NCP1565TELECGEVB

Test Procedure for the NCP1565 3.3-V/20-A Dc-dc Converter 1 Christophe Basso – March 2014 Board Electrical Schematic D2a BAV23CL L3 660uH Vcc 18 D O1606C T-684 D2b BAV23CL 12 T1 Payton 1. + Vin - R6 10 J1a 36-75 V + R23a 2.2 8 V in R23b 2.2 C1 C2 C3 C4 R1 51k 40 EN Mill-Max 3104-2-00-80-00-00-08-0 J3a J3b J1c on/off jumper R45 10 100 V R3 75k - Group of components close to the IC R4 2k CS R32 7.5 51 24 ra m p 1 42 36 SS Vin NC NC 23 22 21 20 2 DT 4 RT 5 1 5 P Gn d NCP1565 C14 22nF R5 13k R8 66k 7 R31 19.8k c om p 53 DT limit 63% 8 9 10 11 1 3 Vc c 12 r es NC CS Ref O TP 37 U4 LM8261 C104 0.1uF close to U1 Vout Mill-Max 3104-2-00-80-00-00-08-0 6 C25 0.33uF R30 1.5k R33 10k R20 82 48 R28 910 7 C15 10nF 8 - R15 0 R22 1k 13 50 R14 22k sec. SS C6 0.1uF V cc 55 17 Quiet GND SOT-23 Q7 2N2222 Mill-Max 3231-2-00-01-00-00-08-0 C29 47nF VEE C37 0.1uF 16V 7 to 12 V 0V RTN J2e 60 close to U 4 Q1 FDMS2572 Power 56 - R12 13 R21 162 Vcc 4 N drive C7 1uF close to U1 Trim Mill-Max 3104-2-00-80-00-00-08-0 R2 10 J2d close to op amp 11 C103 10nF Vref R46 33k J2c 52 S- Sense - R16 10k 34 + Mill-Max 3104-2-00-80-00-00-08-0 T520V227M004ATE007 T520V227M004ATE007 T520V227M004ATE007 V CC D4 MMSD914 S+ Sense + C100 1nF A Power GND Vcc 39 R13 12k R47 130 C20 C41 12nF 28 CS C19 ac sw eep connections V ref 500 kHz R35 open Vref 1 4O UTM C18 B R19 1Meg 200 V Fault + 3.3 V/30 A J2b 10 Power GND 32 30 46 close to Q5/Q6 Q6 NTMFS4982NF SO-8L C2220X224K2RACTU 0.22uF / 200 V Kemet 29 R17 10k 19 1 6 O UTA A Gn d6 C24 390pF 19 1 8REF A C26 Q2 IRF6217 SO-8 R25b 10k Q4 NTMFS4982NF SO-8L P drive UVLO 1 7 FLT/ SD DL M T3 2 27 J2a T520V227M004ATE007 C101 1nF .1 T2 CT02 31 C13 0.1uF 22 NC . 3 58 Vs c la m p 4 R18 10k R39 2.2 R9 1k 14 23 R40 2.2 C40 0.1uF 100 V U1 NCP1565 QFN24 43 R25a 10k R101 2.2 close to Q3/Q4 47 S O-8L 25 26 C16 10nF Q3 NTMFS4982NF R100 2.2 49 C17 R24b 10k 21 . 7 D8 MMSD914 R10 100 Mill-Max 3104-2-00-80-00-00-08-0 35 5 1 9 4 220 uF Kemet x 4 P ayton Q5 NTMFS4982NF S O-8L R24a 10k 38 20 MSS1038-152NL L1 1.5uH J1b 0V . 2 C1210C225M1RACTU C1210C225M1RACTU C1210C225M1RACTU C1210C225M1RACTU Mill-Max 3231-2-00-01-00-00-08-0 L2 0.5uH R29a 2.2 2 Mill-Max 3104-2-00-80-00-00-08-0 close to Q5/Q6 gates R29b 2.2 DUAL SOT23 C31 1uF D9 MMSD914 Vcc 4.3 V 59 D3 MBR130TG R26 270 R11 499 D6 MBR130TG 9 R7 10k R36 270 57 C10 0.1uF C38 0.1uF C33 open C9 0.1uF 2.45 V D1 1N751 C99 1nF 1 2 U5 LM4041DIM3-1.2 SOT-23 R27 10 C5 NC Quiet GND D11 Red LED U3 TL431QDBVR SOT-23 C32 C28 C11 C8 1.5nF 10nF 330pF 0.1uF Lit when fault 45 Fault Vref 41 54 R34 499 U2 PS2801 C27 2.2nF C4532X7R3D222K 2000 V - TDK Dc input voltage 36 – 72 V 2 Christophe Basso – March 2014 36-75 V 3.3 V/20 A dc-dc conv erter f or telecom applications. 1/4th brick NC - non connected ON Semiconductor Christophe Basso - February 17th 2014. Rev 1c. PCB rev 1 3.3 V/20 A Output voltage Board Picture Sense + 36 to 72 V Trim Sense - Jumper must be removed Lit when fault Input voltage from 36 V to 72 V dc. Nominal input is 48 V 3 Christophe Basso – March 2014 Output voltage is 3.3 V nominal current is 20 A Needed Equipment The needed equipments are the following:  a dc voltage source, delivering up to 80 V dc and up to 3 A  a dc load absorbing up to 100 W, Vin,max < 20 V, Iout,max < 40 A  either the above load can display dc V and dc A or separated V and A-meters are necessary  An oscilloscope with single shot capability  Kelvin sensing is necessary to connect the load to the board. If no precautions are taken, it is likely that the voltage drop at the load cables ends induces a reading error 4 Christophe Basso – March 2014 Basic Test Setup source load Jumper is removed + - Socket in which the dc-dc is firmly plugged 5 Christophe Basso – March 2014 Kelvin sense Test n°1 Source = 36 V Load = 20 A + - • Start the power supply while the load current is 20 A • Monitor the output voltage on a scope • Verify the voltage is monotonically rising 6 Christophe Basso – March 2014 Test n°1 vout  t  vout  t  Ok Bad • It is important to verify the absence of double slope • Repeat the test for Vin = 48 V and 72 V • Change load to 0 A, repeat tests. Wait 10 s between re-starts. 7 Christophe Basso – March 2014 Test n°2 source load Press short Jumper is removed + - • Press short circuit at Vin = 36 V. Led blinks, board ticks. • Repeat test for Vin = 48 V and 72 V • Release short and make sure output resumes at 3.3 V. 8 Christophe Basso – March 2014 Test n°3 source load + Probe here • Program load to dynamic current mode • Iout from 20 A to 15 A, slope 1 A/µs No pigtail! • 1 ms interval, observe Vout on scope in ac, 20 mV/div 9 Christophe Basso – March 2014 Test n°3 vout  t  vout  t  40 mV Vin = 36 V Iout = 15 to 20 A, 1 A/µs 20 mV Vin = 48 V Iout = 15 to 20 A, 1 A/µs • Run the test from Vin = 36 V (worst case) to Vin = 72 V. • Spec is to have an under/over shoot less than 60 mV 10 Christophe Basso – March 2014 Test n°4 source load + - • Leave the board for 5 mn at Vin = 36 V/20 A. • Check no thermal disjonction occurs. • Board is declared sound. 11 Christophe Basso – March 2014