the power supply to the desired logic voltage level, 3.3V or 5V. Keep PS3 output disabled, off. 4.4. Connect the electronic load to the output between Vout+ and Vout-. Set the load current to 5A. 4.5. Enable (turn on) PS3 power supply output. 4.6. Enable (turn on) PS1 power supply output. 4.7. Turn on the electronic load. 4.8. Verify that Vout+ voltage is a few millivolts below 48V. This verifies that the PI2127 (U1) internal MOSFET is in conduction mode. 4.9. Verify that Vin2+ is low. This verifies that the PI2127 (U2) internal MOSFET is off. PI2127-EVAL1 User Guide Rev. 1.0 Page 5 of 9 4.10. 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+). 4.11. Enable (turn on) PS2 output. 4.12. Verify that both PS1 and PS2 are sharing load current evenly by looking at the supply current. Power supplies output may need adjustment to set current sharing between the supplies. 4.13. Disable (turn off) PS1, PS2, and PS3 outputs. 4.14. Enable (turn on) PS2 output then Enable and PS3 outputs. 4.15. Verify that the electronic load voltage reading is few millivolts below 48V. This verifies that the PI2127-01-LGIZ internal MOSFET is in conduction mode. 4.16. D2 should be off. This verifies that there is no fault condition. 4.17. Verify that Vin1+ is low. This verifies that the PI2127 (U1) internal FET is off. 4.18. 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+). Note: When the PI2127 internal MOSFET is in the on state, it will not turn off unless a reverse current greater than 0.75A is sensed in the MOSFET. When both power supplies are enabled and both PI2127 MOSFETs are in RDS(on); if one of the sources (Power supplies) removed or disabled both PI2127 stay on unless the disabled power supply sources current greater than 0.75A when turned off. 5. Internal MOSFET RDS(on) Measurement: 5.1. The internal MOSFET RDS(on) can be measured with a voltmeter between the S1 and D1 Kelvin connection for U1 and between the S2 and D2 Kelvin connection for U2. The potential between S1 and D1 is the voltage drop across the internal MOSFET and: Where: : Voltage drop MOSFET across Picor Corporation • picorpower.com the : Input current. Note: The RDS(on) value is temperature dependent and the junction temperature increases directly proportional to power dissipation. 6. Input short circuit test: PI2127 has a very fast response (80ns) to a reverse current (Input short) fault condition. Measuring a short period event requires attention to the test set-up. Before proceeding, consider the following: 6.1. To emulate a real application, the BUS supplies for this test should have a solid output source such as a 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 PI2127 will be used. Typical bench power supplies have slow response to output load change. In this test when the power supply output is shorted and then released, the bench power supply may produce high output voltage with high current capability that may damage the device under test. 6.2. Do not install Input capacitors (C1 and/or C2) in this test. 6.3. Output capacitor (C5) should be installed. 6.4. Place the scope probes very close to the PI2127 S and D pins to measure Vin and Vout, and make sure that the scope ground leads are very short. You may use a close by ground pad for the scope probe return, such as C1, C2, C3 and C4 return pads. 6.5. Apply a short at one of the inputs (Vin1+ or Vin2+) when both SIP’s (U1 and U2) are on, PS1 and PS2 are enabled. The short can be applied electronically using a MOSFET connected between Vin+ and Vin- or simply by connecting Vin+ to Vin-. Then measure the response time between when the short is applied and the PI2127 internal MOSFET is disconnected (or turned off). An example for the PI2127 response time to an input short circuit is shown in Figure 4. internal PI2127-EVAL1 User Guide Rev. 1.0 Page 6 of 9 Test Setup: DUT: PI2127-EVAL1 Vin1+ = 48V Vin2+ = 48V Output Load = 5A Test: Both input sources are turned on and sharing the load current, then applied a short with a screw driver between Vin1+ and Vin1-. Test purpose: To show the PI2127 response to a fault condition, where the output of the input source is shorted or tried to source current from the load (Vout). Figure 4: Plot of PI2127 response time to reverse current detection Thermal Imaging: MOSFET MOSFET PI2127 PI2127 Figure 5 PI2127 mounted on PI2127-EVAL1, Iout=12A, TA=25°C, Air Flow=0LFM Figure 6: PI2127 mounted on PI2127-EVAL1, Iout=12A, TA=25°C, Air Flow=200LFM Picor Corporation • picorpower.com PI2127-EVAL1 User Guide Rev. 1.0 Page 7 of 9 PCB Layout Figure 7: PI2127-EVAL1 layout top layer. Scale 2.0:1 Figure 8: PI2127-EVAL1 layout bottom layer 2. Scale 2.0:1 Mechanical Drawing Figure 9: PI2127-EVAL1 evaluation board mechanical drawing. Picor Corporation • picorpower.com PI2127-EVAL1 User Guide Rev. 1.0 Page 8 of 9 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 PI2127-EVAL1 User Guide Rev. 1.0 Page 9 of 9