DEMO MANUAL DC1899A LTC4228-1/LTC4228-2 Dual Ideal Diode and Hot Swap Controller DESCRIPTION Demonstration circuit 1899A controls two independent power rail circuits each with Hot SwapTM and ideal diode functionality provided by the LTC4228-1/LTC4228-2 dual ideal diode and Hot Swap controller. DC1899A facilitates evaluation of LTC4228 performance in different operation modes such as supply ramp-up, power supply switchover, steady state, and overcurrent faults. Power supply switchover mode can be realized as either an ideal diode or as a prioritizer. Each DC1899A circuit is assembled to operate with a 12V supply and 9A maximum current load. The main components of the board are the LTC4228 controller, two MOSFETs operating as ideal diodes, two MOSFETs operating as Hot Swap devices, two current sense resistors, two jumpers for independently enabling each rail, six LEDs to PERFORMANCE SUMMARY SYMBOL PARAMETER VIN Input Supply Range VINTVCC(UVL) Internal VCC Undervoltage Lockout indicate status, power good and fault conditions separately for each channel, and input voltage snubbers. There are pads for optional RC circuits for each Hot Swap MOSFET gate in order to adjust output voltage slew rate. In addition to this there are jumpers allowing monitoring of supply undervoltage conditions at either IN or SENSE+ pins. The standard configuration (as DC1899A populated by default) places the ideal diode MOSFET ahead of the Hot Swap MOSFET. The board also has pads for an alternative configuration with the Hot Swap MOSFET located ahead of the ideal diode MOSFET. Design files for this circuit board are available at http://www.linear.com/demo L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and Hot Swap is a trademark of Linear Technology Corporation. All other trademarks are the property of their respective owners. Specifications are at TA = 25C CONDITIONS MIN TYP 2.9 INTVCC Rising MAX 18 UNITS V 2.1 2.2 2.3 V VINTVCC(HYST) Internal VCC Undervoltage Lockout Hysteresis Ideal Diode Control 30 60 90 mV VFWD(REG) Forward Regulation Voltage (VIN - VOUT) 10 25 40 mV VDGATE External N-Channel Gate Drive (VDGATE - VIN) VFWD = 0.1V IN < 7V IN = 7V to 18V 5 10 7 12 14 14 V V ICPO(UP) CPO Pull-Up Current CPO = IN = 2.9V CPO = IN = 18V -60 -50 -95 -85 -120 -110 A A IDGATE(FPU) DGATE Fast Pull-Up Current VFWD = 0.2V, VDGATE = 0V, CPO = 17V -1.5 A IDGATE(FPD) DGATEn Fast Pull-Down Current VFWD = -0.2V, VDGATE = 5V 1.5 A Hot Swap Control VSENSE(CB) Circuit Breaker Trip Sense Voltage (VSENSEEn+ - VSENSEEn-) 47.5 50 52.5 mV VSENSE(ACL) Active Current Limit Sense Voltage (VSENSEEn+ - VSENSEEn-) 55 65 75 mV IHGATE(UP) External N-Channel Gate Pull-Up Current Gate Drive On, HGATE = 0V -7 -10 -13 A IHGATE(DN) External N-Channel Gate Pull-Down Current Gate Drive Off, OUT = 12V, HGATE = OUT + 5V 150 300 500 A IHGATE(FPD) External N-Channel Gate Fast Pull-Down Current Fast Turn-Off, OUT = 12V, HGATE = OUT + 5V 100 200 300 mA dc1899af 1 DEMO MANUAL DC1899A PERFORMANCE SUMMARY SYMBOL PARAMETER Specifications are at TA = 25C CONDITIONS MIN TYP MAX UNITS Input/Output Pin VON(TH) ONn On Pin Threshold Voltage ON Rising 1.21 1.235 1.26 V VON(RESET) ONn Pin Fault Reset Threshold Voltage ON Falling 0.55 0.6 0.63 V VEN(TH) EN Pin Threshold Voltage EN Rising 1.185 1.235 1.284 V VTMR(TH) TMRn Pin Threshold Voltage TMR Rising TMR Falling 1.198 0.15 1.235 0.2 1.272 0.25 V V ITMR(UP) TMRn Pin Pull-Up Current TMR = 1V, In Fault Mode -75 -100 -125 A ITMR(DN) TMRn Pin Pull-Down Current TMR = 2V, No Faults ITMR(RATIO) TMRn Current Ratio ITMR(DN)/ITMR(UP) 1.4 2 2.6 A 1.4 2 2.7 % OPERATING PRINCINPLES The LTC4228 functions as an ideal diode with inrush current limiting and overcurrent protection by controlling two external back-to-back N-channel MOSFETs in a power path. The LTC4228 has two ideal diode and two Hot Swap controllers. Each ideal diode MOSFET is intended to operate with a defined Hot Swap MOSFET, because they are tied by common on/off control, and ideal diode controller sense voltage includes both MOSFETs and sense resistor voltage drop. Therefore, LTC4228 provides independent control for the two input supplies. The LTC4228 gate drive amplifiers monitor the voltage between the INn and OUTn pins and drive the DGATEn pins. The amplifier quickly pulls up the DGATE pin, turning on the MOSFET (Q1 or Q3), for ideal diode control when it senses a large forward voltage drop. Pulling the ON pin high and EN pins low initiates a 100ms debounce timing cycle. After this timing cycle, a 10A current source from the charge pump ramps up the HGATEn pin. When the Hot Swap MOSFET (Q2 or Q4) turns on, the inrush current is limited to a set level set by an external sense resistor placed between IN and SENSE pins. An active current limit amplifier servos the gate of the Hot Swap MOSFET to 65mV across the current sense resistor. Inrush current can be further reduced, if desired, by adding a capacitor from HGATE to GND. When the MOSFET's gate overdrive (HGATE to OUT voltage) exceeds 4.2V, the PWRGD pin pulls low. When both MOSFETs (Q1 and Q2 or Q3 and Q4) are turned on, the gate drive amplifier controls DGATE to servo the forward voltage drop (VIN - VOUT) across the sense resistor and the back-to-back MOSFETs to 25mV. If the load current causes more than 25mV of voltage drop, the gate voltage rises to enhance the MOSFET used for ideal diode control. For large output currents the MOSFET's gate is driven fully on and the voltage drop is equal to the sum of the ILOAD * RDS(ON) of the two MOSFETs in series. In the case of an input supply short-circuit when the MOSFETs are conducting, a large reverse current starts flowing from the load towards the input. The gate drive amplifier detects this failure condition as soon as it appears and turns off the ideal diode MOSFET by pulling down the DGATE pin. dc1899af 2 DEMO MANUAL DC1899A QUICK START PROCEDURE Demonstration circuit 1899A can be easily set up to evaluate the performance of the LTC4228-1/LTC4228-2. Refer to the Figure 1 for proper measurement equipment setup and follow the procedure below. The DC1899A test includes independent tests of the LTC4228 Hot Swap functionality, ideal diode functionality and two power rails prioritizer functionality with the channel 1 highest priority. HOT SWAP FUNCTIONALITY TEST This test is identical for each 12V rail and is performed in the three steps by the measuring of the transient's parameters in the different operation modes. Install the jumpers in the following positions: JP4, RON1_SEL and JP5, RON2_SEL in position OFF; JP1, EN1_SEL and JP2, EN2_SEL in position LOW. RL1 CL1 PSU SW1 RL2 SW2 CL2 PSU SW3 SW4 Figure 1. Measurement Equipment Setup for Hot Swap Functionality Test dc1899af 3 DEMO MANUAL DC1899A QUICK START PROCEDURE No-Load Rampup Current Limit Connect a 12V power supply to the board input turrets IN1 (IN2) and GND. Do not load the output. Place current probe on the 12V supply and voltage probes on the OUT1 (OUT2) turret. Provide ON1 (ON2) signal at the ON1 (ON2) pin by moving the RON1_SEL (RON2_SEL) jumper from OFF position to the 12V position. Observe the transient. The output voltage rise time should be in the range of 12ms to 29ms. PWRGD1 (PWRGD2) green LED should be lit. Turn off the rail using the RON1_SEL (RON2_SEL) jumper. Initially adjust an electronic resistive load to 10 to 12 and connect it to the OUT1 (OUT2) turret and GND. Turn on the rail and slowly increase load current up to the circuit breaker threshold level. The current limit range should be between 9A and 12.3A. Turn off the rail using the RON1_SEL (RON2_SEL) jumper. VOUT INPUT CURRENT dn1899a F02 Figure 2. Turn-On Output Transient Test CURRENT LIMIT AT 10A CURRENT 2A/DIV OUTPUT VOLTAGE DROPPING DUE TO SHUTDOWN dn1899a F03 Figure 3. Current Limiting Test dc1899af 4 DEMO MANUAL DC1899A QUICK START PROCEDURE Power-Up into Output Short Short the output to ground with a wire. Place the current probe on this wire. Turn on the rail and record the current shape. The maximum current should be in the 11.6A to 16.9A range. The LTC4228-1 latches off after overcurrent condition, but the LTC4228-2 automatically retries after 200ms to 450ms. IDEAL DIODE FUNCTIONALITY TEST Use an individual 12V power supply for each rail; connect the two outputs together at a common load. Adjust each input voltage to 12V with maximum possible accuracy. In this test, both rails are active and small variations in the input voltage will force one channel off and the other channel on. Place a voltmeter between IN1 and IN2 turrets to measure the difference between two input voltages. Activate both rails and keep a load around 1A to 3A. Adjust the input voltage level of one supply such that IN1 is 40mV more positive than IN2. Verify that only channel 1 is drawing current. Repeat this test with IN1 at -40mV with respect to IN2. In this case channel only channel 2 is drawing current. PRIORITIZER FUNCTIONALITY TEST The DC1899A is assembled with components to implement a power prioritizer with channel 1 having the higher priority. Place JP7 PPR_SEL (power priority select) jumper in position ON2 and JP5 RON2_SEL (ON2 select) in position OFF. Apply independent supply voltages (12V) to both inputs. Channel 1 will be connected to load. Reduce channel 1 input voltage until it reaches an undervoltage condition and D6 (PWRGD2) lights. At the same time channel 2 power supply will deliver power to the load. CURRENT PROFILE DURING SHORT-CIRCUIT TURN-ON dn1899a F04 Figure 4. Short-Circuit Test (2A/Div) dc1899af 5 DEMO MANUAL DC1899A PARTS LIST ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER Required Circuit Components 1 7 C1, C2, C3, C8, C9, C11, C14 CAP., X7R, 0.1F, 50V, 0603 AVX, 06035C104KAT 2 2 C4, C5 CAP., X7R, 47nF, 50V, 0603 AVX, 06035C473KAT 3 2 C6, C7 CAP., X7R, 15nF, 50V, 0603 AVX, 06035C153KAT 4 0 C10, C12, C13, C15 CAP., ALUMINUM, 100F 50V, OPT SANYO, 50CE100BS 5 2 D1, D2 DIODE, VOLTAGE SUPP. 19V 5%, SMA-DIODE VISHAY, SMAJ17A-E3 6 4 D3, D5, D6, D8 LED, SMT GREEN, J TYPE, LED-LN1351C-GREEN PANASONIC, LN1351C-TR 7 2 D4, D7 LED, SMT RED, GW TYPE, LED-LN1261C-RED PANASONIC, LN1261C-TR 8 1 D9 DIODE, SWITCHING, SOD80 VISHAY, LS4148-GS18 9 0 D10, D11, D12, D13 DIODE, CMHZ4706, SOD123 OPT 10 8 E1, E2, E3, E4, E5, E6, E7, E8 TP, 0.094" MILL-MAX, 2501-2-00-80-00-00-07-0 11 12 E9, E10, E11, E13-E16, E18-E22 TP, 0.064" MILL-MAX, 2308-2-00-80-00-00-07-0 12 5 JP1, JP2, JP3, JP6, JP7 JMP, HD1X3, 0.079CC SAMTEC, TMM-103-02-L-S 13 2 JP4, JP5 JMP, HD2X4, 0.079CC SAMTEC, TMM-104-02-L-D 14 8 J1, J2, J3, J4, J5, J6, J7, J8 JACK, BANANA KEYSTONE, 575-4 15 4 Q1, Q2, Q3, Q4 MOSFET, N-CH, 30-V, SO8-POWERPAK VISHAY, SiR158DP 16 0 Q5, Q6, Q7, Q8 MOSFET, N-CH, 30-V, SiR158DP, SO8-POWERPAK OPT 17 2 RS1, RS2 RES., CHIP, 0.005, 1/2W, 1%, 2010 VISHAY, WSL20105L000FEA 18 0 RS3, RS4 RES., CHIP, 0.005, 1/2W, 1%, 2010, OPT VISHAY, WSL20105L000FEA 19 4 R1, R3, R19, R20 RES., CHIP, 10, 1%, 0603 VISHAY, CRCW060310R0FKEA 20 2 R2, R4 RES., CHIP, 47, 1%, 0603 VISHAY, CRCW060347R0FKEA 21 6 R5, R6, R7, R8, R9, R10 RES., CHIP, 3k, 1%, 0805 VISHAY, CRCW08053K00FKEA 22 2 R11, R15 RES., CHIP, 20k, 1%, 0603 VISHAY, CRCW0060320K0FKEA 23 2 R12, R16 RES., CHIP, 137k, 1%, 0603 VISHAY, CRCW0603137KFKEA 24 2 R13, R17 RES., CHIP, 49.9k, 1%, 0603 VISHAY, CRCW060349K9FKEA 25 2 R14, R18 RES., CHIP, 28k, 1%, 0603 VISHAY, CRCW0060328K0FKEA 26 0 R21, R25 RES., CHIP, 10, 0603 OPT 27 0 R22, R26 RES., CHIP, 0, 0603 OPT 28 1 R23 RES., CHIP, 470, 1%, 0603 VISHAY, CRCW0603470RFKEA 29 1 R24 RES., CHIP, 41.2k, 1%, 0603 VISHAY, CRCW0060341K2FKEA I.C. LTC4228IUFD-1, QFN28UFD LINEAR TECH., LTC4228IUFD-1 I.C. LTC4228IUFD-2, QFN28UFD LINEAR TECH., LTC4228IUFD-2 DC1899A-A Assembly 2 1 U1 DC1899A-A Assembly 2 1 U1 dc1899af 6 Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no representation that the interconnection of its circuits as described herein will not infringe on existing patent rights. A B C J5 E5 J7 E7 E6 E18 GND GND E8 J8 ON2 ON1 VIN2 VS2+ 5 JP5 HD2X4-079 RON2_SEL 1 2 3 4 5 6 7 8 JP4 HD2X4-079 RON1_SEL 1 2 3 4 5 6 7 8 C11 0.1uF 50V R19 10 12V 5V 3.3V OFF R16 137k 1% D2 SMAJ17A C14 0.1uF 50V R20 10 R17 49.9k 1% HG1 DG1 DG2 HG2 R18 28k 1% C9 0.1uF 50V R12 137k 1% R15 20K 1% R13 49.9k 1% C8 0.1uF 50V R14 28k 1% R11 20K 1% 12V 5V 3.3V OFF THICK TRACE WIDTH > 500 MIL SENSE2+ IN2 100uF 50V OPT IN2 + C13 JP6 VON2_SEL 1 2 3 E10 E11 E9 D1 SMAJ17A THICK TRACE WIDTH > 500 MIL SENSE1+ IN1 100uF 50V OPT + C10 IN1 VON1_SEL 1 2 3 VIN1 JP3 VS1+ 2.9V - 18V IN2 IN2 ON2 GND PROBE GND ON1 GND GND J6 2.9V - 18V IN1 IN1 50V C1 0.1uF 4 ON1 INTVCC ON2 50V C3 0.1uF 16 29 5 EP GND 21 4 50V Q3 SiR158DP INTVCC C2 0.1uF Q1 SiR158DP SENSE1+ R22 0 OPT DG1 1 SENSE2+ RS2 0.005 0.5W 2010 2010 RS4 OPT 0.5W 0.005 R26 0 OPT * QFN28UFD-4X5 U1 RS1 0.005 0.5W 2010 2010 RS3 OPT 0.5W 0.005 HG1 D 4 IN1 CPO2 10 2 1 2 27 CPO1 3 SENSE1+ DGATE1 2 SENSE1+ 28 IN1 IN2 6 IN2 DGATE2 9 DG2 SENSE2+ SENSE2+ 7 Q5 SiR158DP OPT DG2 HG2 Q7 SiR158DP OPT Q4 SiR158DP TMR2 PWRGD2 FAULT2 STATUS2 EN2 EN1 STATUS1 FAULT1 PWRGD1 TMR1 R1 10 Q2 SiR158DP HG1 DG1 OUT1 24 SENSE11 SENSE2- 8 OUT1 25 SENSE1SENSE2- HGATE1 HGATE2 12 HG2 OUT2 13 OUT2 1 C7 15nF 50V R3 10 C5 47nF 16V C4 47nF 16V 50V C6 15nF R4 47 18 14 15 11 17 20 26 22 23 19 R2 47 D10 CMHZ4706 OPT R21 10 OPT D12 CMHZ4706 OPT R25 10 OPT 3 3 D13 CMHZ4706 OPT R8 3K 0805 D6 LN1351C GREEN E1 OUT1 PPR_SEL ON2 GND GND OUT1 ADJ., 9A E21 E22 E20 E19 E15 E16 E4 J4 J3 E3 ON2 GND GND OUT2 ADJ., 9A OUT2 PWRGD2 FAULT2 STATUS2 STATUS1 FAULT1 PWRGD1 OFF JP7 HD1X3-079 3 2 1 E2 J2 J1 CUSTOMER NOTICE C15 + 100uF 50V OPT OUT2 D9 LS4148 R23 470 R24 41.2k INTVCC C12 + 100uF 50V OPT OUT1 2 E14 E13 JP2 2 THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS. SCALE = NONE EN2 EN1 __ ECO 1 REV 1 1ST PROTOTYPE DESCRIPTION VLADIMIR O. APPROVED REVISION HISTORY * U1 LTC Confidential-For Customer Use Only 1630 McCarthy Blvd. Milpitas, CA 95035 Phone: (408)432-1900 www.linear.com TECHNOLOGY Fax: (408)434-0507 LTC4228IUFD-1 LTC4228IUFD-2 DATE 10-25-11 DATE: B SIZE LTC4228IUFD-1/-2 1 DEMO CIRCUIT 1899A 10/25/2011, 04:28 PM IC NO. SHEET 1 OF 1 1 REV. DUAL IDEAL DIODE AND HOT SWAP CONTROLLER TITLE: SCHEMATIC -A -B ASSY 1. ALL RESISTORS ARE IN OHMS, 0603. ALL CAPACITORS ARE IN MICROFARADS, 0603. NOTE: UNLESS OTHERWISE SPECIFIED EN2_SEL EXT LOW JP1 EN1_SEL EXT LOW APPROVALS 3 2 1 3 2 1 LINEAR TECHNOLOGY HAS MADE A BEST EFFORT TO DESIGN A CIRCUIT THAT MEETS CUSTOMER-SUPPLIED SPECIFICATIONS; HOWEVER, IT REMAINS THE CUSTOMER'S RESPONSIBILITY TO PCB DES. KIM T. VERIFY PROPER AND RELIABLE OPERATION IN THE ACTUAL APP ENG. VLADIMIR O. APPLICATION. COMPONENT SUBSTITUTION AND PRINTED CIRCUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT PERFORMANCE OR RELIABILITY. CONTACT LINEAR TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE. SENSE2+ R10 3K 0805 D8 LN1351C GREEN D5 LN1351C GREEN R7 3K 0805 SENSE1+ Q8 SiR158DP OPT R9 3K 0805 D7 LN1261C RED D4 LN1261C RED R6 3K 0805 R5 3K 0805 D3 LN1351C GREEN Q6 SiR158DP OPT D11 CMHZ4706 OPT 1 2 2 1 2 1 2 1 2 2 1 1 2 2 1 1 2 2 1 2 1 5 A B C D DEMO MANUAL DC1899A SCHEMATIC DIAGRAM dc1899af 7 DEMO MANUAL DC1899A DEMONSTRATION BOARD IMPORTANT NOTICE Linear Technology Corporation (LTC) provides the enclosed product(s) under the following AS IS conditions: This demonstration board (DEMO BOARD) kit being sold or provided by Linear Technology is intended for use for ENGINEERING DEVELOPMENT OR EVALUATION PURPOSES ONLY and is not provided by LTC for commercial use. As such, the DEMO BOARD herein may not be complete in terms of required design-, marketing-, and/or manufacturing-related protective considerations, including but not limited to product safety measures typically found in finished commercial goods. As a prototype, this product does not fall within the scope of the European Union directive on electromagnetic compatibility and therefore may or may not meet the technical requirements of the directive, or other regulations. If this evaluation kit does not meet the specifications recited in the DEMO BOARD manual the kit may be returned within 30 days from the date of delivery for a full refund. THE FOREGOING WARRANTY IS THE EXCLUSIVE WARRANTY MADE BY THE SELLER TO BUYER AND IS IN LIEU OF ALL OTHER WARRANTIES, EXPRESSED, IMPLIED, OR STATUTORY, INCLUDING ANY WARRANTY OF MERCHANTABILITY OR FITNESS FOR ANY PARTICULAR PURPOSE. EXCEPT TO THE EXTENT OF THIS INDEMNITY, NEITHER PARTY SHALL BE LIABLE TO THE OTHER FOR ANY INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES. The user assumes all responsibility and liability for proper and safe handling of the goods. Further, the user releases LTC from all claims arising from the handling or use of the goods. Due to the open construction of the product, it is the user's responsibility to take any and all appropriate precautions with regard to electrostatic discharge. Also be aware that the products herein may not be regulatory compliant or agency certified (FCC, UL, CE, etc.). No License is granted under any patent right or other intellectual property whatsoever. LTC assumes no liability for applications assistance, customer product design, software performance, or infringement of patents or any other intellectual property rights of any kind. LTC currently services a variety of customers for products around the world, and therefore this transaction is not exclusive. Please read the DEMO BOARD manual prior to handling the product. Persons handling this product must have electronics training and observe good laboratory practice standards. Common sense is encouraged. This notice contains important safety information about temperatures and voltages. For further safety concerns, please contact a LTC application engineer. Mailing Address: Linear Technology 1630 McCarthy Blvd. Milpitas, CA 95035 Copyright (c) 2004, Linear Technology Corporation dc1899af 8 Linear Technology Corporation LT 0812 * PRINTED IN USA 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 www.linear.com (c) LINEAR TECHNOLOGY CORPORATION 2012