DCM3623T75H31C2T00

DCM™ DC-DC Converter DCM3623x75H31C2yzz S ® US C C NRTL US Isolated, Regulated DC Converter Features & Benefits Product Ratings • Isolated, regulated DC-DC converter • Up to 320 W, 11.43 A continuous • 92.4% peak efficiency VIN = 36 V to 75 V POUT = 320 W VOUT = 28.0 V (16.8 V to 30.8 V Trim) IOUT = 11.43 A • 818 W/in3 Power density Product Description • Wide input range 36 – 75 Vdc • Safety Extra Low Voltage (SELV) 28.0 V Nominal Output The DCM Isolated, Regulated DC Converter is a DC-DC converter, operating from an unregulated, wide range input to generate an isolated 28.0 Vdc output. With its high frequency zero voltage switching (ZVS) topology, the DCM converter consistently delivers high efficiency across the input line range. Modular DCM converters and downstream DC-DC products support efficient power distribution, providing superior power system performance and connectivity from a variety of unregulated power sources to the point-of-load. • 2250 Vdc isolation • ZVS high frequency switching n Enables low-profile, high-density filtering • Optimized for array operation n Up to 8 units – 2560 W n No power derating needed n Sharing strategy permits dissimilar line voltages Leveraging the thermal and density benefits of Vicor’s ChiP packaging technology, the DCM module offers flexible thermal management options with very low top and bottom side thermal impedances. Thermally-adept ChiP based power components enable customers to achieve cost effective power system solutions with previously unattainable system size, weight and efficiency attributes, quickly and predictably. across an array • Fully operational current limit • OV, OC, UV, short circuit and thermal protection • 3623 through-hole ChiP package n 1.524” x 0.898” x 0.284” (38.72 mm x 22.8 mm x 7.21 mm) Typical Applications • • • • Industrial Process Control Heavy Equipment Defense / Aerospace Part Ordering Information Product Function Package Size Package Type Max Input Voltage Range Ratio Max Output Voltage Max Output Power Temperature Grade Option 75 H 31 C2 y zz T = -40°C – 125°C 00 = Analog Control Interface Version DCM 36 23 x DCM = DC-DC Converter Length in mm x 10 Width in mm x 10 T= Through hole ChiPs Internal Reference DCM™ DC-DC Converter Rev 1.2 Page 1 of 25 08/2017 M = -55°C – 125°C DCM3623x75H31C2yzz Typical Application DCM1 TR EN FT R1_1 L2_1 F 1_1 L1_1 Vin +IN +OUT CLOAD COUT-EXT-1 C1_1 -IN Load -OUT DCM2 TR EN FT R1_2 L2_2 F 1_2 L1_2 +IN +OUT -IN -OUT COUT-EXT-2 C1_2 ≈≈ ≈≈ DCM4 TR EN FT R1_4 L2_4 F 1_4 L1_4 +IN +OUT -IN -OUT COUT-EXT-4 C1_4 Typical Application 1: DCM3623x75H31C2yzz in an array of four units DCM TR EN L2 F1 Vin Load 1 FT R1 L1 +IN +OUT -IN -OUT C1 COUT-EXT Non-isolated Point-of-Load Regulator Load 2 Typical Application 2: Single DCM3623x75H31C2yzz, to a non-isolated regulator, and direct to load DCM™ DC-DC Converter Rev 1.2 Page 2 of 25 08/2017 DCM3623x75H31C2yzz Typical Application DCM1 TR EN FT R1_1 L2_1 F 1_1 L1_1 Vin +IN +OUT COUT-EXT-1 C1_1 -IN CLOAD -OUT Load DCM2 TR EN FT R1_2 L2_2 F 1_2 L1_2 +IN +OUT -IN -OUT COUT-EXT-2 C1_2 ≈≈ ≈≈ DCM8 TR EN FT R1_8 L2_8 F 1_8 L1_8 +IN +OUT COUT-EXT-8 C1_8 -IN -OUT Typical Application 3: Parallel operation of DCMs with common mode chokes installed on the input side to suppress common mode noise DCM™ DC-DC Converter Rev 1.2 Page 3 of 25 08/2017 DCM3623x75H31C2yzz Pin Configuration TOP VIEW 1 2 +IN A A’ +OUT TR B B’ -OUT EN C C’ +OUT FT D -IN E D’ -OUT 3623 ChiP Package Pin Descriptions Pin Number Signal Name Type A1 +IN INPUT POWER B1 TR INPUT Enables and disables trim functionality. Adjusts output voltage when trim active. C1 EN INPUT Enables and disables power supply D1 FT OUTPUT E1 -IN INPUT POWER RETURN Negative input power terminal A’2, C’2 +OUT OUTPUT POWER Positive output power terminal B’2, D’2 -OUT OUTPUT POWER RETURN Negative output power terminal Function Positive input power terminal Fault monitoring DCM™ DC-DC Converter Rev 1.2 Page 4 of 25 08/2017 DCM3623x75H31C2yzz Absolute Maximum Ratings The absolute maximum ratings below are stress ratings only. Operation at or beyond these maximum ratings can cause permanent damage to the device. Electrical specifications do not apply when operating beyond rated operating conditions. Parameter Comments Input Voltage (+IN to –IN) Input Voltage Slew Rate Min Max Unit -0.5 90.0 V -1 1 V/µs TR to - IN -0.3 3.5 V EN to -IN -0.3 3.5 V -0.3 3.5 V 5 mA 36.4 V FT to -IN Output Voltage (+Out to –Out) Dielectric withstand (input to output) -0.5 Basic insulation 2250 Vdc T Grade -40 125 °C M Grade -55 125 °C T Grade -40 125 °C M Grade -65 125 °C 18.5 A Internal Operating Temperature Storage Temperature Average Output Current Figure 1 — Thermal Specified Operating Area: Max Output Power Figure 2 — Electrical Specified Operating Area vs. Case Temp, Single unit at minimum full load efficiency DCM™ DC-DC Converter Rev 1.2 Page 5 of 25 08/2017 DCM3623x75H31C2yzz Electrical Specifications Specifications apply over all line, trim and load conditions, internal temperature TINT = 25ºC, unless otherwise noted. Boldface specifications apply over the temperature range of -40°C < TINT < 125°C for T grade and -55°C < TINT < 125°C for M grade. Attribute Symbol Conditions / Notes Min Typ Max Unit 36 48 75 V Power Input Specification Input voltage range Inrush current (peak) VIN Continuous operation IINRP With maximum COUT-EXT, full resistive load 11.0 A Input capacitance (internal) CIN-INT Effective value at nominal input voltage 17.6 µF Input capacitance (internal) ESR RCIN-INT At 1 MHz 0.40 mΩ Input inductance (external) LIN Differential mode, with no further line bypassing 1 µH 0.5 W 0.8 W 4.7 W 5.0 W No Load Specification Nominal line, see Fig. 3 Input power – disabled PQ 0.5 Worst case line, see Fig. 3 Nominal line, see Fig. 4 Input power – enabled with no load PNL 1.7 Worst case line, see Fig. 4 Power Output Specification Output voltage set point VOUT-NOM VIN = 48 V, nominal trim, at 100% Load, TINT = 25°C 27.86 28.0 28.14 V Rated output voltage trim range VOUT-TRIMMING Trim range over temp, with > 10% rated load. Specifies the Low, Nominal and High Trim conditions. 16.8 28.0 30.8 V Output voltage load regulation ΔVOUT-LOAD 1.4736 1.6296 V 4.42 V Output voltage light load regulation Output voltage temperature coefficient VOUT accuracy ΔVOUT-LL ΔVOUT-TEMP Linear load line. Output voltage increase from full rated load current to no load (Does not include light load 1.3194 regulation). See Fig. 6 and Sec. Design Guidelines 0% to 10% load, additional VOUT relative to calculated load-line point; see Fig. 6 and Sec. Design Guidelines Nominal, linear temperature coefficient, relative to TINT = 25ºC. See Fig. 5 and Design Guidelines Section The total output voltage setpoint accuracy from the %VOUT-ACCURACY calculated ideal VOUT based on load, temp and trim. Excludes ΔVOUT-LL Continuous, VOUT ≥ 28.0 V Rated output power POUT Rated output current IOUT Output current limit IOUT-LM Of rated IOUT max. Fully operational current limit, for nominal trim and below Current limit delay tIOUT-LIM The module will power limit in a fast transient event Efficiency η Continuous, VOUT ≤ 28.0 V 11.43 A 100 120 140 % 1 ms 92.4 % 89.0 % Output capacitance (internal) ESR RCOUT-INT At 1 MHz COUT-EXT- W 50% load, over rated line, temperature and trim Effective value at nominal output voltage TRANS-TRIM 320 % COUT-INT Output capacitance (external) % 90.4 Output capacitance (internal) COUT-EXT-TRANS 2.0 Full load, over line and temperature, nominal trim VOUT-PP Output capacitance (external) -2.0 mV/°C 91.5 Output voltage ripple COUT-EXT -3.73 Full load, nominal line, nominal trim 20 MHz bandwidth. At nominal trim, minimum COUT-EXT and at least 10 % rated load Output capacitance (external) -0.00 Excludes component temperature coefficient For load transients that remain > 10% rated load Excludes component temperature coefficient For load transients down to 0% rated load, with static trim Excludes component temperature coefficient For load transients down to 0% rated load, with dynamic trimming DCM™ DC-DC Converter Rev 1.2 Page 6 of 25 08/2017 367 mV 32 µF 0.069 mΩ 250 2500 µF 820 2500 µF 2000 2500 µF DCM3623x75H31C2yzz Electrical Specifications (cont.) Specifications apply over all line, trim and load conditions, internal temperature TINT = 25ºC, unless otherwise noted. Boldface specifications apply over the temperature range of -40°C < TINT < 125°C for T grade and -55°C < TINT < 125°C for M grade. Attribute Symbol Conditions / Notes Min Typ Max Unit Power Output Specifications (Cont.) Output capacitance, ESR (ext.) Initialization delay RCOUT-EXT At 10 kHz, excludes component tolerances 10 mΩ tINIT See state diagram 25 Output turn-on delay tON From rising edge EN, with VIN pre-applied. See timing diagram 200 Output turn-off delay tOFF From falling edge EN. See timing diagram tSS At full rated resistive load. Typ spec is 1-up with min COUT-EXT. Max spec is for arrays with max COUT-EXT Soft start ramp time VOUT threshold for max rated load current IOUT at startup Monotonic soft-start threshold voltage Minimum required disabled duration Minimum required disabled duration for predictable restart Voltage deviation (transient) Settling time VOUT-FL-THRESH IOUT-START VOUT-MONOTONIC 30 During startup, VOUT must achieve this threshold before output can support full rated current Max load current at startup while VOUT is below VOUT-FL_THRESH Output voltage rise becomes monotonic with 10% of preload once it crosses VOUT-MONOTONIC 40 ms µs 600 µs 120 ms 14.0 V 2.66 A 14.0 V tOFF-MIN This refers to the minimum time a module needs to be in the disabled state before it will attempt to start via EN 2 ms tOFF-MONOTONIC This refers to the minimum time a module needs to be in the disabled state before it is guaranteed to exhibit monotonic soft-start and have predictable startup timing 100 ms %VOUT-TRANS tSETTLE Minimum COUT_EXT (10 ↔ 90% load step), excluding load line. VIN-INIT INITIALIZATION SEQUENCE EN = False tMIN-OFF delay NON LATCHED FAULT tOFF ult Fa oved m Re Powertrain: Stopped FT = True tINIT delay Powertrain: Stopped FT = True Powertrain: Stopped FT = True EN = True and No Faults tON delay EN = False tOFF delay In p In ut O pu V tU L VL O o O r VIN > VIN-UVLO+ and not Over-temp TR mode latched STANDBY or O L V LO t O UV u t p In npu I EN = False tOFF-MIN delay SOFT START VOUT Ramp Up tss delay Powertrain: Active FT = False RUNNING tSS Expiry Ou Regulates VOUT Powertrain: Active FT = False tpu or mp r-te P Ove put UV Out REINITIALIZATION SEQUENCE tINIT delay Powertrain: Stopped FT = True Fault Removed Ov e Ou r-tem tpu p t U or VP VP tO pu ut O tO VP NON LATCHED FAULT tFAULT Powertrain: Stopped FT = True LATCHED FAULT EN = False DCM™ DC-DC Converter Rev 1.2 Page 9 of 25 08/2017 Powertrain: Stopped FT = True Output Input DCM™ DC-DC Converter Rev 1.2 Page 10 of 25 08/2017 FT ILOAD FULL LOAD IOUT VOUT VOUT-UVP FULL LOAD VOUT-NOM TR VTR-DIS EN VIN VIN-UVLO+/VIN-INIT VIN-OVLO+/- tINIT tON 1 Input Power On - Trim Inactive tSS 2 3 Ramp to TR Full Load Ignored tOFF tMIN_OFF 4 EN Low tSS tON 5 EN High tOFF 6 Input OVLO tSS tOFF 7 Input UVLO tSS tOFF 8 Input returned to zero DCM3623x75H31C2yzz Timing Diagrams Module Inputs are shown in blue; Module Outputs are shown in brown. Output Input DCM™ DC-DC Converter Rev 1.2 Page 11 of 25 08/2017 FT ILOAD FULL LOAD IOUT VOUT VOUT-UVP VOUT-NOM FULL LOAD TR VTR = nom VTR-EN EN VIN VIN-UVLO+/VIN-INIT VIN-OVLO+/- tINIT tON 9 Input Power On - Trim Active tSS VOUT-OVP 10 Vout based on VTR tOFF 11 Load dump and reverse current tINIT tON tSS 12 Vout OVP (primary sensed) 13 Latched fault cleared RLOAD tIOUT-LIM 14 Current Limit with Resistive Load tFAULT 15 Resistive Load with decresing R tINIT 16 Overload induced Output UVP tON tSS DCM3623x75H31C2yzz Timing Diagrams (Cont.) Module Inputs are shown in blue; Module Outputs are shown in brown. DCM3623x75H31C2yzz Typical Performance Characteristics





















 
 



   The following figures present typical performance at TC = 25ºC, unless otherwise noted. See associated figures for general trend data.  
 
 
 
 



 
 
    
   
   Figure 3 — Disabled power dissipation vs. VIN         Figure 6 — Ideal VOUT vs. load current, at 25°C case 
 
   








         
    

 Figure 4 — No load power dissipation vs. VIN, at nominal trim        




        Figure 7 — 100% to 10% load transient response, VIN = 48 V, nominal trim, COUT_EXT = 250 µF
               Figure 5 — Ideal VOUT vs. case temperature, at full load Figure 8 — 10% to 100% load transient response, VIN = 48 V, nominal trim, COUT_EXT = 250 µF DCM™ DC-DC Converter Rev 1.2 Page 12 of 25 08/2017 DCM3623x75H31C2yzz Typical Performance Characteristics (cont.)     

    
   

  
       
       

 
 

 
 


     
    

  


  
 






     
       
         
  
 

 
  
  
  
 
 

 
 
    
  Figure 13 — Efficiency and power dissipation vs.load at TCASE = 25°C, nominal trim
     Figure 10 — Full Load Efficiency vs. VIN, at nominal trim
  
    
  
  
 
 
 
 
  
 
 
 
Figure 12 — Efficiency and power dissipation vs.load at TCASE = -40°C, nominal trim
       Figure 9 — Full Load Efficiency vs. VIN, at low trim

     
  Figure 11 — Full Load Efficiency vs. VIN, at high trim 
 
 
  
  
 Figure 14 — Efficiency and power dissipation vs.load at TCASE = 90°C, nominal trim DCM™ DC-DC Converter Rev 1.2 Page 13 of 25 08/2017
   
   
      
  The following figures present typical performance at TC = 25ºC, unless otherwise noted. See associated figures for general trend data. DCM3623x75H31C2yzz Typical Performance Characteristics (cont.)








   
    The following figures present typical performance at TC = 25ºC, unless otherwise noted. See associated figures for general trend data. 



































  
  




  
     Figure 18 — Nominal powertrain switching frequency vs. load, Figure 15 — Nominal powertrain switching frequency vs. load, at nominal VIN at nominal trim Figure 16 — Effective internal input capacitance vs. applied voltage Figure 19 — Output voltage ripple, VIN = 48 V, Figure 17 —Startup from EN, VIN = 48 V, COUT_EXT = 2500 µF, RLOAD = 2.450 Ω DCM™ DC-DC Converter Rev 1.2 Page 14 of 25 08/2017 VOUT = 28.0 V, COUT_EXT = 250 µF, RLOAD = 2.450 Ω DCM3623x75H31C2yzz General Characteristics Specifications apply over all line, trim and load conditions, internal temperature TINT = 25ºC, unless otherwise noted. Boldface specifications apply over the temperature range of -40°C < TINT < 125°C for T grade and -55°C < TINT < 125°C for M grade. Attribute Symbol Conditions / Notes Min Typ Max Unit Mechanical Length L 38.34/[1.509] 38.72/[1.524] 39.10/[1.539] mm/[in] Width W 22.67/[0.893] 22.8/[0.898] 22.93/[0.903] mm/[in] Height H 7.11/[0.28] 7.21/[0.284] 7.31/[0.288] mm/[in] Volume Vol Weight W Lead finish No heat sink 6.41/[0.39] cm3/[in3] 24.0/[0.85] g/[oz] Nickel 0.51 2.03 Palladium 0.02 0.15 Gold 0.003 0.051 T-Grade -40 125 °C M-Grade -55 125 °C µm Thermal Operating internal temperature Thermal resistance top side Thermal resistance leads Thermal resistance bottom side TINT θINT-TOP θINT-LEADS θINT-BOTTOM Estimated thermal resistance to maximum temperature internal component from 2.01 °C/W 4.50 °C/W 2.27 °C/W 17.7 Ws/°C isothermal top Estimated thermal resistance to maximum temperature internal component from isothermal leads Estimated thermal resistance to maximum temperature internal component from isothermal bottom Thermal capacity Assembly Storage temperature TST HBM ESD rating CDM T-Grade -40 125 °C M-Grade -65 125 °C Method per Human Body Model Test ESDA/JEDEC JDS-001-2012 Charged Device Model JESD22-C101E CLASS 1C V CLASS 2 Soldering [1] Peak temperature top case [1] For further information, please contact factory applications Product is not intended for reflow solder attach. DCM™ DC-DC Converter Rev 1.2 Page 15 of 25 08/2017 135 °C DCM3623x75H31C2yzz General Characteristics (Cont.) Specifications apply over all line, trim and load conditions, internal temperature TINT = 25ºC, unless otherwise noted. Boldface specifications apply over the temperature range of -40°C < TINT < 125°C for T grade and -55°C < TINT < 125°C for M grade. Attribute Symbol Conditions / Notes Min Typ Max Unit Safety Dielectric Withstand Test VHIPOT IN to OUT 2250 Vdc IN to CASE 2250 Vdc OUT to CASE 707 Vdc Reliability MIL-HDBK-217 FN2 Parts Count 25°C Ground Benign, Stationary, Indoors / MTBF 3.39 MHrs 5.68 MHrs Computer Telcordia Issue 2, Method I Case 3, 25°C, 100% D.C., GB, GC Agency Approvals cTÜVus, EN 60950-1 Agency approvals/standards cURus, UL 60950-1 CE Marked for Low Voltage Directive and RoHS Recast Directive, as applicable Previous Part Number DCM48AP280x320A50 DCM™ DC-DC Converter Rev 1.2 Page 16 of 25 08/2017 DCM3623x75H31C2yzz Pin Functions The DCM will latch trim behavior at application of VIN (once VIN exceeds VIN-UVLO+), and persist in that same behavior until loss of input voltage. n At application of VIN, if TR is sampled at above VTRIM-DIS, the module will latch in a non-trim mode, and will ignore the TR input for as long as VIN is present. +IN, -IN Input power pins. -IN is the reference for all control pins, and therefore a Kelvin connection for the control signals is recommended as close as possible to the pin on the package, to reduce effects of voltage drop due to -IN currents. n At application of VIN, if TR is sampled at below VTRIM-EN, the TR will serve as an input to control the real time output voltage, relative to full load, 25°C. It will persist in this behavior until VIN is no longer present. +OUT, -OUT Output power pins. If trim is active when the DCM is operating, the TR pin provides dynamic trim control at a typical 30 Hz of -3dB bandwidth over the output voltage. TR also decreases the current limit threshold when trimming above VOUT-NOM. EN (Enable) This pin enables and disables the DCM converter; when held low the unit will be disabled. It is referenced to the -IN pin of the converter. The EN pin has an internal pull-up to VCC through a 10 kΩ resistor. FT (Fault) n Output enable: When EN is allowed to pull up above the enable The FT pin provides a Fault signal. threshold, the module will be enabled. If leaving EN floating, it is pulled up to VCC and the module will be enabled. Anytime the module is enabled and has not recognized a fault, the FT pin is inactive. FT has an internal 499 kΩ pull-up to Vcc, therefore a shunt resistor, RSHUNT, of approximately 50 kΩ can be used to ensure the LED is completly off when there is no fault, per the diagram below. n Output disable: EN may be pulled down externally in order to disable the module. n EN is an input only, it does not pull low in the event of a fault. n The EN pins of multiple units should be driven high concurrently Whenever the powertrain stops (due to a fault protection or disabling the module by pulling EN low), the FT pin becomes active and provides current to drive an external circuit. to permit the array to start in to maximum rated load. However, the direct interconnection of multiple EN pins requires additional considerations, as discussed in the section on Array Operation. When active, FT pin drives to VCC, with up to 4 mA of external loading. Module may be damaged from an over-current FT drive, thus a resistor in series for current limiting is recommended. TR (Trim) The TR pin is used to select the trim mode and to trim the output voltage of the DCM converter. The TR pin has an internal pull-up to VCC through a 10.0 kΩ resistor. The FT pin becomes active momentarily when the module starts up. Typical External Circuits for Signal Pins (TR, EN, FT) Vcc Vcc 10k Vcc Output Voltage Reference, Current Limit Reference and Soft Start Control TR 499k Fault Monitoring 10k Soft Start and Fault Monitoring FT EN RSERIES SW RTRIM RSHUNT Kelvin -IN connection DCM™ DC-DC Converter Rev 1.2 Page 17 of 25 08/2017 DCM3623x75H31C2yzz Design Guidelines Nominal Output Voltage Temperature Coefficient A second additive term to the programmed output voltage is based on the temperature of the module. This term permits improved thermal balancing among modules in an array, especially when the factory nominal trim point is utilized (trim mode inactive). This term is much smaller than the load line described above, representing only a -3.73 mV/°C change. Regulation coefficient is relative to 25°C. Building Blocks and System Design The DCM™ converter input accepts the full 36 to 75 V range, and it generates an isolated trimmable 28.0 Vdc output. Multiple DCMs may be paralleled for higher power capacity via wireless load sharing, even when they are operating off of different input voltage supplies. For nominal trim and full load, the output voltage relates to the temperature according to the following equation: The DCM converter provides a regulated output voltage around defined nominal load line and temperature coefficients. The load line and temperature coefficients enable configuration of an array of DCM converters which manage the output load with no share bus among modules. Downstream regulators may be used to provide tighter voltage regulation, if required. VOUT-FL = 28.0 -3.730 • 0.001 • (TINT - 25) where TINT is in °C. The DCM3623x75H31C2yzz may be used in standalone applications where the output power requirements are up to 320 W. However, it is easily deployed as arrays of modules to increase power handling capacity. Arrays of up to eight units have been qualified for 2560 W capacity. Application of DCM converters in an array requires no derating of the maximum available power versus what is specified for a single module. The impact of temperature coefficient on the output voltage is absolute, and does not scale with trim or load. Trim Mode and Output Trim Control When the input voltage is initially applied to a DCM, and after tINIT elapses, the trim pin voltage VTR is sampled. The TR pin has an internal pull up resistor to VCC, so unless external circuitry pulls the pin voltage lower, it will pull up to VCC. If the initially sampled trim pin voltage is higher than VTRIM-DIS, then the DCM will disable trimming as long as the VIN remains applied. In this case, for all subsequent operation the output voltage will be programmed to the nominal. This minimizes the support components required for applications that only require the nominal rated Vout, and also provides the best output setpoint accuracy, as there are no additional errors from external trim components Note: For more information on operation of single DCM, refer to “Single DCM as an Isolated, Regulated DC-DC Converter” application note AN:029. Soft Start When the DCM starts, it will go through a soft start. The soft start routine ramps the output voltage by modulating the internal error amplifier reference. This causes the output voltage to approximate a piecewise linear ramp. The output ramp finishes when the voltage reaches either the nominal output voltage, or the trimmed output voltage in cases where trim mode is active. If at initial application of VIN, the TR pin voltage is prevented from exceeding VTRIM-EN, then the DCM will activate trim mode, and it will remain active for as long as VIN is applied. During soft-start, the maximum load current capability is reduced. Until Vout achieves at least VOUT-FL-THRESH, the output current must be less than IOUT-START in order to guarantee startup. Note that this is current available to the load, above that which is required to charge the output capacitor. VOUT set point under full load and room temperature can be calculated using the equation below: VOUT-FL @ 25°C = 11.64 + (21.910 • VTR/VCC) (3) Note that the trim mode is not changed when a DCM recovers from any fault condition or being disabled. Nominal Output Voltage Load Line Throughout this document, the programmed output voltage, (either the specified nominal output voltage if trim is inactive or the trimmed output voltage if trim is active), is specified at full load, and at room temperature. The actual output voltage of the DCM is given by the programmed trimmed output voltage, with modification based on load and temperature. The nominal output voltage is 28.0 V, and the actual output voltage will match this at full load and room temperature with trim inactive. Module performance is guaranteed through output voltage trim range VOUT-TRIMMING. If VOUT is trimmed above this range, then certain combinations of line and load transient conditions may trigger the output OVP. Overall Output Voltage Transfer Function Taking load line (equation 1), temperature coefficient (equation 2) and trim (equation 3) into account, the general equation relating the DC VOUT to programmed trim (when active), load, and temperature is given by: The largest modification to the actual output voltage compared to the programmed output is due to the 5.263% VOUT-NOM load line, which for this model corresponds to ΔVOUT-LOAD of 1.4736V. As the load is reduced, the internal error amplifier reference, and by extension the output voltage, rises in response. This load line is the primary enabler of the wireless current sharing amongst an array of DCMs. VOUT = 11.64 + (21.910 • VTR/VCC) + 1.4736 • (1 - IOUT / 11.43) -3.730 • 0.001 • (TINT -25) + ∆VOUT-LL (4) Finally, note that when the load current is below 10% of the rated capacity, there is an additional ∆V which may add to the output voltage, depending on the line voltage which is related to light load boosting. Please see the section on light load boosting below for details. The load line impact on the output voltage is absolute, and does not scale with programmed trim voltage. For a given programmed output voltage, the actual output voltage versus load current at for nominal trim and room temperature is given by the following equation: VOUT @ 25° = 28.0 + 1.4736 • (1 - IOUT / 11.43) (2) Use 0 V for ∆VOUT-LL when load is above 10% of rated load. See section on light load boosting operation for light load effects on output voltage. (1) DCM™ DC-DC Converter Rev 1.2 Page 18 of 25 08/2017 DCM3623x75H31C2yzz n Maximum voltage rating (usually greater than the maximum Output Current Limit The DCM features a fully operational current limit which effectively keeps the module operating inside the Safe Operating Area (SOA) for all valid trim and load profiles. The current limit approximates a “brick wall” limit, where the output current is prevented from exceeding the current limit threshold by reducing the output voltage via the internal error amplifier reference. The current limit threshold at nominal trim and below is typically 120% of rated output current, but it can vary between 100% to 140%. In order to preserve the SOA, when the converter is trimmed above the nominal output voltage, the current limit threshold is automatically reduced to limit the available output power. possible input voltage) n Ambient temperature n Breaking capacity per application requirements n Nominal melting I2t n Recommended fuse: See Agency Approvals for Recommended Fuse http://www.vicorpower.com/dc-dc/isolatedregulated/dcm#Documentation Fault Handling Input Undervoltage Fault Protection (UVLO) The converter’s input voltage is monitored to detect an input under voltage condition. If the converter is not already running, then it will ignore enable commands until the input voltage is greater than VIN-UVLO+. If the converter is running and the input voltage falls below VIN-UVLO-, the converter recognizes a fault condition, the powertrain stops switching, and the output voltage of the unit falls. When the output current exceeds the current limit threshold, current limit action is held off by 1ms, which permits the DCM to momentarily deliver higher peak output currents to the load. Peak output power during this time is still constrained by the internal Power Limit of the module. The fast Power Limit and relatively slow Current Limit work together to keep the module inside the SOA. Delaying entry into current limit also permits the DCM to minimize droop voltage for load steps. Input voltage transients which fall below UVLO for less than tUVLO may not be detected by the fault proection logic, in which case the converter will continue regular operation. No protection is required in this case. Sustained operation in current limit is permitted, and no derating of output power is required, even in an array configuration. Some applications may benefit from well matched current distribution, in which case fine tuning sharing via the trim pins permits control over sharing. The DCM does not require this for proper operation, due to the power limit and current limit behaviors described here. Once the UVLO fault is detected by the fault protection logic, the converter shuts down and waits for the input voltage to rise above VIN-UVLO+. Provided the converter is still enabled, it will then restart. Input Overvoltage Fault Protection (OVLO) The converter’s input voltage is monitored to detect an input over voltage condition. When the input voltage is more than the VIN-OVLO+, a fault is detected, the powertrain stops switching, and the output voltage of the converter falls. Current limit can reduce the output voltage to as little as the UVP threshold (VOUT-UVP). Below this minimum output voltage compliance level, further loading will cause the module to shut down due to the output undervoltage fault protection. After an OVLO fault occurs, the converter will wait for the input voltage to fall below VIN-OVLO-. Provided the converter is still enabled, the powertrain will restart. Line Impedance, Input Slew rate and Input Stability Requirements Connect a high-quality, low-noise power supply to the +IN and –IN terminals. Additional capacitance may have to be added between +IN and –IN to make up for impedances in the interconnect cables as well as deficiencies in the source. The powertrain controller itself also monitors the input voltage. Transient OVLO events which have not yet been detected by the fault sequence logic may first be detected by the controller if the input slew rate is sufficiently large. In this case, powertrain switching will immediately stop. If the input voltage falls back in range before the fault sequence logic detects the out of range condition, the powertrain will resume switching and the fault logic will not interrupt operation Regardless of whether the powertrain is running at the time or not, if the input voltage does not recover from OVLO before tOVLO, the converter fault logic will detect the fault. Excessive source impedance can bring about system stability issues for a regulated DC-DC converter, and must either be avoided or compensated by filtering components. A 1000 µF input capacitor is the minimum recommended in case the source impedance is insufficient to satisfy stability requirements. Additional information can be found in the filter design application note: www.vicorpower.com/documents/application_notes/vichip_appnote23.pdf Output Undervoltage Fault Protection (UVP) The converter determines that an output overload or short circuit condition exists by measuring its primary sensed output voltage and the output of the internal error amplifier. In general, whenever the powertrain is switching and the primary-sensed output voltage falls below VOUT-UVP threshold, a short circuit fault will be registered. Once an output undervoltage condition is detected, the powertrain immediately stops switching, and the output voltage of the converter falls. The converter remains disabled for a time tFAULT. Once recovered and provided the converter is still enabled, the powertrain will again enter the soft start sequence after tINIT and tON. Please refer to this input filter design tool to ensure input stability: http://app2.vicorpower.com/filterDesign/intiFilter.do. Ensure that the input voltage slew rate is less than 1V/us, otherwise a pre-charge circuit is required for the DCM input to control the input voltage slew rate and prevent overstress to input stage components. Input Fuse Selection The DCM is not internally fused in order to provide flexibility in configuring power systems. Input line fusing is recommended at the system level, in order to provide thermal protection in case of catastrophic failure. The fuse shall be selected by closely matching system requirements with the following characteristics: Temperature Fault Protections (OTP) The fault logic monitors the internal temperature of the converter. If the measured temperature exceeds TINT-OTP, a temperature fault is registered. As with the under voltage fault protection, once a n Current rating (usually greater than the DCM converter’s maximum current) DCM™ DC-DC Converter Rev 1.2 Page 19 of 25 08/2017 DCM3623x75H31C2yzz The ChiP package provides a high degree of flexibility in that it presents three pathways to remove heat from internal power dissipating components. Heat may be removed from the top surface, the bottom surface and the leads. The extent to which these three surfaces are cooled is a key component for determining the maximum power that is available from a ChiP, as can be seen from Figure 20. temperature fault is registered, the powertrain immediately stops switching, the output voltage of the converter falls, and the converter remains disabled for at least time tFAULT. Then, the converter waits for the internal temperature to return to below TINT-OTP before recovering. Provided the converter is still enabled, the DCM will restart after tINIT and tON. Output Overvoltage Fault Protection (OVP) The converter monitors the output voltage during each switching cycle by a corresponding voltage reflected to the primary side control circuitry. If the primary sensed output voltage exceeds VOUT-OVP, the OVP fault protection is triggered. The control logic disables the powertrain, and the output voltage of the converter falls. Since the ChiP has a maximum internal temperature rating, it is necessary to estimate this internal temperature based on a real thermal solution. Given that there are three pathways to remove heat from the ChiP, it is helpful to simplify the thermal solution into a roughly equivalent circuit where power dissipation is modeled as a current source, isothermal surface temperatures are represented as voltage sources and the thermal resistances are represented as resistors. Figure 20 shows the "thermal circuit" for a 3623 ChiP DCM, in an application where both case top and case bottom, and leads are cooled. In this case, the DCM power dissipation is PDTOTAL and the three surface temperatures are represented as TCASE_TOP, TCASE_BOTTOM, and TLEADS. This thermal system can now be very easily analyzed with simple resistors, voltage sources, and a current source. This type of fault is latched, and the converter will not start again until the latch is cleared. Clearing the fault latch is achieved by either disabling the converter via the EN pin, or else by removing the input power such that the input voltage falls below VIN-INIT. External Output Capacitance The DCM converter internal compensation requires a minimum external output capacitor. An external capacitor in the range of 250 to 2500 µF with ESR of 10 mΩ is required, per DCM for control loop compensation purposes. This analysis provides an estimate of heat flow through the various pathways as well as internal temperature. However some DCM models require an increase to the minimum external output capacitor value in certain loading and trim condition. In applications where the load can go below 10% of rated load but the output trim is held constant, the range of output capacitor required is given by COUT-EXT-TRANS in the Electrical Specifications table. If the load can go below 10% of rated load and the DCM output trim is also dynamically varied, the range of output capacitor required is given by COUT-EXT-TRANS-TRIM in the Electrical Specifications table. Thermal Resistance Top MAX INTERNAL TEMP θINT-TOP°C / W Thermal Resistance Bottom Thermal Resistance Leads θINT-BOTTOM°C / W Power Dissipation (W) Light Load Boosting Under light load conditions, the DCM converter may operate in light load boosting depending on the line voltage. Light load boosting occurs whenever the internal power consumption of the converter combined with the external output load is less than the minimum power transfer per switching cycle. In order to maintain regulation, the error amplifier will switch the powertrain off and on repeatedly, to effectively lower the average switching frequency, and permit operation with no external load. During the time when the power train is off, the module internal consumption is significantly reduced, and so there is a notable reduction in no-load input power in light load boosting. When the load is less than 10% of rated Iout, the output voltage may rise by a maximum of 4.42 V, above the output voltage calculated from trim, temperature, and load line conditions. TCASE_BOTTOM(°C) θ­­INT-LEADS°C / W + – TLEADS(°C) + – TCASE_TOP(°C) + – Figure 20 — Double side cooling and leads thermal model Alternatively, equations can be written around this circuit and analyzed algebraically: TINT – PD1 • θINT-TOP = TCASE_TOP TINT – PD2 • θINT-BOTTOM = TCASE_BOTTOM TINT – PD3 • θINT-LEADS = TLEADS PDTOTAL = PD1+ PD2+ PD3 Where TINT represents the internal temperature and PD1, PD2, and PD3 represent the heat flow through the top side, bottom side, and leads respectively. Thermal Design Based on the safe thermal operating area shown in page 5, the full rated power of the DCM3623x75H31C2yzz can be processed provided that the top, bottom, and leads are all held below 93°C. These curves highlight the benefits of dual sided thermal management, but also demonstrate the flexibility of the Vicor ChiP platform for customers who are limited to cooling only the top or the bottom surface. Thermal Resistance Top θINT-TOP°C / W Thermal Resistance Bottom θINT-BOTTOM°C / W Power Dissipation (W) The OTP sensor is located on the top side of the internal PCB structure. Therefore in order to ensure effective over-temperature fault protection, the case bottom temperature must be constrained by the thermal solution such that it does not exceed the temperature of the case top. TCASE_BOTTOM(°C) MAX INTERNAL TEMP Thermal Resistance Leads θINT-LEADS°C / W TLEADS(°C) + – TCASE_TOP(°C) Figure 21 — One side cooling and leads thermal model DCM™ DC-DC Converter Rev 1.2 Page 20 of 25 08/2017 + – DCM3623x75H31C2yzz COUT-EXT-x: electrolytic or tantalum capacitor, 250 µF ≤ C3 ≤2500 µF; C4, C5: additional ceramic /electrolytic capacitors, if needed for output ripple filtering; In order to help sensitive signal circuits reject potential noise, additional components are recommended: R2_x: 301 Ohm, facilitate noise attenuation for TR pin; FB1_x, C2_x: FB1 is a ferrite bead with an impedance of at least 10 Ω at 100MHz. C2_x can be a ceramic capacitor of 0.1uF. Facilitate noise attenuation for EN pin. Figure 21 shows a scenario where there is no bottom side cooling. In this case, the heat flow path to the bottom is left open and the equations now simplify to: TINT – PD1 • θINT-TOP = TCASE_TOP TINT – PD3 • θINT-LEADS = TLEADS PDTOTAL = PD1 + PD3 Note: Use an RCR filter network as suggested in the application note AN:030 to reduce the noise on the signal pins. Thermal Resistance Top MAX INTERNAL TEMP θINT-TOP°C / W Thermal Resistance Bottom θINT-BOTTOM°C / W Power Dissipation (W) Note: In case of the excessive line inductance, a properly sized decoupling capacitor CDECOUPLE is required as shown in Figure 23 and Figure 24. Thermal Resistance Leads TCASE_BOTTOM(°C) θINT-LEADS°C / W TLEADS(°C) TCASE_TOP(°C) + – VTR VEN DCM1 R2_1 TR EN FB1_1 C2_1 R1_1 FT L2_1 F 1_1 +IN +IN L1_1 C1_1 CDECOUPLE COUT-EXT-1 -IN Figure 22 — One side cooling thermal model +OUT +OUT -IN C4 -OUT C5 -OUT DCM2 R2_2 TR EN FB1_2 C2_2 R1_2 Figure 22 shows a scenario where there is no bottom side and leads cooling. In this case, the heat flow path to the bottom is left open and the equations now simplify to: FT L2_2 F 1_2 +IN L1_2 C1_2 +OUT COUT-EXT-2 -IN ≈≈ TINT – PD1 • θINT-TOP = TCASE_TOP PDTOTAL = PD1 ≈≈ ≈ ≈≈ DCM8 R2_8 TR EN FB1_8 C2_8 R1_8 -OUT R3 FT L2_8 F 1_8 L1_8 R4 C1_8 D1 +IN +OUT COUT-EXT-8 -IN -OUT Shared -IN Kelvin Vicor provides a suite of online tools, including a simulator and thermal estimator which greatly simplify the task of determining whether or not a DCM thermal configuration is sufficient for a given condition. These tools can be found at: www.vicorpower.com/powerbench. Figure 23 — DCM paralleling configuration circuit 1 When common mode noise rejection in the input side is needed, common mode chokes can be added in the input side of each DCM. An example of DCM paralleling circuit is shown below: Array Operation A decoupling network is needed to facilitate paralleling: n An output inductor should be added to each DCM, before the outputs are bussed together to provide decoupling. DCM1 n Each DCM needs a separate input filter, even if the multiple DCMs R2_1 + VTR1 _ R1_1 share the same input voltage source. These filters limit the ripple current reflected from each DCM, and also help suppress generation of beat frequency currents that can result when multiple powertrains input stages are permitted to direclty interact. SGND1 F 1_1 +IN L1_1 CDECOUPLE + V_EN1 TR EN FB1_1 C2_1 R3_1 FT L2_1 R4_1 C1_1 D1_1 -IN +IN COUT-EXT-1 -IN SGND1 R2_2 + VTR2 _ R1_2 SGND2 F 1_2 L1_2 If signal pins (TR, EN, FT) are not used, they can be left floating, and DCM will work in the nominal output condition. + V_EN2 +OUT +OUT C4 -OUT C5 -OUT DCM2 TR EN FB1_2 C2_2 R3_2 FT L2_2 R4_2 C1_2 D1_2 +IN +OUT COUT-EXT-2 -IN -OUT SGND2 ≈≈ When common mode noise in the input side is not a concern, TR and EN can be driven and FT received using a single Kelvin connection to the shared -IN as a reference. R2_8 + VTR8 _ R1_8 L1_8 Note: For more information on parallel operation of DCMs, refer to “Parallel DCMs” application note AN:030. + V_EN8 SGND8 F 1_8 C1_8 ≈≈ DCM8 TR EN FB1_8 C2_8 R3_8 FT L2_8 R4_8 D1_8 +IN +OUT COUT-EXT-8 -IN -OUT SGND8 An example of DCM paralleling circuit is shown in Figure 23. Figure 24 — DCM paralleling configuration circuit 2 Recommended values to start with: L1_x: 1 µH, minimized DCR; R1_x: 0.3 Ω; C1_x: Ceramic capacitors in parallel, C1 = 20 µF; L2_x: L2 ≥ 0.15 µH; Notice that each group of control pins need to be individually driven and isolated from the other groups control pins. This is because -IN of each DCM can be at a different voltage due to the common mode chokes. Attempting to share control pin circuitry could lead to incorrect behavior of the DCMs. DCM™ DC-DC Converter Rev 1.2 Page 21 of 25 08/2017 DCM3623x75H31C2yzz An array of DCMs used at the full array rated power may generally have one or more DCMs operating at current limit, due to sharing errors. Load sharing is functionally managed by the load line. Thermal balancing is improved by the nominal effective temperature coefficient of the output voltage setpoint. DCMs in current limit will operate with higher output current or power than the rated levels. Therefore the following Thermal Safe Operating Area plot should be used for array use, or loads that drive the DCM in to current limit for sustained operation. Figure 25 — Thermal Specified Operating Area: Max Power Dissipation vs. Case Temp for arrays or current limited operation DCM™ DC-DC Converter Rev 1.2 Page 22 of 25 08/2017 DCM3623x75H31C2yzz DCM Module Product Outline Drawing Recommended PCB Footprint and Pinout 38.72±.38 1.524±.015 11.43 .450 19.36 .762 0 1.52 .060 (2) PL. 11.40 .449 0 0 22.80±.13 .898±.005 1.02 .040 (3) PL. 0 1.52 .060 (4) PL. TOP VIEW (COMPONENT SIDE) .05 [.002] 7.21±.10 .284±.004 SEATING . PLANE 4.17 .164 (9) PL. 18.60 .732 0 18.60 .732 .41 .016 (9) PL. 8.25 .325 8.00 .315 2.75 .108 0 0 2.75 .108 1.38 .054 4.13 .162 1.38 .054 8.00 .315 0 8.25 .325 8.00±.08 .315±.003 4.13±.08 .162±.003 1.38±.08 .054±.003 +IN 0 2.03 .080 PLATED THRU .25 [.010] ANNULAR RING (2) PL. 2.75±.08 .108±.003 -OUT TR 0 EN FT 8.00±.08 .315±.003 8.25±.08 .325±.003 +OUT -IN +OUT 2.75±.08 .108±.003 -OUT 8.25±.08 .325±.003 0 1.38±.08 .054±.003 0 18.60±.08 .732±.003 1.52 .060 PLATED THRU .25 [.010] ANNULAR RING (3) PL. 18.60±.08 .732±.003 BOTTOM VIEW RECOMMENDED HOLE PATTERN (COMPONENT SIDE) NOTES: 1- RoHS COMPLIANT PER CST-0001 LATEST REVISION. DCM™ DC-DC Converter Rev 1.2 Page 23 of 25 08/2017 2.03 .080 PLATED THRU .38 [.015] ANNULAR RING (4) PL. DCM3623x75H31C2yzz Revision History Revision Date Description 1.0 09/19/16 Release of current data sheet with new part number 1.1 05/03/17 Updated agency approvals Added 2 decimal points to the UVLO and OVLO powertrain protection specifications 1.2 08/04/17 Updated typical applications Updated height and length specifications Updated mechanical drawing DCM™ DC-DC Converter Rev 1.2 Page 24 of 25 08/2017 Page Number(s) n/a 1 & 16 7 1 15 23 DCM3623x75H31C2yzz 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 makes no representations or warranties with respect to the accuracy or completeness of the contents of this publication. Vicor reserves the right to make changes to any products, specifications, and product descriptions at any time without notice. Information published by Vicor has been checked and is believed to be accurate at the time it was printed; however, Vicor assumes no responsibility for inaccuracies. Testing and other quality controls are used to the extent Vicor deems necessary to support Vicor’s product warranty. Except where mandated by government requirements, testing of all parameters of each product is not necessarily performed. Specifications are subject to change without notice. Visit http://www.vicorpower.com/dc-dc/isolated-regulated/dcm for the latest product information. Vicor’s Standard Terms and Conditions and Product Warranty All sales are subject to Vicor’s Standard Terms and Conditions of Sale, and Product Warranty which are available on Vicor’s webpage (http://www.vicorpower.com/termsconditionswarranty) or upon request. Life Support Policy VICOR’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS WITHOUT THE EXPRESS PRIOR WRITTEN APPROVAL OF THE CHIEF EXECUTIVE OFFICER AND GENERAL COUNSEL OF VICOR CORPORATION. As used herein, life support devices or systems are devices which (a) are intended for surgical implant into the body, or (b) support or sustain life and whose failure to perform when properly used in accordance with instructions for use provided in the labeling can be reasonably expected to result in a significant injury to the user. A critical component is any component in a life support device or system whose failure to perform can be reasonably expected to cause the failure of the life support device or system or to affect its safety or effectiveness. Per Vicor Terms and Conditions of Sale, the user of Vicor products and components in life support applications assumes all risks of such use and indemnifies Vicor against all liability and damages. Intellectual Property Notice Vicor and its subsidiaries own Intellectual Property (including issued U.S. and Foreign Patents and pending patent applications) relating to the products described in this data sheet. No license, whether express, implied, or arising by estoppel or otherwise, to any intellectual property rights is granted by this document. Interested parties should contact Vicor’s Intellectual Property Department. The products described on this data sheet are protected by the following U.S. Patents Numbers: RE40,072; 7,561,446; 7,920,391; 7,782,639; 8,427,269; 6,421,262 and other patents pending. Contact Us: http://www.vicorpower.com/contact-us Vicor Corporation 25 Frontage Road Andover, MA, USA 01810 Tel: 800-735-6200 Fax: 978-475-6715 www.vicorpower.com email Customer Service: custserv@vicorpower.com Technical Support: apps@vicorpower.com ©2017 Vicor Corporation. All rights reserved. The Vicor name is a registered trademark of Vicor Corporation. All other trademarks, product names, logos and brands are property of their respective owners. DCM™ DC-DC Converter Rev 1.2 Page 25 of 25 08/2017