FAN6206 Highly Integrated Dual-Channel Synchronous Rectification Controller for Dual-Forward Converter Features Description Highly Integrated Dual-Channel SR Controller Internal Linear-Predict Timing Control for DCM Operation The highly integrated FAN6206 is a dual-channel synchronous rectification (SR) controller. FAN6206 allows design of a cost-effective power supply with fewer external components, especially suited for dualforward topology used to obtain higher efficiency for ATX power supplies. Ultra-Low VDD Operating Voltage for Different Output Voltage of PC Power VDD Over-Voltage Protection Receives Synchronized Driving Signal from the Primary Side 14V Gate Driver Clamp Applications PC Power Server Power Open-Frame SMPS The primary-side control method provides synchronous rectification control for dual-forward converters that operate in continuous conduction mode (CCM). FAN6206 includes a proprietary linear-predict timing control mechanism for dual-forward converters that operate in discontinuous conduction mode (DCM) at fixed or variable frequency. PWM frequency tracking with secondary-side winding detection is provided by adding dividing resistors. The primary-side signals are generated from Fairchild’s FAN6210 (Primary-Side Synchronous Rectifier Signal Trigger for Dual-Forward Converter). The primary-side signals are transferred through a pulse transformer to the secondary-side. The benefits of this technique include simple control method and improved power system reliability. FAN6206 is available in 8-pin SOP package. Ordering Information Part Number Operating Temperature Range Package Packing Method FAN6206MY -40°C to +105°C 8-Pin Small Outline Package (SOP) Tape & Reel © 2010 Fairchild Semiconductor Corporation FAN6206 • Rev. 1.0.2 www.fairchildsemi.com FAN6206 —Highly Integrated Dual-Channel Synchronous Rectification Controller for Dual-Forward Converter April 2010 Figure 1. Typical Application Internal Block Diagram FAN6206 — Highly Integrated Dual-Channel Synchronous Rectification Controller for Dual-Forward Converter Application Diagram Figure 2. Functional Block Diagram © 2010 Fairchild Semiconductor Corporation FAN6206 • Rev. 1.0.2 www.fairchildsemi.com 2 F: Fairchild Logo Z: Plant Code X: Year Code Y: Week Code TT: Package Type T: M=SOP P: Y: Green Package M: Manufacture Flow Code Figure 3. Top Mark Pin Configuration Figure 4. Pin Configuration Pin Definitions Pin # Name Description 1,2 LPC1, LPC2 3 SN Synchronized signal to turn on SR. This pin is used to receive the “XN” signal from the primary side to turn off the SR gate. 4 SP Synchronized signal to turn on SR. This pin is used to receive the “XP” signal from the primaryside to turn-on the SR gate. 5 VDD 6 GATE2 7 GND 8 GATE1 Winding detection. This pin is used to detect the voltage on the winding during the on-time period of the primary GATE. An internal current source, ICHG, is determined according to the voltage on the DET pin. Power supply pin. The threshold voltages for startup and turn-off are 8.5V and 7.5V, respectively. Driver output for freewheeling synchronous rectifier MOSFET. Ground Driver output for rectifying synchronous rectifier MOSFET. © 2010 Fairchild Semiconductor Corporation FAN6206 • Rev. 1.0.2 FAN6206 — Highly Integrated Dual-Channel Synchronous Rectification Controller for Dual-Forward Converter Marking Information www.fairchildsemi.com 3 Stresses exceeding the absolute maximum ratings may damage the device. The device may not function or be operable above the recommended operating conditions and stressing the parts to these levels is not recommended. In addition, extended exposure to stresses above the recommended operating conditions may affect device reliability. The absolute maximum ratings are stress ratings only. Symbol Parameter Min. Max. Unit VDD DC Supply Voltage 30 V VHV SP, SN 30 V VL LPC 7.0 V PD Power Dissipation at TA < 50°C 400 mW ΘJA Junction to Ambient Thermal Resistance 130 °C/W Ψjt Junction to Top Thermal Characteristics 46 °C/W TJ Operating Junction Temperature -40 +125 °C Storage Temperature Range -55 +150 °C °C TSTG TL ESD -0.3 Lead Temperature, (Soldering 10 Seconds) +260 Human Body Model, JESD22-A114 4.00 Charged Device Model, JESD22-C101 1.25 kV Notes: 1. Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. 2. All voltage values, except differential voltages, are given with respect to GND pin. Recommended Operating Conditions The Recommended Operating Conditions table defines the conditions for actual device operation. Recommended operating conditions are specified to ensure optimal performance to the datasheet specifications. Fairchild does not recommend exceeding them or designing to Absolute Maximum Ratings. Symbol TA Parameter Operating Ambient Temperature © 2010 Fairchild Semiconductor Corporation FAN6206 • Rev. 1.0.2 Min. Max. Unit -40 +105 °C FAN6206 — Highly Integrated Dual-Channel Synchronous Rectification Controller for Dual-Forward Converter Absolute Maximum Ratings www.fairchildsemi.com 4 VDD=20V, TA=25Ԩ, unless otherwise specified. Symbol Parameter Conditions Min. Typ. Max. Units 25 V VDD Section VOP VTH-ON1 Continuously Operating Voltage Turn-On Threshold Voltage 8.0 8.5 9.0 V VTH-ON2 Turn-On Threshold Voltage 8.0 8.5 9.0 V VTH-OFF1 Turn-Off Threshold Voltage 7.0 7.5 8.0 V VTH-OFF2 Turn-Off Threshold Voltage 7.0 7.5 8.0 V 3 5 mA IDD-OP Operating Current VDD=15V, DET=50KHz IDD-ST Startup Current VDD = 7.5V 340 500 μA VDD-OVP1 VDD Over-Voltage Protection 1 20 21 22 V VDD-OVP2 VDD Over-Voltage Protection 2 20 21 22 V VDD-OVP-HYS1 Hysteresis Voltage for VDD OVP 1 1.2 1.7 2.2 V VDD-OVP-HYS2 Hysteresis Voltage for VDD OVP 2 1.2 1.7 2.2 V tOVP1 VDD OVP Debounce Time 1 40 60 100 μs tOVP2 VDD OVP Debounce Time 2 40 60 100 μs Output Drive for SR MOSFET Section VZ1 Output Voltage Maximum (Clamp) 1 VDD = 20V 12 14 V VZ2 Output Voltage Maximum (Clamp) 2 VDD = 20V 12 14 V VOL1 Output Voltage LOW 1 VDD=12V, IO=50mA 0.5 V 0.5 V VOL2 Output Voltage LOW 2 VDD=12V, IO=50mA VOH1 Output Voltage HIGH 1 VDD=12V, IO=50mA 9 V VOH2 Output Voltage HIGH 2 VDD=12V, IO=50mA 9 V tR1 Rising Time 1 VDD=12V, CL=7nF, OUT=2V~9V 30 70 120 ns tR2 Rising Time 2 VDD=12V, CL=7nF, OUT=2V~9V 30 70 120 ns tF1 Falling Time1 VDD=12V, CL=7nF, OUT=9V~2V 20 50 100 ns tF2 Falling Time 2 VDD=12V, CL=7nF, OUT=9V~2V 20 50 100 ns VZ1 Output Voltage Maximum (Clamp) VDD = 20V 12 14 V tR+tPD, (Trigger by SP), |SP-SN|=5V 280 350 450 Propagation Delay to OUT HIGH 280 350 450 tR+tPD, (Trigger by SN), |SP-SN|=5V 180 250 350 Propagation Delay to OUT LOW 180 250 350 Propagation Delay to OUT LOW tR+tPD, (Trigger by LPC) 100 150 200 100 150 200 12 13 14 μs 12 13 14 μs tPD-HIGH-SP1 tPD-HIGH-SP2 tPD-LOW-SN1 tPD-LOW-SN2 tPD-LOW-LPC1 tPD-LOW-LPC2 tON-MAX1 tON-MAX2 Maximum On Time ns ns ns FAN6206 — Highly Integrated Dual-Channel Synchronous Rectification Controller for Dual-Forward Converter Electrical Characteristics Continued on the following page… © 2010 Fairchild Semiconductor Corporation FAN6206 • Rev. 1.0.2 www.fairchildsemi.com 5 VDD=20V, TA=25°C, unless otherwise specified. Symbol Parameter Conditions Min. Typ. Max. Units Sweep VN-P- from LOW to HIGH 3 4 5 V 3 4 5 V SP/SN Section VN-P(turn off) 1 Threshold Voltage of VN-VP to Turn-Off SR MOS 1 VN-P(turn off) 2 Threshold Voltage of VN-VP to Turn-Off SR MOS 2 VP-N(turn on) 1 Threshold Voltage of VP-VN to Turn-On SR MOS 1 Sweep VP-N- from LOW to HIGH 3 4 5 V VP-N(turn on) 2 Threshold Voltage of VP-VN to Turn-On SR MOS 2 Sweep VP-N- from LOW to HIGH 3 4 5 V Ratio_SP-SN Voltage Difference between SP and SN | VSP-VSN | / MIN(VSP,VSN) 5 % Ratio_LPC-RES Charge Divide Discharge Current Transfer Ratio vs. Input Voltage Connect a Diode 1N4148 and Divider (Ratio 12) to LPC, VDET = 3V, VLPC = 3V VLPC-EN1 VLPC-EN2 LPC Section 2.79 3.00 3.21 LPC Enable Threshold Voltage 1 1.8 2.0 2.2 V LPC Enable Threshold Voltage 2 1.8 2.0 2.2 V VLPC-CLAMP1 Lower Clamp Voltage 1 ILPC = -5μA 0.10 0.25 0.40 V VLPC-CLAMP2 Lower Clamp Voltage 2 ILPC = -5μA 0.10 0.25 0.40 V ILPC-SOURCE1 Maximum Source Current 1 VLPC = -0.3V 250 300 μA ILPC-SOURCE2 Maximum Source Current 2 VLPC = -0.3V 250 300 μA VLPC-LOW1 Threshold Voltage for Disable LPC Function 1.3 1.5 1.7 V VLPC-LOW2 Threshold Voltage for Disable LPC Function 1.3 1.5 1.7 V tLPC-LOW1 Debounce Time for Disable LPC Function VLPC < VLPC-LOW 70 100 130 μs tLPC-LOW2 Debounce Time for Disable LPC Function VLPC < VLPC-LOW 70 100 130 μs © 2010 Fairchild Semiconductor Corporation FAN6206 • Rev. 1.0.2 FAN6206 — Highly Integrated Dual-Channel Synchronous Rectification Controller for Dual-Forward Converter Electrical Characteristics www.fairchildsemi.com 6 8.5 8.5 8.4 8.4 VTH-ON2 (V) VTH-ON1 (V) These characteristic graphs are normalized at TA = 25°C. 8.3 8.2 8.1 8.2 8.1 8.0 8.0 -40 -25 -10 5 20 35 50 65 80 95 110 125 -40 -25 -10 5 20 35 50 65 80 95 110 125 Temperature℃ Temperature℃ Figure 5. Turn-On Threshold Voltage 1 Figure 6. Turn-On Threshold Voltage 2 7.7 7.7 7.6 7.6 VTH-OFF2 (V) VTH-OFF1 (V) 8.3 7.5 7.4 7.5 7.4 7.3 7.3 -40 -25 -10 5 20 35 50 65 80 95 110 125 -40 -25 -10 5 20 35 50 65 80 95 110 125 Temperature℃ Temperature℃ Figure 7. Turn-Off Threshold Voltage 1 Figure 8. Turn-Off Threshold Voltage 2 2.9 500 IDD_ST (uA) IDD_OP (mA) 2.8 2.7 400 300 2.6 2.5 200 -40 -25 -10 5 20 35 50 65 80 95 110 125 -40 -25 -10 5 Temperature℃ 35 50 65 80 95 110 125 110 125 Temperature℃ Figure 9. Operating Current Figure 10.Startup Current 420 420 400 400 tPD-HIGH-SP2 (ns) tPD-HIGH-SP1 (ns) 20 380 360 340 320 300 380 360 340 320 300 280 280 -40 -25 -10 5 20 35 50 65 80 95 110 125 -40 Temperature℃ -10 5 20 35 50 65 80 95 Temperature℃ Figure 11. Propagation Delay to OUT HIGH 1 (Trigger by SP) © 2010 Fairchild Semiconductor Corporation FAN6206 • Rev. 1.0.2 -25 FAN6206 — Highly Integrated Dual-Channel Synchronous Rectification Controller for Dual-Forward Converter Typical Performance Characteristics Figure 12.Propagation Delay to OUT HIGH 2 (Trigger by SP) www.fairchildsemi.com 7 350 350 300 300 tPD-LOW-SN2 (ns) tPD-LOW-SN1 (ns) These characteristic graphs are normalized at TA = 25°C. 250 200 150 250 200 150 -40 -25 -10 5 20 35 50 65 80 95 110 125 -40 -25 -10 5 Temperature℃ 35 50 65 80 95 110 125 Temperature℃ Figure 13. Propagation Delay to OUT LOW 1 (Trigger by SN) Figure 14.Propagation Delay to OUT LOW 2 (Trigger by SN) 180 tPD-LOW-LPC2 (ns) 180 tPD-LOW-LPC1 (ns) 20 160 140 120 160 140 120 -40 -25 -10 5 20 35 50 65 80 95 110 125 -40 -25 -10 5 20 35 50 65 80 95 110 125 Temperature℃ Figure 15. Propagation Delay to OUT LOW 1 (Trigger by LPC) Figure 16.Propagation Delay to OUT LOW 2 (Trigger by LPC) 14.0 14.0 13.5 13.5 tON-MAX2 (us) tON_MAX1 (us) Temperature℃ 13.0 12.5 13.0 12.5 12.0 12.0 -40 -25 -10 5 20 35 50 65 80 95 110 125 -40 -25 -10 5 Temperature℃ 35 50 65 80 95 110 125 Temperature℃ Figure 17. Maximum On Time 1 Figure 18.Maximum On Time 2 5.0 5.0 4.5 4.5 VN-P(turn off) 2 (V) VN-P(turn off) 1 (V) 20 4.0 3.5 3.0 4.0 3.5 3.0 -40 -25 -10 5 20 35 50 65 80 95 110 125 -40 -25 -10 5 20 35 50 65 80 95 110 125 Temperature℃ Temperature℃ Figure 19. Threshold Voltage of VN-VP to Turn Off SR MOS 1 Figure 20.Threshold Voltage of VN-VP to Turn Off SR MOS 2 © 2010 Fairchild Semiconductor Corporation FAN6206 • Rev. 1.0.2 FAN6206 — Highly Integrated Dual-Channel Synchronous Rectification Controller for Dual-Forward Converter Typical Performance Characteristics www.fairchildsemi.com 8 5.0 5.0 4.5 4.5 VP-N(turn on) 2 (ns) VP-N(turn on) 1 (V) These characteristic graphs are normalized at TA = 25°C. 4.0 3.5 3.0 3.5 3.0 -40 -25 -10 5 20 35 50 65 80 95 110 125 -40 -25 -10 5 20 35 50 65 80 95 110 125 Temperature℃ Temperature℃ Figure 21. Threshold Voltage of VP-VN to Turn On SR MOS 1 Figure 22.Threshold Voltage of VP-VN to Turn On SR MOS 2 2.2 2.2 2.1 2.1 VLPC-EN2 (V) VLPC-EN1 (V) 4.0 2.0 1.9 2.0 1.9 1.8 1.8 -40 -25 -10 5 20 35 50 65 80 95 110 125 -40 -25 -10 5 20 35 50 65 80 95 110 125 Temperature℃ Temperature℃ Figure 23. LPC Enable Threshold Voltage 1 Figure 24.LPC Enable Threshold Voltage 2 0.4 VLPC-CLAMP2 (V) VLPC-CLAMP1 (V) 0.4 0.3 0.2 0.1 0.2 0.1 -40 -25 -10 5 20 35 50 65 80 95 110 125 -40 -25 -10 5 20 35 50 65 80 95 110 125 Temperature℃ Temperature℃ Figure 25. Lower Clamp Voltage 1 Figure 26.Lower Clamp Voltage 2 300 300 275 275 ILPC-SOURCE2 (V) ILPC-SOURCE1 (uA) 0.3 250 225 200 250 225 200 -40 -25 -10 5 20 35 50 65 80 95 110 125 -40 Temperature℃ -10 5 20 35 50 65 80 95 110 125 Temperature℃ Figure 27. Maximum Source Current 1 © 2010 Fairchild Semiconductor Corporation FAN6206 • Rev. 1.0.2 -25 Figure 28.Maximum Source Current 2 FAN6206 — Highly Integrated Dual-Channel Synchronous Rectification Controller for Dual-Forward Converter Typical Performance Characteristics www.fairchildsemi.com 9 Figure 31 shows a typical application circuit. When a dual-forward converter operates in continuous conduction mode, the SR gate signals (GATE1 and GATE2) are mainly controlled by SP and SN signals. SP and SN signals are transferred through a pulse transformer from XP and XN signals, which are generated by FAN6210 (Primary-Side Synchronous Rectifier Signal Trigger for Dual Forward Converter). Figure 29 and Figure 30 show the simplified circuit diagram of a dual-forward converter and its key waveforms. Switches Q1 and Q2 are turned on and off together. Once Q1 and Q2 are turned on, input voltage is applied across the transformer primary side and power is delivered to the secondary side through the transformer, powering D1. During this time, the magnetizing current linearly increases. When Q1 and Q2 are turned off, the magnetizing current of the transformer forces the reset diodes (DR1 and DR2) and negative input voltage is applied across the transformer primary side. During this time, magnetizing current linearly decreases to zero and the secondary-side inductor current freewheels through diode D2. When synchronous rectifier SR1 and SR2 are used instead of diodes D1 and D2, it is important to have proper timing between drive signals for SR1 and SR2. Figure 31. Typical Application Circuit Figure 32 shows the timing diagram for continuous conduction mode (CCM). Figure 33 shows the timing diagram for discontinuous conduction mode (DCM). The switching operation of SR MOSFETs Q3 and Q4 is determined by the SN and SP signals. FAN6206 turns on SR MOSFETs at the rising edge of the SP signal, while it turns off the SR MOSFETs at the rising edge of the SN signal. Within one switching cycle, SP and SN are obtained two times. Figure 29. Simplified Circuit Diagram of Dual-Forward Converter With a voltage divider R1 and R2 connected from LPC1 to secondary winding, R3 and R4 connected from LPC2 to secondary winding, the PWM timing sequences and frequency can be tracked precisely. The SR MOSFET is turned on by SP signal only when the voltage level on LPC1 or LPC2 pin is pulled LOW to GND. During PWM-on period, the rectifying SR Q3 is turned on by the rising edge of the SP signal after a propagation delay (tPD-HIGH-SP1) and Q3 is turned off by the rising edge of the SN signal after a propagation delay (tPD-LOW-SN1). During PWM-off period, the freewheeling SR Q4 is turned on by the rising edge of the SP signal after a propagation delay (tPD-HIGH-SP2) and Q4 is turned off by the rising edge of the SN signal after a propagation delay (tPD-LOW-SN2) in CCM operation. In DCM operation, the proprietary Linear-Predict Timing Control (LPC) technique can provide synchronous rectification control mechanism for freewheeling SR MOSFET. Since SN signal is sent following with PWM signal, the freewheeling SR MOSFET cannot be turned off in time by SN signal before ILo linearly decreases to zero. Therefore, the LPC mechanism is applied to turn off Q3 in DCM mode. Figure 30. Key Waveforms of Dual-Forward Converter © 2010 Fairchild Semiconductor Corporation FAN6206 • Rev. 1.0.2 FAN6206 — Highly Integrated Dual-Channel Synchronous Rectification Controller for Dual-Forward Converter Function Description www.fairchildsemi.com 10 FAN6206 — Highly Integrated Dual-Channel Synchronous Rectification Controller for Dual-Forward Converter Figure 32. SR Gate is Driven by SP & SN Signal in CCM Mode Figure 33. Freewheeling SR Turned Off by LPC Mechanism in DCM Mode © 2010 Fairchild Semiconductor Corporation FAN6206 • Rev. 1.0.2 www.fairchildsemi.com 11 Under-Voltage Lockout (UVLO) When a dual-forward converter operates in CCM or DCM; in PWM tON period, the VIN voltage is applied to the primary winding and the secondary inductor starts to rise linearly and store energy. The across voltage on secondary winding is coupled from primary winding and proportional to VIN. The SR controller can detect this winding voltage through a voltage divider and acquire the VIN level. According to this detected VIN level during PWM turn-on period, SR controller produces a charge current ICHG to charge internal capacitor, CT, of the SR controller. On the other hand, at PWM turn-off period, the energy stored in the secondary inductor is discharged. The SR controller also detects the output voltage level to modulate discharge current IDISCHG of internal capacitor, CT. Once the internal capacitor voltage reaches zero, SR controller turns off SR MOS immediately. The power-on and off thresholds are fixed at 8.5V and 7.5V. The VDD pin is connected to a 12V output voltage terminal. VDD Pin Over-Voltage Protection The over-voltage conditions are usually caused by open feedback loops. VDD over-voltage protection is built in to prevent damage if over voltage occurs. When the voltage on the VDD pin exceeds 21V, the SR controller turns off all of SR MOS operations. R4 is connected between the LPC2 pin and the drain terminal of Q4. During PWM turn-on period, voltage on the LPC2 pin is pulled HIGH due to the secondary winding coupled from primary winding. At this moment, SR MOS is turned off and the internal body diode of SR MOS is reverse-biased. During PWM turn-off period, the potential on the primary winding reverses and the internal body diode starts to conduct output current. The voltage on the LPC2 pin is also pulled LOW to GND. R2 is recommended as 10kΩ and the divided voltage level on the LPC1 pin is suggested between 3V~5V. If the voltage level of VO is 12V, the resistor values are recommended as 105kΩ for R3 and 10kΩ for R4. The R4 turn-off timing of Q4 is determined by the ratio R3 + R 4 as Figure 34 shows. If R4 decreases, Q4 is turned R3 + R 4 off earlier. Figure 34. Turn-Off Timing of Freewheeling SR © 2010 Fairchild Semiconductor Corporation FAN6206 • Rev. 1.0.2 FAN6206 — Highly Integrated Dual-Channel Synchronous Rectification Controller for Dual-Forward Converter Linear-Predict Timing Control www.fairchildsemi.com 12 Application Fairchild Devices Input Voltage Range Output 90~264VAC 12V/25A FAN4801 PC Power FAN6210 FAN6206 Figure 35. Application Circuit © 2010 Fairchild Semiconductor Corporation FAN6206 • Rev. 1.0.2 FAN6206 — Highly Integrated Dual-Channel Synchronous Rectification Controller for Dual-Forward Converter Typical Application Circuit (Dual-Forward Converter with SR) www.fairchildsemi.com 13 5.00 4.80 A 0.65 3.81 5 8 B 6.20 5.80 PIN ONE INDICATOR 1.75 4.00 3.80 1 5.60 4 1.27 (0.33) 0.25 M 1.27 C B A LAND PATTERN RECOMMENDATION 0.25 0.10 SEE DETAIL A 1.75 MAX 0.25 0.19 C 0.10 0.51 0.33 0.50 x 45° 0.25 R0.10 C OPTION A - BEVEL EDGE GAGE PLANE R0.10 OPTION B - NO BEVEL EDGE 0.36 NOTES: UNLESS OTHERWISE SPECIFIED 8° 0° 0.90 0.406 A) THIS PACKAGE CONFORMS TO JEDEC MS-012, VARIATION AA, ISSUE C, B) ALL DIMENSIONS ARE IN MILLIMETERS. C) DIMENSIONS DO NOT INCLUDE MOLD FLASH OR BURRS. D) LANDPATTERN STANDARD: SOIC127P600X175-8M. E) DRAWING FILENAME: M08AREV13 SEATING PLANE (1.04) DETAIL A SCALE: 2:1 Figure 36. 8-Pin Small Outline Package (SOP) Package drawings are provided as a service to customers considering Fairchild components. Drawings may change in any manner without notice. Please note the revision and/or date on the drawing and contact a Fairchild Semiconductor representative to verify or obtain the most recent revision. Package specifications do not expand the terms of Fairchild’s worldwide terms and conditions, specifically the warranty therein, which covers Fairchild products. Always visit Fairchild Semiconductor’s online packaging area for the most recent package drawings: http://www.fairchildsemi.com/packaging/. © 2010 Fairchild Semiconductor Corporation FAN6206 • Rev. 1.0.2 FAN6206 — Highly Integrated Dual-Channel Synchronous Rectification Controller for Dual-Forward Converter Physical Dimensions www.fairchildsemi.com 14 FAN6206 — Highly Integrated Dual-Channel Synchronous Rectification Controller for Dual-Forward Converter 15 www.fairchildsemi.com © 2010 Fairchild Semiconductor Corporation FAN6206 • Rev. 1.0.2