ADUM5000

Isolated DC-to-DC Converter ADuM5000 FEATURES isoPower, integrated isolated dc-to-dc converter Regulated 3.3 V or 5 V output Up to 500 mW output power 16-lead SOIC package with >8 mm creepage High temperature operation: 105°C maximum High common-mode transient immunity: >25 kV/μs Thermal overload protection Safety and regulatory approvals UL recognition 2500 V rms for 1 minute per UL 1577 CSA Component Acceptance Notice #5A (pending) VDE certificate of conformity (pending) DIN V VDE V 0884-10 (VDE V 0884-10):2006-12 VIORM = 560 V peak VDD1 GND1 NC RCIN RCOUT RCSEL VDD1 GND1 FUNCTIONAL BLOCK DIAGRAM 1 OSC RECT REG 16 VISO 15 GNDISO 14 NC 13 VSEL 12 NC 11 NC 10 VISO 2 3 4 5 6 7 8 ADuM5000 Figure 1. 9 GNDISO APPLICATIONS RS-232/RS-422/RS-485 transceivers Industrial field bus isolation Power supply startups and gate drives Isolated sensor interfaces Industrial PLCs GENERAL DESCRIPTION The ADuM50001 is an isolated dc-to-dc converter based on the Analog Devices, Inc., iCoupler® technology. The dc-to-dc converter in this device provides regulated, isolated power in several combinations of input and output voltage as listed in Table 1. The Analog Devices chip-scale transformer iCoupler technology transfers isolated power in this dc-to-dc converter with up to 33% efficiency. The result is a small form factor, total isolation solution. Higher output power levels are obtained by using the ADuM5000 to augment the power output of ADuM5401, ADuM5402, ADuM5403, ADuM5404, and ADuM520x iCouplers with isoPower®. isoPower uses high frequency switching elements to transfer power through its transformer. Special care must be taken during printed circuit board (PCB) layout to meet emissions standards. Refer to the AN-0971 application note for board layout recommendations. Table 1. Input Voltage 5V 5V 3.3 V Output Voltage 5V 3.3 V 3.3 V Output Power 500 mW 330 mW 200 mW 1 Protected by U.S. Patents 5,952,849; 6,873,065; 6,903,578; and 7,075,329; other patents pending. Rev. 0 Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other rights of third parties that may result from its use. Specifications subject to change without notice. No license is granted by implication or otherwise under any patent or patent rights of Analog Devices. Trademarks and registered trademarks are the property of their respective owners. One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. Tel: 781.329.4700 www.analog.com Fax: 781.461.3113 ©2008 Analog Devices, Inc. All rights reserved. 07539-001 ADuM5000 TABLE OF CONTENTS Features .............................................................................................. 1  Applications ....................................................................................... 1  Functional Block Diagram .............................................................. 1  General Description ......................................................................... 1  Revision History ............................................................................... 2  Specifications..................................................................................... 3  Electrical Characteristics—5 V Primary Input Supply/5 V Secondary Isolated Supply .......................................................... 3  Electrical Characteristics—3.3 V Primary Input Supply/3.3 V Secondary Isolated Supply .......................................................... 3  Electrical Characteristics—5 V Primary Input Supply/3.3 V Secondary Isolated Supply .......................................................... 4  Package Characteristics ............................................................... 5  Regulatory Information ............................................................... 5  Insulation and Safety-Related Specifications ............................ 5  DIN V VDE V 0884-10 (VDE V 0884-10) Insulation Characteristics .............................................................................. 6  Recommended Operating Conditions .......................................7  Absolute Maximum Ratings ............................................................8  ESD Caution...................................................................................8  Pin Configuration and Function Descriptions..............................9  Typical Performance Characteristics ........................................... 10  Applications Information .............................................................. 12  PCB Layout ................................................................................. 12  EMI Considerations ................................................................... 12  Thermal Analysis ....................................................................... 12  Current Limit and Thermal Overload Protection ................. 13  Power Considerations ................................................................ 13  Increasing Available Power ....................................................... 13  Insulation Lifetime ..................................................................... 14  Outline Dimensions ....................................................................... 15  Ordering Guide .......................................................................... 15  REVISION HISTORY 10/08—Revision 0: Original Version Rev. 0 | Page 2 of 16 ADuM5000 SPECIFICATIONS ELECTRICAL CHARACTERISTICS—5 V PRIMARY INPUT SUPPLY/5 V SECONDARY ISOLATED SUPPLY 4.5 V ≤ VDD1 ≤ 5.5 V, VSEL = VISO; each voltage is relative to its respective ground. All minimum/maximum specifications apply over the entire recommended operating range, unless otherwise noted. All typical specifications are at TA = 25°C, VDD = 5.0 V, VISO = 5.0 V, and VSEL = VISO. Table 2. Parameter DC-to-DC CONVERTER POWER SUPPLY Setpoint Line Regulation Load Regulation Output Ripple Output Noise Switching Frequency PWM Frequency IDD1 Supply Current, Full VISO Load Maximum Output Supply Current Efficiency At Maximum Output Supply Current IDD1 Supply Current, No VISO Load Undervoltage Lockout, VDD1 and VISO Supply Positive Going Threshold Negative Going Threshold Hysteresis Symbol VISO VISO(LINE) VISO(LOAD) VISO(RIP) VISO(N) fOSC fPWM IDD1(MAX) IISO(MAX) Min 4.7 Typ 5.0 1 1 75 200 180 625 290 34 IDD1(Q) 4 15 Max 5.4 5 Unit V mV/V % mV p-p mV p-p MHz kHz mA mA % mA Test Conditions IISO = 0 mA IISO = 50 mA, VDD1 = 4.5 V to 5.5 V IISO = 10 mA to 90 mA 20 MHz bandwidth, CBO = 0.1 μF||10 μF, IISO = 90 mA CBO = 0.1 μF||10 μF, IISO = 90 mA 100 IISO = 100 mA VISO > 4.5 V IISO = 100 mA IISO = 0 mA VUV+ VUV− VUVH 2.7 2.4 0.3 V V V ELECTRICAL CHARACTERISTICS—3.3 V PRIMARY INPUT SUPPLY/3.3 V SECONDARY ISOLATED SUPPLY 3.0 V ≤ VDD1 ≤ 3.6 V, VSEL = GNDISO; each voltage is relative to its respective ground. All minimum/maximum specifications apply over the entire recommended operating range, unless otherwise noted. All typical specifications are at TA = 25°C, VDD = 3.3 V, VISO = 3.3 V, and VSEL = GNDISO. Table 3. Parameter DC-to-DC CONVERTER POWER SUPPLY Setpoint Line Regulation Load Regulation Output Ripple Output Noise Switching Frequency PWM Frequency IDD1 Supply Current, Full VISO Load Maximum Output Supply Current Efficiency At Maximum Output Supply Current IDD1 Supply Current, No VISO Load Undervoltage Lockout, VDD1 and VISO Supply Positive Going Threshold Negative Going Threshold Hysteresis Symbol VISO VISO(LINE) VISO(LOAD) VISO(RIP) VISO(N) fOSC fPWM IDD1(MAX) IISO(MAX) Min 3.0 Typ 3.3 1 1 50 130 180 625 175 35 IDD1(Q) 3 12 Max 3.6 5 Unit V mV/V % mV p-p mV p-p MHz kHz mA mA % mA Test Conditions IISO = 0 mA IISO = 30 mA, VDD1 = 3.0 V to 3.6 V IISO = 6 mA to 54 mA 20 MHz bandwidth, CBO = 0.1 μF||10 μF, IISO = 54 mA CBO = 0.1 μF||10 μF, IISO = 54 mA 60 IISO = 60 mA VISO > 3.0 V IISO = 60 mA IISO = 0 mA VUV+ VUV− VUVH 2.7 2.4 0.3 V V V Rev. 0 | Page 3 of 16 ADuM5000 ELECTRICAL CHARACTERISTICS—5 V PRIMARY INPUT SUPPLY/3.3 V SECONDARY ISOLATED SUPPLY 4.5 V ≤ VDD1 ≤ 5.5 V, VSEL = GNDISO, each voltage is relative to its respective ground. All minimum/maximum specifications apply over the entire recommended operating range, unless otherwise noted. All typical specifications are at TA = 25°C, VDD = 5.0 V, VISO = 3.3 V, and VSEL = GNDISO. Table 4. Parameter DC-to-DC CONVERTER POWER SUPPLY Setpoint Line Regulation Load Regulation Output Ripple Output Noise Switching Frequency PWM Frequency IDD1 Supply Current, Full VISO Load Maximum Output Supply Current Efficiency At Maximum Output Supply Current IDD1 Supply Current, No VISO Load Undervoltage Lockout, VDD1 and VISO Supply Positive Going Threshold Negative Going Threshold Hysteresis Symbol VISO VISO(LINE) VISO(LOAD) VISO(RIP) VISO(N) fOSC fPWM IDD1(MAX) IISO(MAX) Min 3.0 Typ 3.3 1 1 50 130 180 625 250 28 IDD1(Q) 3 12 Max 3.6 5 Unit V mV/V % mV p-p mV p-p MHz kHz mA mA % mA Test Conditions IISO = 0 mA IISO = 50 mA, VDD1 = 4.5 V to 5.5 V IISO = 10 mA to 100 mA 20 MHz bandwidth, CBO = 0.1 μF||10 μF, IISO = 90 mA CBO = 0.1 μF||10 μF, IISO = 90 mA 100 IISO = 100 mA VISO > 3.0 V IISO = 100 mA IISO = 0 mA VUV+ VUV− VUVH 2.7 2.4 0.3 V V V Rev. 0 | Page 4 of 16 ADuM5000 PACKAGE CHARACTERISTICS Table 5. Parameter RESISTANCE AND CAPACITANCE Resistance (Input-to-Output) 1 Capacitance (Input-to-Output)1 Input Capacitance 2 IC Junction-to-Ambient Thermal Resistance Symbol RI-O CI-O CI θJA Min Typ 1012 2.2 4.0 45 Max Unit Ω pF pF °C/W Test Conditions f = 1 MHz Thermocouple is located at the center of the package underside; test conducted on a 4-layer board with thin traces 3 TJ rising THERMAL SHUTDOWN Thermal Shutdown Threshold Thermal Shutdown Hysteresis 1 2 3 TSSD TSSD-HYS 150 20 °C °C This device is considered a 2-terminal device; Pin 1 through Pin 8 are shorted together, and Pin 9 through Pin 16 are shorted together. Input capacitance is from any input data pin to ground. Refer to the Power Considerations section for thermal model definitions. REGULATORY INFORMATION The ADuM5000 is approved by the organizations listed in Table 6. Refer to Table 11 and the Insulation Lifetime section for details regarding recommended maximum working voltages for specific cross isolation waveforms and insulation levels. Table 6. UL Recognized under 1577 component recognition program 1 Single insulation, 2500 V rms isolation voltage File E214100 1 2 CSA (Pending) Approved under CSA Component Acceptance Notice #5A Reinforced insulation per CSA 60950-1-03 and IEC 60950-1, 400 V rms (566 V peak) maximum working voltage File 205078 VDE (Pending) Certified according to DIN V VDE V 0884-10 (VDE V 0884-10):2006-12 2 Reinforced insulation, 560 V peak File 2471900-4880-0001 In accordance with UL 1577, each ADuM5000 is proof tested by applying an insulation test voltage ≥ 3000 V rms for 1 sec (current leakage detection limit = 5 μA). In accordance with DIN V VDE V 0884-10, each ADuM5000 is proof tested by applying an insulation test voltage ≥ 1050 V peak for 1 sec (partial discharge detection limit = 5 pC). The * marking branded on the component designates DIN V VDE V 0884-10 approval. INSULATION AND SAFETY-RELATED SPECIFICATIONS Table 7. Parameter Rated Dielectric Insulation Voltage Minimum External Air Gap (Clearance) Minimum External Tracking (Creepage) Minimum Internal Gap (Internal Clearance) Tracking Resistance (Comparative Tracking Index) Isolation Group Symbol Value 2500 L(I01) >8 min L(I02) Unit Conditions V rms 1-minute duration mm Measured from input terminals to output terminals, shortest distance through air >8 min mm Measured from input terminals to output terminals, shortest distance path along body 0.017 min mm Distance through the insulation >175 V DIN IEC 112/VDE 0303 Part 1 IIIa Material Group (DIN VDE 0110, 1/89, Table 1) CTI Rev. 0 | Page 5 of 16 ADuM5000 DIN V VDE V 0884-10 (VDE V 0884-10) INSULATION CHARACTERISTICS This power module is suitable for reinforced electrical isolation only within the safety limit data. Maintenance of the safety data is ensured by protective circuits. The * marking on packages denotes DIN V VDE V 0884-10 approval. Table 8. Description Installation Classification per DIN VDE 0110 For Rated Mains Voltage ≤ 150 V rms For Rated Mains Voltage ≤ 300 V rms For Rated Mains Voltage ≤ 400 V rms Climatic Classification Pollution Degree per DIN VDE 0110, Table 1 Maximum Working Insulation Voltage Input-to-Output Test Voltage Method b1 Method a After Environmental Tests Subgroup 1 After Input and/or Safety Test Subgroup 2 and Subgroup 3 Highest Allowable Overvoltage Safety-Limiting Values Case Temperature Side 1 IDD1 Current Insulation Resistance at TS Conditions Symbol Characteristic I to IV I to III I to II 40/105/21 2 560 1050 Unit VIORM VIORM × 1.875 = VPR, 100% production test, tm = 1 sec, partial discharge < 5 pC VIORM × 1.6 = VPR, tm = 60 sec, partial discharge < 5 pC VIORM × 1.2 = VPR, tm = 60 sec, partial discharge < 5 pC Transient overvoltage, tTR = 10 sec Maximum value allowed in the event of a failure (see Figure 2) VTR VPR VPR V peak V peak 896 672 4000 V peak V peak V peak VIO = 500 V TS IS1 RS 150 555 >109 °C mA Ω Thermal Derating Curve 600 SAFE OPERATING VDD1 CURRENT (mA) 500 400 300 200 100 0 50 100 150 AMBIENT TEMPERATURE (°C) 200 Figure 2. Thermal Derating Curve, Dependence of Safety Limiting Values on Case Temperature, per DIN EN 60747-5-2 Rev. 0 | Page 6 of 16 07539-002 0 ADuM5000 RECOMMENDED OPERATING CONDITIONS Table 9. Parameter TEMPERATURE Operating Temperature SUPPLY VOLTAGES VDD @ VSEL = 0 V VDD @ VSEL = 5 V MINIMUM POWER ON SLEW RATE Symbol TA VDD VDD VSLEW Min −40 2.7 4.5 150 Max +105 5.5 5.5 Unit °C Each voltage is relative to its respective ground V V V/ms Comments Rev. 0 | Page 7 of 16 ADuM5000 ABSOLUTE MAXIMUM RATINGS Ambient temperature = 25°C, unless otherwise noted. Table 10. Parameter Storage Temperature (TST) Ambient Operating Temperature (TA) Supply Voltages (VDD, VISO)1 Input Voltage (CTR,RCIN, VSEL)1, 2 Output Voltage (RCOUT)1, 2 Average Total Output Current3 IISO Common-Mode Transients4 1 2 Table 11. Maximum Continuous Working Voltage1 Parameter AC Voltage Bipolar Waveform Unipolar Waveform Basic Insulation Max 424 Unit V peak Reference Standard 50-year minimum lifetime Maximum approved working voltage per IEC 60950-1 Maximum approved working voltage per IEC 60950-1 and VDE V 0884-10 Maximum approved working voltage per IEC 60950-1 Maximum approved working voltage per IEC 60950-1 and VDE V 0884-10 Rating −55°C to +150°C −40°C to +105°C −0.5 V to +7.0 V −0.5 V to VDDI + 0.5 V −0.5 V to VDDO + 0.5 V 100 mA −100 kV/μs to +100 kV/μs 600 V peak Reinforced Insulation 560 V peak Each voltage is relative to its respective ground. VDDI and VDDO refer to the supply voltages on the input and output sides of a given channel, respectively. See the PCB Layout section. 3 See Figure 2 for maximum rated current values for various temperatures. 4 Refers to common-mode transients across the insulation barrier. Commonmode transients exceeding the absolute maximum ratings may cause latch-up or permanent damage. DC Voltage Basic Insulation 600 V peak Reinforced Insulation 560 V peak Stresses above those listed under Absolute Maximum Ratings may cause permanent damage to the device. This is a stress rating only; functional operation of the device at these or any other conditions above those indicated in the operational section of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. 1 Refers to continuous voltage magnitude imposed across the isolation barrier. See the Insulation Lifetime section for more details. ESD CAUTION Rev. 0 | Page 8 of 16 ADuM5000 PIN CONFIGURATION AND FUNCTION DESCRIPTIONS VDD1 1 GND1 2 NC 3 RCIN 4 RCOUT 5 RCSEL 6 VDD1 7 GND1 8 NC = NO CONNECT 16 15 VISO GNDISO NC VSEL NC NC GNDISO 07539-003 ADuM5000 TOP VIEW (Not to Scale) 14 13 12 11 10 9 VISO Figure 3. Pin Configuration Table 12. Pin Function Descriptions Pin No. 1, 7 Mnemonic Description VDD1 Primary Supply Voltage 3.0 V to 5.5 V. Pin 1 and Pin 7 are internally connected to each other, and it is recommended that both pins be externally connected to a common power source. 2, 8 GND1 Ground 1. Ground reference for the primary side of the converter. Pin 2 and Pin 8 are internally connected to each other, and it is recommended that both pins be connected to a common ground. 3, 11, 12, 14 NC No Internal Connection. 4 RCIN Regulation Control Input. In slave power configuration (RCSEL = low), this pin is connected to the RCOUT of a master isoPower device, or tied low to disable the converter. In master/standalone mode (RCSEL = high) this pin has no function. This pin is weakly pulled to low. In noisy environments, it should be tied to low or to a PWM control source. Note: This pin must not be tied high if RCSEL is low; this combination causes excessive voltage on the secondary side of the converter, damaging the ADuM5000 and possibly the devices that it powers. 5 RCOUT Regulation Control Output. In master power configuration, this pin is connected to the RCIN of a slave isoPower device to allow the ADuM5000 to regulate additional devices. 6 RCSEL Control Input. Sets either self-regulation/master mode (RCSEL high) or slave mode (RCSEL low). This pin is weakly pulled to the high state. In noisy environments, tie this pin either high or low. 9, 15 GNDISO Ground Reference for the Secondary Side of the Converter. Pin 9 and Pin 15 are internally connected to each other, and it is recommended that both pins be connected to a common ground. 10, 16 VISO Secondary Supply Voltage Output External Loads, 3.3 V (VSEL low) or 5.0 V (VSEL high). 5.0 V output functionality is not guaranteed for a 3.3 V primary supply input. Pin 10 and Pin 16 are internally connected to each other, and connecting both to GNDISO is recommended. 13 VSEL Output Voltage Selection. When VSEL = VISO, the VISO set point is 5.0 V. When VSEL = GNDISO, the VISO set point is 3.3 V. This pin is weakly pulled to high. In noisy environments, tie this pin either high or low. In slave regulation mode, this pin has no function. Table 13. Truth Table (Positive Logic) RCSEL Input H H H H L L L RCIN Input X X X X PWM1 L H RCOUT Output PWM 1 PWM1 PWM1 PWM1 RCIN L H VSEL Input H L H L X L X VDDI Input 5.0 V 5.0 V 3.3 V 3.3 V X X X VISO Output 5.0 V 3.3 V 5.0 V 3.3 V X X X Operation Master mode operation, self regulating. Master mode operation, self regulating. This configuration is not recommended. Master mode operation, self regulating. Slave mode operation, regulation from another isoPower part. Low power mode, converter disabled. Note: This combination of RCIN and RCSEL is prohibited. Damage occurs on the secondary side of the converter due to excess output voltage at VISO. RCIN must be either low or a PWM signal from a master isoPower part. 1 PWM refers to the regulation control signal. This signal is derived from the secondary side regulator or from the RCIN input, depending on the value of RCSEL. Rev. 0 | Page 9 of 16 ADuM5000 TYPICAL PERFORMANCE CHARACTERISTICS 40 35 30 IDD1 (A) AND POWER DISSIPATION (W) 3.5 3.0 2.5 POWER EFFICIENCY (%) 25 20 15 10 5 0 07539-004 2.0 1.5 1.0 IDD 5V IN/5V OUT 3.3V IN/3.3V OUT 5V IN/3.3V OUT 0.5 0 0.02 0.04 0.06 0.08 0.10 0 3.0 3.5 4.0 OUTPUT CURRENT (A) 4.5 VDD1 (V) 5.0 5.5 6.0 Figure 4. Typical Power Supply Efficiency in All Supported Power Configurations 0.12 Figure 7. Typical Short-Circuit Input Current and Power vs. VDD1 Supply Voltage OUTPUT VOLTAGE (500mV/DIV) 0.10 OUTPUT CURRENT (A) 0.08 0.06 5V IN/5V OUT 3.3V IN/3.3V OUT 5V IN/3.3V OUT 90% LOAD 0.04 10% LOAD (100µs/DIV) 0 0 0.05 0.10 0.15 0.20 INPUT CURRENT (A) 0.25 0.30 Figure 5. Typical Isolated Output Supply Current vs. External Load in All Supported Power Configurations 1.0 0.9 0.8 07539-005 Figure 8. Typical VISO Transient Load Response, 5 V Output, 10% to 90% Load Step OUTPUT VOLTAGE (500mV/DIV) POWER DISSIPATION (W) 0.7 0.6 0.5 0.4 0.3 0.2 0.1 07539-122 0 0 0.02 0.04 IISO (A) 0.06 0.08 0.10 (100µs/DIV) Figure 6. Typical Total Power Dissipation vs. IISO in All Supported Power Configurations Figure 9. Typical Transient Load Response, 3 V Output, 10% to 90% Load Step Rev. 0 | Page 10 of 16 07539-008 5V IN/5V OUT 3.3V IN/3.3V OUT 5V IN/3.3V OUT DYNAMIC LOAD 90% LOAD 10% LOAD 07539-007 0.02 DYNAMIC LOAD 07539-006 ADuM5000 –40 BW = 20MHz –50 –30 –20 BW = 20MHz –60 RIPPLE, VISO = 3.3V (mV) 07539-009 RIPPLE, VISO = 5V (mV) –40 –70 –50 –80 –60 –90 –70 07539-010 –100 0 0.5 1.0 1.5 2.0 2.5 TIME (µs) 3.0 3.5 –80 0 0.5 1.0 1.5 2.0 2.5 TIME (µs) 3.0 3.5 4.0 4.0 Figure 10. Typical VISO = 5 V, Output Voltage Ripple at 90% Load Figure 11. Typical VISO = 3.3 V, Output Voltage Ripple at 90% Load Rev. 0 | Page 11 of 16 ADuM5000 APPLICATIONS INFORMATION The dc-to-dc converter section of the ADuM5000 works on principles that are common to most switching power supplies. It is a secondary side controller architecture with isolated pulsewidth modulation (PWM) feedback. VDD1 power is supplied to an oscillating circuit that switches current into a chip-scale air core transformer. Power transferred to the secondary side is rectified and regulated to either 3.3 V or 5 V. The secondary (VISO) side controller regulates the output by creating a PWM control signal that is sent to the primary (VDD1) side by a dedicated iCoupler data channel. The PWM modulates the oscillator circuit to control the power being sent to the secondary side. Feedback allows for significantly higher power and efficiency. The ADuM5000 provides a regulation control output (RCOUT) signal that can be connected to other isoPower devices. This feature allows a single regulator to control multiple power modules without contention. When auxiliary power modules are present, the VISO pins can be connected together to work as a single supply. Because there is only one feedback control path, the supplies work together seamlessly. The ADuM5000 can be a source of regulation control, as well as a being controlled by another isoPower device. There is an undervoltage lockout with hysteresis in the VDD1 input protection circuit. When the input voltage rises above the lockout threshold, the dc-to-dc converter becomes active. The input voltage must be decreased below the turn-on threshold by the hysteresis value to disable the converter. This feature has many benefits in the power-up sequence of the converter, such as it ensures that the system supply rises to a minimum level before the ADuM5000 demands current. It also prevents any voltage drop due to converter current from turning the supply off and possibly oscillating. 10 mm. Consider bypassing between Pin 1 and Pin 8 and between Pin 9 and Pin 16 unless both of the common ground pins are connected together close to the package. VDD1 GND1 NC RCIN RCOUT RCSEL VDD1 GND1 NC NC GNDISO 07539-011 VISO GNDISO NC VSEL VISO Figure 12. Recommended PCB Layout In applications involving high common-mode transients, ensure that board coupling across the isolation barrier is minimized. Furthermore, design the board layout such that any coupling that does occur equally affects all pins on a given component side. Failure to ensure this can cause voltage differentials between pins exceeding the absolute maximum ratings for the device as specified in Table 10, thereby leading to latch-up and/or permanent damage. The ADuM5000 is a power device that dissipates about 1 W of power when fully loaded. Because it is not possible to apply a heat sink to an isolation device, the device primarily depends on heat dissipation into the PCB through the GND pins. If the device is used at high ambient temperatures, provide a thermal path from the GND pins to the PCB ground plane. The board layout in Figure 12 shows enlarged pads for Pin 2, Pin 8, Pin 9, and Pin 15. Implement multiple vias from the pad to the ground plane to significantly reduce the temperature inside the chip. The dimensions of the expanded pads are at the discretion of the designer and dependent on the available board space. EMI CONSIDERATIONS It is necessary for the dc-to-dc converter section of the ADuM5000 to operate at 180 MHz to allow efficient power transfer through the small transformers. This creates high frequency currents that can propagate in circuit board ground and power planes, causing edge emissions and dipole radiation between the input and output ground planes. Grounded enclosures are recommended for applications that use these devices. If grounded enclosures are not possible, follow good RF design practices in the layout of the PCB. See www.analog.com for the most current PCB layout recommendations specifically for the ADuM5000. PCB LAYOUT The ADuM5000 digital isolator is a 0.5 W isoPower integrated dc-to-dc converter requiring no external interface circuitry for the logic interfaces. Power supply bypassing is required at the input and output supply pins (see Figure 12). The power supply section of the ADuM5000 uses a 180 MHz oscillator frequency to pass power efficiently through its chip scale transformers. In addition, the normal operation of the data section of the iCoupler introduces switching transients on the power supply pins. Bypass capacitors are required for several operating frequencies. Noise suppression requires a low inductance, high frequency capacitor, whereas ripple suppression and proper regulation require a large value capacitor. These are most conveniently connected between Pin 1 and Pin 2 for VDD1, and between Pin 15 and Pin 16 for VISO. To suppress noise and reduce ripple, a parallel combination of at least two capacitors is required. The recommended capacitor values are 0.1 μF, and 10 μF. Best practice recommends using a very low inductance ceramic capacitor, or its equivalent, for the smaller value. The total lead length between both ends of the capacitor and the input power supply pin should not exceed THERMAL ANALYSIS The ADuM5000 consists of four internal silicon die, attached to a split lead frame with two die attach paddles. For the purposes of thermal analysis, it is treated as a thermal unit with the highest junction temperature reflected in the θJA from Table 5. The value of θJA is based on measurements taken with the part mounted on a JEDEC standard 4-layer board with fine width traces and still air. Under normal operating conditions, the ADuM5000 operates at full load across the full temperature range without Rev. 0 | Page 12 of 16 ADuM5000 derating the output current. However, following the recommendations in the PCB Layout section decreases the thermal resistance to the PCB allowing increased thermal margin at high ambient temperatures. ondary voltage rises to its regulation setpoint, a large inrush current transient is present at VDD1. When the regulation point is reached, the regulation control circuit produces the regulation control signal that modulates the oscillator on the primary side. The VDD1 current is then reduced and is proportional to the load current. The inrush current is less than the short-circuit current shown in Figure 7. The duration of the inrush depends on the VISO loading conditions and the current and voltage available at the VDD1 pin. CURRENT LIMIT AND THERMAL OVERLOAD PROTECTION The ADuM5000 is protected against damage due to excessive power dissipation by thermal overload protection circuits. Thermal overload protection limits the junction temperature to a maximum of 150°C (typical). Under extreme conditions (that is, high ambient temperature and power dissipation), when the junction temperature starts to rise above 150°C, the PWM is turned off, reducing the output current to zero. When the junction temperature drops below 130°C (typical), the PWM turns on again, restoring the output current to its nominal value. Consider the case where a hard short from VISO to ground occurs. At first, the ADuM5000 reaches its maximum current, which is proportional to the voltage applied at VDD1. Power dissipates on the primary side of the converter (see Figure 7). If self-heating of the junction becomes great enough to cause its temperature to rise above 150°C, thermal shutdown activates, turning off the PWM and reducing the output current to zero. As the junction temperature cools and drops below 130°C, the PWM turns on and power dissipates again on the primary side of the converter, causing the junction temperature to rise to 150°C again. This thermal oscillation between 130°C and 150°C causes the part to cycle on and off as long as the short remains at the output. Thermal limit protections are intended to protect the device against accidental overload conditions. For reliable operation, externally limit device power dissipation to prevent junction temperatures from exceeding 130°C. INCREASING AVAILABLE POWER The ADuM5000 device is designed with the capability of running in combination with other compatible isoPower devices. The RCOUT, RCIN, and RCSEL pins allow the ADuM5000 to provide its PWM signal to another device through the RCOUT pin acting as a master. It can also receive a PWM signal from another device through the RCIN pin and act as a slave to that control signal. The RCSEL pin chooses whether the part acts as a master or slave device. When the ADuM5000 is acting as a slave, its power is regulated by the master device allowing multiple isoPower parts to be combined in parallel while sharing the load equally. When the ADuM5000 is configured as a master/ standalone unit, it generates its own PWM feedback signal to regulate itself and slave devices. The ADuM5000 can act as a master or a slave device, the ADuM5401 through the ADuM5404 devices can only serve as master/standalone, and the ADuM520x can only be a slave/standalone device. This means that the ADuM5000, ADuM520x, and ADuM5401, ADuM5402, ADuM5403, and ADuM5404 can only be used in certain master slave combinations as listed in Table 14. Table 14. Allowed Combinations of isoPower Parts Slave Master ADuM5000 ADuM520x ADuM5401 to ADuM5404 ADuM5000 Yes No Yes ADuM520x Yes No Yes ADuM5401 to ADuM5404 No No No POWER CONSIDERATIONS The ADuM5000 converter primary side is protected from premature operation by undervoltage lockout (UVLO) circuitry. Below the minimum operating voltage, the power converter holds its oscillator inactive. When the primary side oscillator begins to operate, it transfers power to the secondary power circuits. The secondary VISO voltage starts below its UVLO limit making it inactive and unable to generate a regulation control signal. The primary side power oscillator is allowed to free run under this condition, supplying the maximum amount of power to the secondary. As the sec- The allowed combinations of master and slave configured parts listed in Table 14 is sufficient for any combination of power and channel count. Table 15 illustrates how isoPower devices can provide many combinations of data channel count and multiples of the single unit power. Rev. 0 | Page 13 of 16 ADuM5000 Table 15. Configurations for Power and Data Channels Power Units 1-Unit Power 2-Unit Power 3-Unit Power 0 ADuM5000 master ADuM5000 master ADuM5000 slave ADuM5000 master ADuM5000 slave ADuM5000 slave 2 ADuM520x master ADuM5000 master ADuM520x slave ADuM5000 master ADuM5000 slave ADuM520x slave Number of Data Channels 4 ADuM5401 to ADuM5404 master ADuM5401 to ADuM5404master ADuM520x slave ADuM5401 to ADuM5404 master ADuM5000 slave ADuM5000 slave 6 ADuM5401 to ADuM5404 master ADuM121x ADuM5401 to ADuM5404 master ADuM520x slave ADuM5401 to ADuM5404master ADuM520x slave ADuM5000 slave Another feature that is allowed by the RCSEL and RCIN control architecture is the ability to completely shut down the oscillator in the dc-to-dc converter. This places the part in a low power standby mode and reduces the current draw to a fraction of a milliamp. When the ADuM5000 is placed in slave mode by driving RCSEL low, the oscillator is controlled by RCIN. If RCIN is held low, the oscillator is shut down and the part is in low power standby. With no oscillator driving power to the secondary, VISO turns off. This mode is useful for applications where an isolated subsystem may be shut down to conserve power. To reactivate the power module, simply drive RCSEL high and the power supply resumes operation. Bipolar ac voltage is the most stringent environment. The goal of a 50-year operating lifetime under the ac bipolar condition determines the maximum working voltage that Analog Devices recommends. In the case of unipolar ac or dc voltage, the stress on the insulation is significantly lower. This allows operation at higher working voltages while still achieving a 50-year service life. The working voltages listed in Table 11 can be applied while maintaining the 50-year minimum lifetime, provided the voltage conforms to either the unipolar ac or dc voltage cases. Treat any cross insulation voltage waveform that does not conform to Figure 14 or Figure 15 as a bipolar ac waveform and limit its peak voltage to the 50-year lifetime voltage value listed in Table 11. The voltage presented in Figure 14 is shown as sinusoidal for illustration purposes only. It is meant to represent any voltage waveform varying between 0 V and some limiting value. The limiting value can be positive or negative, but the voltage cannot cross 0 V. RATED PEAK VOLTAGE 0V 07539-021 INSULATION LIFETIME All insulation structures eventually break down when subjected to voltage stress over a sufficiently long period. The rate of insulation degradation is dependent on the characteristics of the voltage waveform applied across the insulation. In addition to the testing performed by the regulatory agencies, Analog Devices carries out an extensive set of evaluations to determine the lifetime of the insulation structure within the ADuM5000. Analog Devices performs accelerated life testing using voltage levels higher than the rated continuous working voltage. Acceleration factors for several operating conditions are determined. These factors allow calculation of the time to failure at the actual working voltage. The values shown in Table 11 summarize the peak voltage for 50 years of service life for a bipolar ac operating condition, and the maximum CSA/VDE approved working voltages. In many cases, the approved working voltage is higher than 50-year service life voltage. Operation at these high working voltages can lead to shortened insulation life in some cases. The insulation lifetime of the ADuM5000 depends on the voltage waveform imposed across the isolation barrier. The iCoupler insulation structure degrades at different rates depending on whether the waveform is bipolar ac, unipolar ac, or dc. Figure 13, Figure 14, and Figure 15 illustrate these different isolation voltage waveforms. Figure 13. Bipolar AC Waveform RATED PEAK VOLTAGE 07539-022 0V Figure 14. Unipolar AC Waveform RATED PEAK VOLTAGE 07539-023 0V Figure 15. DC Waveform Rev. 0 | Page 14 of 16 ADuM5000 OUTLINE DIMENSIONS 10.50 (0.4134) 10.10 (0.3976) 16 9 7.60 (0.2992) 7.40 (0.2913) 1 8 10.65 (0.4193) 10.00 (0.3937) 1.27 (0.0500) BSC 0.30 (0.0118) 0.10 (0.0039) COPLANARITY 0.10 0.51 (0.0201) 0.31 (0.0122) 2.65 (0.1043) 2.35 (0.0925) 0.75 (0.0295) 0.25 (0.0098) 8° 0° 0.33 (0.0130) 0.20 (0.0079) 45° SEATING PLANE 1.27 (0.0500) 0.40 (0.0157) COMPLIANT TO JEDEC STANDARDS MS-013- AA CONTROLLING DIMENSIONS ARE IN MILLIMETERS; INCH DIMENSIONS (IN PARENTHESES) ARE ROUNDED-OFF MILLIMETER EQUIVALENTS FOR REFERENCE ONLY AND ARE NOT APPROPRIATE FOR USE IN DESIGN. Figure 16. 16-Lead Standard Small Outline Package [SOIC_W] Wide Body (RW-16) Dimensions shown in millimeters and (inches) ORDERING GUIDE Model ADuM5000ARWZ 1, 2 1 2 Temperature Range −40°C to +105°C Package Description 16-Lead SOIC_W Package Option RW-16 Z = RoHS Compliant Part. Tape and reel are available. The additional -RL suffix designates a 13-inch (1,000 units) tape and reel option. Rev. 0 | Page 15 of 16 032707-B ADuM5000 NOTES ©2008 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D07539-0-10/08(0) Rev. 0 | Page 16 of 16