V048F240T012A

Not Recommended for New Designs VTM™ Current Multiplier V048x240y012A S C NRTL US High Efficiency, Sine Amplitude Converter™ FEATURES • 48 Vdc to 24 Vdc 12.5 A current multiplier - Operating from standard 48 V or 24 V PRM™ Regulators • High efficiency (>95%) reduces system power consumption • High density (41 A/in3) • “Full Chip” VI Chip® package enables surface mount, low impedance interconnect to system board • Contains built-in protection features against: - Overvoltage Lockout Overcurrent Short Circuit Overtemperature • Provides enable / disable control, internal temperature monitoring • ZVS / ZCS resonant Sine Amplitude Converter topology • Less than 50ºC temperature rise at full load in typical applications TYPICAL APPLICATIONS • High End Computing Systems • Automated Test Equipment • High Density Power Supplies • Communications Systems DESCRIPTION The VI Chip current multiplier is a high efficiency (>95%) Sine Amplitude Converter™ (SAC) operating from a 26 to 55 Vdc primary bus to deliver an isolated output. The Sine Amplitude Converter offers a low AC impedance beyond the bandwidth of most downstream regulators; therefore capacitance normally at the load can be located at the input to the Sine Amplitude Converter. Since the K factor of the V048x240y012A is 1/2, the capacitance value can be reduced by a factor of 4, resulting in savings of board area, materials and total system cost. The V048x240y012A is provided in a VI Chip package compatible with standard pick-and-place and surface mount assembly processes. The co-molded VI Chip package provides enhanced thermal management due to a large thermal interface area and superior thermal conductivity. The high conversion efficiency of the V048x240y012A increases overall system efficiency and lowers operating costs compared to conventional approaches. The V048x240y012A enables the utilization of Factorized Power Architecture™ which provides efficiency and size benefits by lowering conversion and distribution losses and promoting high density point of load conversion. VIN = 26 to 55 V IOUT = 12.5 A (NOM) VOUT = 13.0 to 27.5 V (NO LOAD) K = 1/2 PART NUMBERING PART NUMBER PACKAGE STYLE F = J-Lead V048 x 240 y 012A T = Through hole T = -40 to 125°C M = -55 to 125°C For Storage and Operating Temperatures see Section 6.0 General Characteristics TYPICAL APPLICATION Regulator Voltage Transformer VC SG OS CD PR PC TM IL PRODUCT GRADE TM VC PC ™ VTM Transformer ™ PRM Regulator +In +Out -In -Out +In +Out -In -Out VIN Factorized Power ArchitectureTM VTM™ Current Multiplier Rev 1.2 vicorpower.com Page 1 of 18 09/2015 800 927.9474 L O A D (See Application Note AN:024) Not Recommended for New Designs V048x240y012A 1.0 ABSOLUTE MAXIMUM VOLTAGE RATINGS The absolute maximum ratings below are stress ratings only. Operation at or beyond these maximum ratings can cause permanent damage to the device. MIN MAX UNIT MIN MAX UNIT + IN to - IN . . . . . . . . . . . . . . . . . . . . . . . -1.0 60 VDC VC to - IN . . . . . . . . . . . . . . . . . . . . . . . . PC to - IN . . . . . . . . . . . . . . . . . . . . . . . . -0.3 20 VDC + IN / - IN to + OUT / - OUT (hipot) . . . TM to -IN . . . . . . . . . . . . . . . . . . . . . . . . -0.3 7 VDC + OUT to - OUT....................................... -0.3 -0.5 20 VDC 2250 VDC 40 VDC 2.0 ELECTRICAL CHARACTERISTICS Specifications apply over all line and load conditions unless otherwise noted; Boldface specifications apply over the temperature range of -40°C < TJ < 125 °C (T-Grade); All other specifications are at TJ = 25ºC unless otherwise noted. ATTRIBUTE Input voltage range VIN slew rate SYMBOL VIN CONDITIONS / NOTES No external VC applied VC applied dVIN /dt No Load power dissipation PNL Inrush current peak IINRP IIN_DC K VOUT K = VOUT / VIN, IOUT = 0 A VOUT = VIN • K - IOUT • ROUT, Section 11 DC input current Transfer ratio Output voltage Output current (average) Output current (peak) Output power (average) Efficiency (ambient) Efficiency (hot) Efficiency (over load range) Output resistance (cold) Output resistance (ambient) Output resistance (hot) Switching frequency Output ripple frequency VIN_UV IOUT_AVG IOUT_PK POUT_AVG hAMB hHOT h20% ROUT_COLD ROUT_AMB ROUT_HOT FSW FSW_RP Output voltage ripple VOUT_PP Output inductance (parasitic) LOUT_PAR Output capacitance (internal) COUT_INT Output capacitance (external) COUT_EXT PROTECTION Overvoltage lockout Overvoltage lockout response time constant Output overcurrent trip Short circuit protection trip current Output overcurrent response time constant Short circuit protection response time Thermal shutdown setpoint Reverse inrush current protection TYP 26 0 Module latched shutdown, No external VC applied, IOUT = 12.5 A VIN = 48 V VIN = 26 V to 55 V VIN = 48 V, TC = 25 ºC VIN = 26 V to 55 V, TC = 2 ºC VC enable, VIN = 48 V, COUT = 375 µF, RLOAD = 1957 mΩ VIN UV turn off MIN TPEAK < 10 ms, IOUT_AVG ≤ 12.5 A IOUT_AVG ≤ 12.5 A VIN = 48 V, IOUT = 12.5 A VIN = 26 V to 55 V, IOUT = 12.5 A VIN = 48 V, IOUT = 6.25 A VIN = 48 V, TC = 100°C, IOUT = 12.5 A 2.5 A < IOUT < 12.5 A TC = -40°C, IOUT = 12.5 A TC = 25°C, IOUT = 12.5 A TC = 100°C, IOUT = 12.5 A 19 3.5 5.9 13.5 Module latched shutdown TOVLO Effective internal RC filter IOCP ISCP V/µs 26 V 12.0 14 8 9 W 20 A 8 A V/V V A A W 12.5 18.0 300 94.5 92.0 93.3 94.1 81.0 20.0 32 38.0 1.68 3.36 % 95.0 95.2 32.8 43.4 50.7 1.77 3.54 46.0 55.0 64.0 1.86 3.72 % % mΩ mΩ mΩ MHz MHz 200 400 mV pH 12 58.7 µF 375 µF 60.0 V 7.8 15 35 VDC 95.5 600 55.1 UNIT 55 55 1 1/2 COUT = 0 F, IOUT = 12.5 A, VIN = 48 V, 20 MHz BW, Section 12 Frequency up to 30 MHz, Simulated J-lead model Effective Value at 24 VOUT VTM Standalone Operation. VIN pre-applied, VC enable VIN_OVLO+ MAX 25 µs 35 A A TOCP Effective internal RC filter (Integrative). 6 ms TSCP From detection to cessation of switching (Instantaneous) 1 µs TJ_OTP 125 Reverse Inrush protection disabled for this product. VTM™ Current Multiplier Rev 1.2 vicorpower.com Page 2 of 18 09/2015 800 927.9474 130 135 ºC Not Recommended for New Designs V048x240y012A 3.0 SIGNAL CHARACTERISTICS Specifications apply over all line and load conditions unless otherwise noted; Boldface specifications apply over the temperaturerange of -40°C < TJ < 125°C (T-Grade); All other specifications are at TJ = 25°C unless otherwise noted. • Used to wake up powertrain circuit. • A minimum of 11.5 V must be applied indefinitely for VIN < 26 V to ensure normal operation. • VC slew rate must be within range for a succesful start. SIGNAL TYPE STATE ATTRIBUTE External VC voltage VC current draw VTM CONTROL : VC • PRM™ VC can be used as valid wake-up signal source. • Internal Resistance used in “Adaptive Loop” compensation • VC voltage may be continuously applied SYMBOL VVC_EXT IVC Steady ANALOG INPUT VC internal diode rating VC internal resistor VC internal resistor temperature coefficient VC start up pulse VC slew rate VC inrush current CONDITIONS / NOTES Required for start up, and operation below 26 V. See Section 7. VC = 11.5 V, VIN = 0 V VC = 11.5 V, VIN > 26 V VC = 16.5 V, VIN > 26 V Fault mode. VC > 11.5 V MIN TYP 11.5 16.5 115 0 0 60 100 0.51 DVC_INT RVC-INT MAX UNIT TVC_COEFF 150 mA V kΩ 900 ppm/°C Tpeak 26 V or VC > 11.5 V. • PC pin cannot sink current and will not disable other modules • After successful start up and under no fault condition, PC can be used as during fault mode. a 5 V regulated voltage source with a 2 mA maximum current. Start Up SIGNAL TYPE ANALOG OUTPUT STATE Steady Start Up Enable DIGITAL INPUT / OUPUT Disable Transitional ATTRIBUTE PC voltage PC source current PC resistance (internal) PC source current PC capacitance (internal) PC resistance (external) PC voltage PC voltage (disable) PC pull down current PC disable time PC fault response time VVC_SP dVC/dt IINR_VC SYMBOL VPC IPC_OP RPC_INT IPC_EN CPC_INT RPC_S VPC_EN VPC_DIS IPC_PD TPC_DIS_T TFR_PC V CONDITIONS / NOTES Internal pull down resistor Rev 1.2 vicorpower.com Page 3 of 18 09/2015 800 927.9474 µs µF TYP MAX UNIT 4.7 5.0 50 50 150 100 5.3 2 400 300 1100 60 2 2.5 5.1 VTM™ Current Multiplier µs MIN Section 7 From fault to PC = 2 V V V/µs A 5 100 3 2 V mA kΩ µA pF kΩ V V mA µs µs V048x240y012A Not Recommended for New Designs TEMPERATURE MONITOR : TM • The TM pin monitors the internal temperature of the VTM controller IC • The TM pin has a room temperature setpoint of 3 V within an accuracy of ±5°C. and approximate gain of 10 mV/°C. • Can be used as a "Power Good" flag to verify that the VTM is operating. • Output drives Temperature Shutdown comparator SIGNAL TYPE STATE ANALOG OUTPUT ATTRIBUTE TM voltage TM source current TM gain Steady Disable DIGITAL OUTPUT (FAULT FLAG) Transitional SYMBOL VTM_AMB ITM ATM TM voltage ripple VTM_PP TM voltage TM resistance (internal) TM capacitance (external) TM fault response time VTM_DIS RTM_INT CTM_EXT TFR_TM CONDITIONS / NOTES TJ controller = 27°C MIN TYP MAX UNIT 2.95 3.00 3.05 100 V µA mV/°C 200 mV 50 50 V kΩ pF µs 10 CTM = 0 F, VIN = 48 V, IOUT = 12.5 A 120 Internal pull down resistor 25 From fault to TM = 1.5 V 0 40 10 4.0 TIMING DIAGRAM ISEC 6 7 ISEC ISEC 1 2 3 VC 4 8 d 5 b VVC-EXT a VOVLO VPRI NL ≥ 26 V c e f VSEC TM VTM-AMB PC g 5V 3V a: VC slew rate (dVC/dt) b: Minimum VC pulse rate c: TOVLO_PIN d: TOCP_SEC e: Secondary turn on delay (TON) f: PC disable time (TPC_DIS_T) g: VC to PC delay (TVC_PC) 1. Initiated VC pulse 2. Controller start 3. VPRI ramp up 4. VPRI = VOVLO 5. VPRI ramp down no VC pulse 6. Overcurrent, Secondary 7. Start up on short circuit 8. PC driven low Notes: – Timing and voltage is not to scale – Error pulse width is load dependent VTM™ Current Multiplier Rev 1.2 vicorpower.com Page 4 of 18 09/2015 800 927.9474 V048x240y012A Not Recommended for New Designs 5.0 APPLICATION CHARACTERISTICS The following values, typical of an application environment, are collected at TC = 25ºC unless otherwise noted. See associated figures for general trend data. ATTRIBUTE SYMBOL No load power dissipation Efficiency (ambient) Efficiency (hot) Output resistance (cold) Output resistance (ambient) Output resistance (hot) PNL hAMB hHOT ROUT_COLD ROUT_AMB ROUT_HOT Output voltage ripple VOUT_PP VOUT transient (positive) VOUT_TRAN+ VOUT transient (negative) VOUT_TRAN- CONDITIONS / NOTES TYP UNIT VIN = 48 V, PC enabled VIN = 48 V, IOUT = 12.5 A VIN = 48 V, IOUT = 12.5 A, TC = 100ºC VIN = 48 V, IOUT = 12.5 A, TC = -40ºC VIN = 48 V, IOUT = 12.5 A VIN = 48 V, IOUT = 12.5 A, TC = 100ºC COUT = 0 F, IOUT = 12.5 A, VIN = 48 V, 20 MHz BW, Section 12 IOUT_STEP = 0 A TO 12.5 A, VIN = 48 V, ISLEW = 17 A /us IOUT_STEP = 12.5 A to 0 A, VIN = 48 V ISLEW = 212 A /us 5.8 95.8 95.3 40.5 48.8 56.9 W % % mΩ mΩ mΩ 149 mV 700 mV 700 mV No Load Power Dissipation vs. Line Full Load Efficiency vs. TCASE 98 Full Load Efficiency (%) 11 9 7 5 3 1 96 94 92 26 29 32 35 38 41 43 46 49 52 55 -40 -20 0 Input Voltage (V) -40°C TCASE: 40 60 80 100 Case Temperature (C) 25°C 100°C VIN 26 V : 48 V 55 V Figure 2 — Full load efficiency vs. temperature Figure 1 — No load power dissipation vs. VIN Efficiency & Power Dissipation -40°C Case Efficiency & Power Dissipation 25°C Case 27 97 27 94 24 94 24 91 21 91 21 88 18 88 18 85 15 85 15 82 12 82 12 79 9 79 9 76 6 PD 73 3 70 0 0 1 2 3 4 5 6 7 8 9 10 11 12 Efficiency (%) 97 Power Dissipation (W) Efficiency (%) 20 76 6 PD 73 13 0 0 1 2 3 4 Load Current (A) VIN: 26 V 48 V 55 V 3 70 Power Dissipation (W) Power Dissipation (W) 13 5 6 7 8 9 10 11 12 13 Load Current (A) 26 V 48 V Figure 3 — Efficiency and power dissipation at –40°C 55 V VIN: 26 V 48 V 55 V 26 V 48 V Figure 4 — Efficiency and power dissipation at 25°C VTM™ Current Multiplier Rev 1.2 vicorpower.com Page 5 of 18 09/2015 800 927.9474 55 V V048x240y012A Not Recommended for New Designs ROUT vs. TCASE at VIN = 48 V 94 24 91 21 88 18 85 15 82 12 79 9 6 76 PD 73 3 70 60 ROUT (mW)) 27 Power Dissipation (W) Efficiency Efficiency & Power Dissipation 100°C Case 97 0 1 2 3 4 5 6 7 8 9 10 11 12 40 30 20 0 70 50 -40 13 -20 26 V VIN: 48 V 55 V 26 V 48 V Output Current (A) VRipple (mVPK-PK) 125 100 75 50 25 4 5 6 7 8 9 10 11 12 13 26 V 48 V 20 18 16 14 12 10 8 6 4 2 0 100 10ms Max Continuous 0 Load Current (A) VIN : 80 Safe Operating Area 150 3 60 Figure 6 — ROUT vs. temperature Output Voltage Ripple vs. Load 2 40 Full Load 175 1 20 55 V Figure 5 — Efficiency and power dissipation at 100°C 0 0 Case Temperature (C) Load Current (A) 4 8 12 16 20 Output Voltage (V) 55 V Figure 7 — VRIPPLE vs. IOUT ; No external COUT. Board mounted module, scope setting : 20 MHz analog BW Figure 8 — Safe operating area Figure 9 — Full load ripple, 100 µF CIN; No external COUT. Board mounted module, scope setting : 20 MHz analog BW Figure 10 — Start up from application of VIN; VC pre-applied COUT = 375 µF VTM™ Current Multiplier Rev 1.2 vicorpower.com Page 6 of 18 09/2015 800 927.9474 24 28 Not Recommended for New Designs Figure 11 — Start up from application of VC; VIN pre-applied COUT = 375 µF V048x240y012A Figure 12 – 0 A– Full load transient response: CIN = 100 µF, no external COUT Figure 13 — Full load – 0 A transient response: CIN = 100 µF, no external COUT VTM™ Current Multiplier Rev 1.2 vicorpower.com Page 7 of 18 09/2015 800 927.9474 V048x240y012A Not Recommended for New Designs 6.0 GENERAL CHARACTERISTICS Specifications apply over all line and load conditions unless otherwise noted; Boldface specifications apply over the temperature range of -40ºC < TJ < 125ºC (T-Grade); All Other specifications are at TJ = 25°C unless otherwise noted. ATTRIBUTE MECHANICAL Length Width Height Volume Weight SYMBOL L W H Vol W CONDITIONS / NOTES MIN 32.25 / [1.270] 21.75 / [0.856] 6.48 / [0.255] No heat sink Nickel Palladium Gold Lead finish TYP 32.5 / [1.280] 22.0 / [0.866] 6.73 / [0.265] 4.81 / [0.294] 15.0 / [0.53] MAX UNIT 32.75 / [1.289] 22.25 / [0.876] 6.98 / [0.275] mm/[in] mm/[in] mm/[in] cm3/[in3] g/[oz] 0.51 0.02 0.003 2.03 0.15 0.051 µm -40 -55 -40 -55 125 125 125 125 °C °C °C °C THERMAL Operating temperature Thermal resistance V048x240y012A (T-Grade) VTM48EF240M012A00 (M-Grade) VTM48ET240T012A00 (T-Grade) VTM48ET240M012A00 (M-Grade) Isothermal heat sink and isothermal internal PCB TJ fJC Thermal capacity ASSEMBLY Peak compressive force applied to case (Z-axis) Storage temperature TST ESDHBM ESDCDM SOLDERING Peak temperature during reflow Peak time above 217°C Peak heating rate during reflow Peak cooling rate post reflow MTBF Agency approvals / standards °C/W 5 Ws/°C 6 5.41 125 125 125 125 Supported by J-lead only ESD withstand SAFETY Isolation voltage (hipot) Isolation capacitance Isolation resistance 1 V048x240y012A (T-Grade) VTM48EF240M012A00 (M-Grade) VTM48ET240T012A00 (T-Grade) VTM48ET240M012A00 ( M-Grade) Human Body Model, "JEDEC JESD 22-A114-F" Charge Device Model, "JEDEC JESD 22-C101-D" -40 -65 -40 -65 1000 VDC 400 MSL 4 (Datecode 1528 and later) VHIPOT CIN_OUT RIN_OUT 2250 2500 10 Unpowered unit lbs lbs / in2 °C °C °C °C 60 1.5 1.5 245 90 3 6 °C s °C/s °C/s 3200 3800 VDC pF MΩ MIL-HDBK-217 Plus Parts Count; 25ºC Ground Benign, Stationary, 3.8 Indoors / Computer Profile Telcordia Issue 2 - Method I Case 1; 5.7 Ground Benign, Controlled cTUVus cURus "CE Marked for Low Voltage Directive and RoHS Recast Directive, as applicable" VTM™ Current Multiplier Rev 1.2 vicorpower.com Page 8 of 18 09/2015 800 927.9474 MHrs MHrs Not Recommended for New Designs 7.0 USING THE CONTROL SIGNALS VC, PC, TM, IM The VTM Control (VC) pin is an input pin which powers the internal VCC circuitry when within the specified voltage range of 11.5 V to 16.5 V. This voltage is required for VTM current multiplier start up and must be applied as long as the input is below 26 V. In order to ensure a proper start, the slew rate of the applied voltage must be within the specified range. Some additional notes on the using the VC pin: • In most applications, the VTM module will be powered by an upstream PRM™ regulator which provides a 10 ms VC pulse during start up. In these applications the VC pins of the PRM regulator and VTM current multiplier should be tied together. • The VC voltage can be applied indefinitely allowing for continuous operation down to 0 VIN. • The fault response of the VTM module is latching. A positive edge on VC is required in order to restart the unit. If VC is continuously applied the PC pin may be toggled to restart the VTM module. Primary Control (PC) pin can be used to accomplish the following functions: • Delayed start: Upon the application of VC, the PC pin will source a constant 100 µA current to the internal RC network. Adding an external capacitor will allow further delay in reaching the 2.5 V threshold for module start. • Auxiliary voltage source: Once enabled in regular operational conditions (no fault), each VTM PC provides a regulated 5 V, 2 mA voltage source. • Output disable: PC pin can be actively pulled down in order to disable the module. Pull down impedance shall be lower than 400 Ω. • Fault detection flag: The PC 5 V voltage source is internally turned off as soon as a fault is detected. It is important to notice that PC doesn’t have current sink capability. Therefore, in an array, PC line will not be capable of disabling neighboring modules if a fault is detected. • Fault reset: PC may be toggled to restart the unit if VC is continuously applied. Temperature Monitor (TM) pin provides a voltage proportional to the absolute temperature of the converter control IC. It can be used to accomplish the following functions: • Monitor the control IC temperature: The temperature in Kelvin is equal to the voltage on the TM pin scaled by 100. (i.e. 3.0 V = 300 K = 27ºC). If a heat sink is applied, TM can be used to thermally protect the system. • Fault detection flag: The TM voltage source is internally turned off as soon as a fault is detected. For system monitoring purposes (microcontroller interface) faults are detected on falling edges of TM signal. V048x240y012A 8.0 START UP BEHAVIOR Depending on the sequencing of the VC with respect to the input voltage, the behavior during start up will vary as follows: • Normal operation (VC applied prior to VIN ): In this case the controller is active prior to ramping the input. When the input voltage is applied, the VTM module output voltage will track the input (See Figure 10). The inrush current is determined by the input voltage rate of rise and output capacitance. If the VC voltage is removed prior to the input reaching 26 V, the VTM may shut down. • Stand-alone operation (VC applied after VIN ): In this case the VTM output will begin to rise upon the application of the VC voltage (See Figure 11). The Adaptive Soft Start Circuit (See Section 11) may vary the ouput rate of rise in order to limit the inrush current to its maximum level. When starting into high capacitance, or a short, the output current will be limited for a maximum of 1200 µsec. After this period, the Adaptive Soft Start Circuit will time out and the VTM module may shut down. No restart will be attempted until VC is re-applied or PC is toggled. The maximum output capacitance is limited to 375 µF in this mode of operation to ensure a sucessful start. 9.0 THERMAL CONSIDERATIONS VI Chip® products are multi-chip modules whose temperature distribution varies greatly for each part number as well as with the input /output conditions, thermal management and environmental conditions. Maintaining the top of the V048x240y012A case to less than 100ºC will keep all junctions within the VI Chip module below 125ºC for most applications. The percent of total heat dissipated through the top surface versus through the J-lead is entirely dependent on the particular mechanical and thermal environment. The heat dissipated through the top surface is typically 60%. The heat dissipated through the J-lead onto the PCB board surface is typically 40%. Use 100% top surface dissipation when designing for a conservative cooling solution. It is not recommended to use a VI Chip module for an extended period of time at full load without proper heat sinking. VTM™ Current Multiplier Rev 1.2 vicorpower.com Page 9 of 18 09/2015 800 927.9474 PC -VIN VC PC Pull-Up & Source R VC_INT +VINI VTM™ Current Multiplier Rev 1.2 vicorpower.com Page 10 of 18 09/2015 800 927.9474 1000 pF 2.5 V V DD D VC_INT CIN 100 A 18 V V DD Regulator Supply 150 K 1.5 K 10.5 V 5V 2 mA 2.5 V Enable Enable Gate Drive Supply OVLO UVLO V IN Adaptive Soft Start V DD Fault Logic Enable Modulator Enable Slow Current Limit Cr V REF Fast Current Limit Q4 Lr Primary Stage & Resonant Tank Over Current Protection Differential Primary Current Sensing Q2 Overtemperature Protection Primary Gate Drive Q1 Q3 Temperature Dependent Voltage Source V REF Secondary Gate Drive Q6 40 K Power Transformer 1K Q5 0.01 F Synchronous Rectification +VOUT TM -VOUT COUT Not Recommended for New Designs V048x240y012A 10.0 VTM MODULE BLOCK DIAGRAM V048x240y012A Not Recommended for New Designs 11.0 SINE AMPLITUDE CONVERTERTM POINT OF LOAD CONVERSION The Sine Amplitude Converter (SAC) uses a high frequency resonant tank to move energy from input to output. (The resonant tank is formed by Cr and leakage inductance Lr in the power transformer windings as shown in the VTM module Block Diagram. See Section 10). The resonant LC tank, operated at high frequency, is amplitude modulated as a function of input voltage and output current. A small amount of capacitance embedded in the input and output stages of the module is sufficient for full functionality and is key to achieving power density. The V048x240y012A SAC can be simplified into the following model: 2000 pH IOUT IOUT LIN = 0.6 nH LOUT = 600 pH 43.4 mΩ + VIN V IN OUT RROUT R RCIN CIN 2.2 mΩ CCININ 0.006 Ω V•I 1/2 • IOUT 2 µF IIQQ 123 mA RRCOUT COUT + + – – + 417 µΩ 1/2 • VIN COUT COUT 12 µF VOUT V OUT K – – Figure 14 — VI Chip® module AC model At no load: VOUT = VIN • K (1) The use of DC voltage transformation provides additional interesting attributes. Assuming that ROUT = 0 Ω and IQ = 0 A, Eq. (3) now becomes Eq. (1) and is essentially load independent, resistor R is now placed in series with VIN as shown in Figure 15. K represents the “turns ratio” of the SAC. Rearranging Eq (1): K= VOUT VIN (2) R R VVin IN + – SAC™ SAC 1/32 KK == 1/32 V Vout OUT In the presence of load, VOUT is represented by: VOUT = VIN • K – IOUT • ROUT (3) Figure 15 — K = 1/32 Sine Amplitude Converter™ with series input resistor and IOUT is represented by: IOUT = IIN – IQ K (4) ROUT represents the impedance of the SAC, and is a function of the RDSON of the input and output MOSFETs and the winding resistance of the power transformer. IQ represents the quiescent current of the SAC control and gate drive circuitry. The relationship between VIN and VOUT becomes: VOUT = (VIN – IIN • R) • K (5) Substituting the simplified version of Eq. (4) (IQ is assumed = 0 A) into Eq. (5) yields: VOUT = VIN • K – IOUT • R • K2 VTM™ Current Multiplier Rev 1.2 vicorpower.com Page 11 of 18 09/2015 800 927.9474 (6) V048x240y012A Not Recommended for New Designs This is similar in form to Eq. (3), where ROUT is used to represent the characteristic impedance of the SAC™. However, in this case a real R on the input side of the SAC is effectively scaled by K2 with respect to the output. Assuming that R = 1 Ω, the effective R as seen from the secondary side is 0.98 mΩ, with K = 1/32 as shown in Figure 15. A similar exercise should be performed with the additon of a capacitor or shunt impedance at the input to the SAC. A switch in series with VIN is added to the circuit. This is depicted in Figure 16. SS VVin IN + – C C SAC™ SAC K = 1/32 K = 1/32 VVout OUT Figure 16 — Sine Amplitude Converter™ with input capacitor A change in VIN with the switch closed would result in a change in capacitor current according to the following equation: IC(t) = C dVIN dt PDISSIPATED = PNL + PROUT Assume that with the capacitor charged to VIN, the switch is opened and the capacitor is discharged through the idealized SAC. In this case, (8) POUT = PIN – PDISSIPATED = PIN – PNL – PROUT C K2 • h = = dVOUT dt (9) The equation in terms of the output has yielded a K2 scaling factor for C, specified in the denominator of the equation. A K factor less than unity, results in an effectively larger capacitance on the output when expressed in terms of the input. With a K= 1/32 as shown in Figure 16, C=1 µF would appear as C=1024 µF when viewed from the output. (11) The above relations can be combined to calculate the overall module efficiency: Substituting Eq. (1) and (8) into Eq. (7) reveals: IOUT = (10) Therefore, (7) IC = IOUT • K Low impedance is a key requirement for powering a highcurrent, low voltage load efficiently. A switching regulation stage should have minimal impedance while simultaneously providing appropriate filtering for any switched current. The use of a SAC between the regulation stage and the point of load provides a dual benefit of scaling down series impedance leading back to the source and scaling up shunt capacitance or energy storage as a function of its K factor squared. However, the benefits are not useful if the series impedance of the SAC is too high. The impedance of the SAC must be low, i.e. well beyond the crossover frequency of the system. A solution for keeping the impedance of the SAC low involves switching at a high frequency. This enables small magnetic components because magnetizing currents remain low. Small magnetics mean small path lengths for turns. Use of low loss core material at high frequencies also reduces core losses. The two main terms of power loss in the VTM module are: - No load power dissipation (PNL ): defined as the power used to power up the module with an enabled powertrain at no load. - Resistive loss (ROUT): refers to the power loss across the VTM modeled as pure resistive impedance. POUT = PIN – PNL – PROUT PIN PIN VIN • IIN – PNL – (IOUT)2 • ROUT VIN • IIN = 1– ( ) PNL + (IOUT)2 • ROUT VIN • IIN VTM™ Current Multiplier Rev 1.2 vicorpower.com Page 12 of 18 09/2015 800 927.9474 (12) Not Recommended for New Designs 12.0 INPUT AND OUTPUT FILTER DESIGN A major advantage of a SAC system versus a conventional PWM converter is that the former does not require large functional filters. The resonant LC tank, operated at extreme high frequency, is amplitude modulated as a function of input voltage and output current and efficiently transfers charge through the isolation transformer. A small amount of capacitance embedded in the input and output stages of the module is sufficient for full functionality and is key to achieving high power density. This paradigm shift requires system design to carefully evaluate external filters in order to: 1.Guarantee low source impedance. To take full advantage of the VTM module dynamic response, the impedance presented to its input terminals must be low from DC to approximately 5 MHz. Input capacitance may be added to improve transient performance or compensate for high source impedance. 2.Further reduce input and /or output voltage ripple without sacrificing dynamic response. Given the wide bandwidth of the VTM module, the source response is generally the limiting factor in the overall system response. Anomalies in the response of the source will appear at the output of the VTM module multiplied by its K factor. 3.Protect the module from overvoltage transients imposed by the system that would exceed maximum ratings and cause failures. The VI Chip® module input/output voltage ranges must not be exceeded. An internal overvoltage lockout function prevents operation outside of the normal operating input range. Even during this condition, the powertrain is exposed to the applied voltage and power MOSFETs must withstand it. V048x240y012A 13.0 CAPACITIVE FILTERING CONSIDERATIONS FOR A SINE AMPLITUDE CONVERTER™ It is important to consider the impact of adding input and output capacitance to a Sine Amplitude Converter on the system as a whole. Both the capacitance value and the effective impedance of the capacitor must be considered. A Sine Amplitude Converter has a DC ROUT value which has already been discussed in section 11. The AC ROUT of the SAC contains several terms: • Resonant tank impedance • Input lead inductance and internal capacitance • Output lead inductance and internal capacitance The values of these terms are shown in the behavioral model in section 11. It is important to note on which side of the transformer these impedances appear and how they reflect across the transformer given the K factor. The overall AC impedance varies from model to model. For most models it is dominated by DC ROUT value from DC to beyond 500 KHz. The behavioral model in section 11 should be used to approximate the AC impedance of the specific model. Any capacitors placed at the output of the VTM module reflect back to the input of the module by the square of the K factor (Eq. 9) with the impedance of the module appearing in series. It is very important to keep this in mind when using a PRM™ regulator to power the VTM module. Most PRM modules have a limit on the maximum amount of capacitance that can be applied to the output. This capacitance includes both the PRM output capacitance and the VTM module output capacitance reflected back to the input. In PRM module remote sense applications, it is important to consider the reflected value of VTM module output capacitance when designing and compensating the PRM module control loop. Capacitance placed at the input of the VTM module appear to the load reflected by the K factor with the impedance of the VTM module in series. In step-down ratios, the effective capacitance is increased by the K factor. The effective ESR of the capacitor is decreased by the square of the K factor, but the impedance of the module appears in series. Still, in most step-down VTM modules an electrolytic capacitor placed at the input of the module will have a lower effective impedance compared to an electrolytic capacitor placed at the output. This is important to consider when placing capacitors at the output of the module. Even though the capacitor may be placed at the output, the majority of the AC current will be sourced from the lower impedance, which in most cases will be the module. This should be studied carefully in any system design using a module. In most cases, it should be clear that electrolytic output capacitors are not necessary to design a stable, well-bypassed system. VTM™ Current Multiplier Rev 1.2 vicorpower.com Page 13 of 18 09/2015 800 927.9474 Not Recommended for New Designs 14.0 CURRENT SHARING The SAC topology bases its performance on efficient transfer of energy through a transformer without the need of closed loop control. For this reason, the transfer characteristic can be approximated by an ideal transformer with some resistive drop and positive temperature coefficient. This type of characteristic is close to the impedance characteristic of a DC power distribution system, both in behavior (AC dynamic) and absolute value (DC dynamic). When connected in an array with the same K factor, the VTM module will inherently share the load current (typically 5%) with parallel units according to the equivalent impedance divider that the system implements from the power source to the point of load. Some general recommendations to achieve matched array impedances: • Dedicate common copper planes within the PCB to deliver and return the current to the modules. • Provide the PCB layout as symmetric as possible. • Apply same input / output filters (if present) to each unit. 16.0 REVERSE OPERATION The V048x240y012A is capable of reverse operation. If a voltage is present at the output which satisfies the condition VOUT > VIN • K at the time the VC voltage is applied, or after the unit has started, then energy will be transferred from secondary to primary. The input to output ratio will be maintained. The V048x240y012A will continue to operate in reverse as long as the input and output are within the specified limits. The V048x240y012A has not been qualified for continuous operation (>10 ms) in the reverse direction. For further details see AN:016 Using BCM® Bus Converters in High Power Arrays. VIN ZIN_EQ1 VTM™1 ZOUT_EQ1 VOUT RO_1 ZIN_EQ2 VTM™2 ZOUT_EQ2 RO_2 + – DC Load ZIN_EQn VTM™n V048x240y012A ZOUT_EQn RO_n Figure 17 — VTM module array 15.0 FUSE SELECTION In order to provide flexibility in configuring power systems VI Chip® products are not internally fused. Input line fusing of VI Chip products is recommended at system level to provide thermal protection in case of catastrophic failure. The fuse shall be selected by closely matching system requirements with the following characteristics: • Current rating (usually greater than maximum current of VTM module) • Maximum voltage rating (usually greater than the maximum possible input voltage) • Ambient temperature • Nominal melting I2t VTM™ Current Multiplier Rev 1.2 vicorpower.com Page 14 of 18 09/2015 800 927.9474 Not Recommended for New Designs V048x240y012A 17.1 J-LEAD PACKAGE MECHANICAL DRAWING mm (inch) NOTES: mm 2. DIMENSIONS ARE inch . UNLESS OTHERWISE SPECIFIED, TOLERANCES ARE: 3. .X / [.XX] = +/-0.25 / [.01]; .XX / [.XXX] = +/-0.13 / [.005] 4. PRODUCT MARKING ON TOP SURFACE DXF and PDF files are available on vicorpower.com 17.2 J-LEAD PACKAGE RECOMMENDED LAND PATTERN 3. .X / [.XX] = +/-0.25 / [.01]; .XX / [.XXX] = +/-0.13 / [.005] mm 2. DIMENSIONS ARE inch . UNLESS OTHERWISE SPECIFIED, TOLERANCES ARE: 4. PRODUCT MARKING ON TOP SURFACE DXF and PDF files are available on vicorpower.com VTM™ Current Multiplier Rev 1.2 vicorpower.com Page 15 of 18 09/2015 800 927.9474 Not Recommended for New Designs V048x240y012A 17.3 THROUGH-HOLE PACKAGE MECHANICAL DRAWING mm (inch) NOTES: mm 2. DIMENSIONS ARE inch . UNLESS OTHERWISE SPECIFIED, TOLERANCES ARE: 3. .X / [.XX] = +/-0.25 / [.01]; .XX / [.XXX] = +/-0.13 / [.005] 4. PRODUCT MARKING ON TOP SURFACE DXF and PDF files are available on vicorpower.com 17.4 THROUGH-HOLE PACKAGE RECOMMENDED LAND PATTERN 3. .X / [.XX] = +/-0.25 / [.01]; .XX / [.XXX] = +/-0.13 / [.005] mm 2. DIMENSIONS ARE inch . UNLESS OTHERWISE SPECIFIED, TOLERANCES ARE: 4. PRODUCT MARKING ON TOP SURFACE DXF and PDF files are available on vicorpower.com VTM™ Current Multiplier Rev 1.2 vicorpower.com Page 16 of 18 09/2015 800 927.9474 Not Recommended for New Designs V048x240y012A 17.5 RECOMMENDED HEAT SINK PUSH PIN LOCATION (NO GROUNDING CLIPS) (WITH GROUNDING CLIPS) Notes: 1. Maintain 3.50 (0.138) Dia. keep-out zone free of copper, all PCB layers. 2. (A) Minimum recommended pitch is 39.50 (1.555). This provides 7.00 (0.275) component edge-to-edge spacing, and 0.50 (0.020) clearance between Vicor heat sinks. (B) Minimum recommended pitch is 41.00 (1.614). This provides 8.50 (0.334) component edge-to-edge spacing, and 2.00 (0.079) clearance between Vicor heat sinks. 3. VI Chip® module land pattern shown for reference only; actual land pattern may differ. Dimensions from edges of land pattern to push–pin holes will be the same for all full-size VI Chip® products. 5. Unless otherwise specified: Dimensions are mm (inches) tolerances are: x.x (x.xx) = ±0.3 (0.01) x.xx (x.xxx) = ±0.13 (0.005) 4. RoHS compliant per CST–0001 latest revision. 6. Plated through holes for grounding clips (33855) shown for reference, heat sink orientation and device pitch will dictate final grounding solution. 17.6 VTM MODULE PIN CONFIGURATION 4 3 2 +Out B C C D D F G H H J J K K +Out -Out +In E E -Out 1 A A B L L M M N N P P R R TM VC PC -In T T Signal Name +In –In TM VC PC +Out –Out Bottom View VTM™ Current Multiplier Rev 1.2 vicorpower.com Page 17 of 18 09/2015 800 927.9474 Pin Designation A1-E1, A2-E2 L1-T1, L2-T2 H1, H2 J1, J2 K1, K2 A3-D3, A4-D4, J3-M3, J4-M4 E3-H3, E4-H4, N3-T3, N4-T4 Not Recommended for New Designs V048x240y012A 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. Vicor’s Standard Terms and Conditions All sales are subject to Vicor’s Standard Terms and Conditions of Sale, which are available on Vicor’s webpage or upon request. Product Warranty In Vicor’s standard terms and conditions of sale, Vicor warrants that its products are free from non-conformity to its Standard Specifications (the “Express Limited Warranty”). This warranty is extended only to the original Buyer for the period expiring two (2) years after the date of shipment and is not transferable. UNLESS OTHERWISE EXPRESSLY STATED IN A WRITTEN SALES AGREEMENT SIGNED BY A DULY AUTHORIZED VICOR SIGNATORY, VICOR DISCLAIMS ALL REPRESENTATIONS, LIABILITIES, AND WARRANTIES OF ANY KIND (WHETHER ARISING BY IMPLICATION OR BY OPERATION OF LAW) WITH RESPECT TO THE PRODUCTS, INCLUDING, WITHOUT LIMITATION, ANY WARRANTIES OR REPRESENTATIONS AS TO MERCHANTABILITY, FITNESS FOR PARTICULAR PURPOSE, INFRINGEMENT OF ANY PATENT, COPYRIGHT, OR OTHER INTELLECTUAL PROPERTY RIGHT, OR ANY OTHER MATTER. This warranty does not extend to products subjected to misuse, accident, or improper application, maintenance, or storage. 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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: 5,945,130; 6,403,009; 6,710,257; 6,911,848; 6,930,893; 6,934,166; 6,940,013; 6,969,909; 7,038,917; 7,145,186; 7,166,898; 7,187,263; 7,202,646; 7,361,844; D496,906; D505,114; D506,438; D509,472; and for use under 6,975,098 and 6,984,965. Vicor Corporation 25 Frontage Road Andover, MA, USA 01810 Tel: 800-735-6200 Fax: 978-475-6715 email Customer Service: custserv@vicorpower.com Technical Support: apps@vicorpower.com VTM™ Current Multiplier Rev 1.2 vicorpower.com Page 18 of 18 09/2015 800 927.9474