MP6910 Fast Turn-off Intelligent Rectifier The Future of Analog IC Technology DESCRIPTION FEATURES The MP6910 is a fast turn-off intelligent rectifier for Flyback converters that combines a 100V power switch that replaces diode rectifiers for high efficiency. The chip regulates the forward voltage drop of the internal power switch to about 70mV and turns it off before the voltage goes negative. • • • • • • • Supports DCM and Quasi-Resonant Flyback converter Integrated 10mΩ 100V Power Switch Compatible with Energy Star, 1W Standby Requirements VDD Range From 8V to 24V Max 400kHz Switching Frequency Supports High-side and Low-side Rectification Power Savings of Up to 1.5W in a Typical Notebook Adapter APPLICATIONS • • • • Industrial Power Systems Distributed Power Systems Battery Powered Systems Flyback Converters All MPS parts are lead-free and adhere to the RoHS directive. For MPS green status, please visit MPS website under Products, Quality Assurance page. “MPS” and “The Future of Analog IC Technology” are Registered Trademarks of Monolithic Power Systems, Inc. TYPICAL APPLICATION MP6910 MP6910 Rev. 1.04 1/3/2013 www.MonolithicPower.com MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2013 MPS. All Rights Reserved. 1 MP6910- FAST TURN-OFF INTELLIGENT RECTIFIER ORDERING INFORMATION Part Number* Package TO220-3 MP6910DZ Top Marking MP6910DZ * For RoHS Compliant Packaging, add suffix –LF; (e.g. MP6910DZ–LF) PACKAGE REFERENCE VDDVD VS ABSOLUTE MAXIMUM RATINGS (1) VDD to VS .......................................-0.3V to +27V VD to VS .......................................-0.7V to +100V Maximum Operating Frequency............. 400kHz Continuous Drain Current (TC=25°C) .......... 40A Continuous Drain Current (TC=100°C) ........ 15A (2) Maximum Power Dissipation ................. 2.7W Junction Temperature ...............................150°C Lead Temperature (Solder).......................260°C Storage Temperature .............. -55°C to +150°C Recommended Operation Conditions (3) VDD to VS .............................................8V to 24V Operating Junction Temp. (TJ). -40°C to +125°C MP6910 Rev. 1.04 1/3/2013 Thermal Resistance (4) θJA θJC TO220-3..................................45 ....... 3 .... °C/W Notes: 1) Exceeding these ratings may damage the device. 2) TA=+25℃. The maximum allowable power dissipation is a function of the maximum junction temperature TJ (MAX), the junction-to-ambient thermal resistance θJA, and the ambient temperature TA. The maximum allowable continuous power dissipation at any ambient temperature is calculated by PD (MAX) = (TJ (MAX)-TA)/θJA. Exceeding the maximum allowable power dissipation will cause excessive die temperature, and the regulator will go into thermal shutdown. Internal thermal shutdown circuitry protects the device from permanent damage. 3) The device is not guaranteed to function outside of its operating conditions. 4) Measured on JESD51-7, 4-layer PCB. www.MonolithicPower.com MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2013 MPS. All Rights Reserved. 2 MP6910- FAST TURN-OFF INTELLIGENT RECTIFIER ELECTRICAL CHARACTERISTICS VDD = 12V, TA= +25°C, unless otherwise noted. Parameter Drain-to-Source Breakdown Voltage VDD Voltage Range VDD UVLO Rising VDD UVLO Hysteresis Operating Current Light-Load Mode Current CONTROL CIRCUITRY SECTION VSS –VD Forward Voltage Turn-on Delay(5) Turn off Threshold (VSS-VD)(5) Turn-off Delay(5) Minimum On-time(5) Light-load-enter Delay Symbol Conditions V(BR)DSS ICC Typ 110 55 70 200 30 30 1.6 120 FSW=100kHz Vfwd TDon TDoff TMIN Min 100 8 5.0 0.8 VD =VSS TLL-Delay Light-load-enter Pulse Width TLL Light-load-enter Pulse Width TLL-H Hysteresis Light-load Mode Exit Pulse Width VLL-DS Threshold (VDS) POWER SWITCH SECTION Single Pulse Avalanche Current (6) IAS (6) Single Pulse Avalanche Energy EAS Drain-Source On-State Resistance RDS(ON) Input Capacitance Ciss Output Capacitance Coss Reverse Transfer Capacitance Crss DRAIN-SOURCE DIODE CHARACTERISTICS Reverse Recovery Time trr Diode Reverse Change Qrr -400 VGS=10V, ID=20A VDS=40V, f=1MHz 6.0 1.2 4.5 260 Max 24 7.0 1.5 8 360 85 45 Units V V V V mA μA mV ns mV ns μs μs 2.2 μs 0.2 μs -250 -150 mV 66 597 10.2 5110 334 150 A mJ mΩ pF pF pF 81 190 ns nC Notes: 5) Guaranteed by Design and Characterization. 6) Starting TJ=25°C, L=0.3mH PIN FUNCTIONS Pin # 1 2 3 MP6910 Rev. 1.04 1/3/2013 Name VDD VD VS Description Supply Voltage FET Drain FET Source, also used as reference for VDD www.MonolithicPower.com MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2013 MPS. All Rights Reserved. 3 MP6910- FAST TURN-OFF INTELLIGENT RECTIFIER BLOCK DIAGRAM VD VDD Logic Control Circuitry Driver VSS Figure 1—Function Block Diagram OPERATION The MP6910 supports operation in DCM and Quasi-Resonant Flyback converters. The control circuitry controls the gate in forward mode and will turn the gate off when the MOSFET current is fairly low. Blanking The control circuitry contains a blanking function. When it pulls the integrate Mosfet on/off, it makes sure that the on/off state at least lasts for some time. The turn on blanking time is ~1.6us, which determines the minimum on-time. During the turn on blanking period, the turn off threshold is not totally blanked, but changes the threshold voltage to ~+50mV (instead of -30mV). This assures that the part can always be turned off even during the turn on blanking period. (Albeit slower) Under-Voltage Lockout (UVLO) When the VDD is below UVLO threshold, the part is in sleep mode and the integrated Mosfet is never turned on. MP6910 Rev. 1.04 1/3/2013 Basic Operation The basic operations of flyback converter with MP6910 are: z Turn On Phase The switch current will first flow through the body diode of the integrate Mosfet, which generates a negative Vds across it (<500mV). The voltage is much smaller than the turn on threshold of the control circuitry (70mV), which turns on the integrate Mosfet after 200ns turn on delay (defined in Fig.2). z Conducting Phase When the integrated Mosfet is turned on, Vds becomes to rise according to its on resistance, as soon as Vds rises above the turn on threshold (-70mV), the control circuitry stops pulling up the gate driver, which leads the driver voltage of the integrate Mosfet dropped to larger the on resistance to ease the rise of Vds. By doing that, Vds is adjusted to be around -70mV even when the current through the switch is www.MonolithicPower.com MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2013 MPS. All Rights Reserved. 4 MP6910- FAST TURN-OFF INTELLIGENT RECTIFIER fairly small, this function can make the internal driver voltage fairly low when the mosfet is turned off to fast the turn off speed (this function is still active during turn on blanking period which means the integrate mosfet could still be turned off even with very small duty). Fig.3 shows synchronous rectification operation at heavy load condition. Due to the high current, the internal driver voltage will be saturated at first. After Vds goes to above -70mV, driver voltage decreases to adjust the Vds to typical -70mV. Fig.4 shows synchronous rectification operation at light load condition. Due to the low current, the driver voltage never saturates but begins to decrease as soon as the integrated mosfet is turned on and adjust the Vds. z Turn Off Phase When Vds rises to trigger the turn off threshold (-30mV), the driver voltage of the switch is pulled to low after about 20ns turn off delay (defined in Fig.2) by the control circuitry. Similar with turn-on phase, a 200ns blanking time is added after the switch is turned off to avoid error trigger. Light-load Latch-off Function The gate driver of integrate Mosfet in MP6910 is latched to save the driver loss at light-load condition to improve efficiency. The light-loadenter pulse width TLL is internal fixed (~2.2μs). When synchronous power switch conducting period keeps lower than TLL for longer than the light-load-enter delay (TLL-Delay), MP6910 enters light-load mode and latches off the integrate Mosfet (Fig.5 for detail). Mosfet of MP6910 is unlatched to restart the synchronous rectification (Fig.6 for detail). Typical System Implementations Fig.7 shows the typical system implementation for the IC supply derived from output voltage, which is available in low-side rectification and the output voltage is recommended to be in the VDD range of MP6910 (from 8V to 24V). If output voltage is out of the VDD range of MP6910 or high-side rectification is used, it is recommended to use an auxiliary winding from the power transformer for the IC supply, which is shown in Fig.8 and Fig.9. There is another non-auxiliary winding solution for the IC supply, which uses an external LDO circuit from the secondary transformer winding. See fig.10 and fig.11, compared with using auxiliary winding for IC supply, this solution has a bit higher power loss which is dissipate on the LDO circuit especially when the secondary winding voltage is high. VDS -30mV -70mV tDon tDoff Internal Driver Voltage 2V Figure 2—Turn on and Turn off delay During light-load mode, MP6910 monitors the integrate Mosfet body diode conducting period by sensing VDS (when VDS exceeds the light-load mode exit pulse width threshold VLL-DS, MP6910 considers the integrate Mosfet body diode conducting time finishes). If the Mosfet body diode conduction time is longer than TLL+TLL-H (TLL-H, light-load-enter pulse width hysteresis), the light-load mode is finished and the integrate MP6910 Rev. 1.04 1/3/2013 www.MonolithicPower.com MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2013 MPS. All Rights Reserved. 5 MP6910- FAST TURN-OFF INTELLIGENT RECTIFIER SR Gate Normal Mode V DS Light Load Mode -30mV 120 µs -70mV TLL T LL T LL ISD Internal Driver voltage Switching Current t0 t1 t2 Load become light Figure 3—Synchronous Rectification Operation at heavy load Figure 5—Enter Light Load Mode SR Gate VDS Light Load Mode -30mV Normal Mode -70mV TLL +T LL- H T LL+TLL-H TLL+TLL-H TLL+TLL-H ISD Internal Driver voltage Switching Current t0 t1 t2 Load become heavy Figure 6—Exit Light Load Mode Figure 4—Synchronous Rectification Operation at light load MP6910 Rev. 1.04 1/3/2013 www.MonolithicPower.com MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2013 MPS. All Rights Reserved. 6 MP6910- FAST TURN-OFF INTELLIGENT RECTIFIER C1 1 VDD MP6910 2 VD C2 VSS 3 Figure 7—IC supply derived directly from output voltage R1 C1 VDD D1 1 MP6910 2 VD C2 VSS 3 Figure 8—IC supply derived from auxiliary winding in low-side rectification 3 VSS VD 2 C1 MP6910 VDD 1 C2 D1 R1 Figure 9—IC supply derived from auxiliary winding in high-side rectification MP6910 Rev. 1.04 1/3/2013 www.MonolithicPower.com MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2013 MPS. All Rights Reserved. 7 MP6910- FAST TURN-OFF INTELLIGENT RECTIFIER R1 C1 D2 D1 R2 VDD 1 MP6910 2 C2 VSS VD 3 Figure 10—IC supply derived from secondary winding in low-side rectification 3 VSS VD 2 C1 MP6910 D1 R1 VDD R2 1 D2 C2 Figure 11—IC supply derived from secondary winding in high-side rectification MP6910 Rev. 1.04 1/3/2013 www.MonolithicPower.com MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2013 MPS. All Rights Reserved. 8 MP6910- FAST TURN-OFF INTELLIGENT RECTIFIER PACKAGE INFORMATION 0.390 (9.91) 0.415 (10.54) 0.175 (4.45) 0.185 (4.70) 0. 045 (1.14) 0. 055 (1.40) 0. 100 (2. 54) 0. 120 (3. 05) 0. 230 (5. 84) 0. 270 (6. 86) ? 0.147 (3.73) ? 0.155 (3.94) 0.560 (14. 22) 0.650 (16. 51) E-PIN ID 0. 330 (8. 38) 0. 355 (9. 02) 0. 130 (3. 30) 0. 160 (4. 06) 0.095 (2.41) 0.115 (2.92) 0.520 (13.21) 0.550 (13.97) 0. 50 (1.27) TYP 0.100 (2.54) BSC 0. 014 (0.36) 0. 022 (0.56) 0. 027 (0.69) 0. 037 (0.94) TOP VIEW SIDE VIEW NOTE: 1) CONTROL DIMENSION IS IN INCHES. DIMENSION IN BRACKET IS IN MILLIMETERS. 2) PACKAGE LENGTH DOES NOT INCLUDE MOLD FLASH , PROTRUSIONS OR GATE BURRS. 3) PACKAGE WIDTH DOES NOT INCLUDE INTERLEAD FLASH OR PROTRUSIONS . 4) DRAWING CONFORMS TO JEDEC TO-220 6) DRAWING IS NOT TO SCALE. MP6910 Rev. 1.04 1/3/2013 www.MonolithicPower.com MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2013 MPS. All Rights Reserved. 9 MP6910- FAST TURN-OFF INTELLIGENT RECTIFIER 0.392 (9.96) 0.408 (10.36) 0.175 (4.45) 0.185 (4.70) 0.045 (1.14) 0.055 (1.40) 0.100 (2. 54) 0.120 (3. 05) 0.230 (5. 84) 0.270 (6. 86) ? 0.142 (3.60) ? 0.150 (3.80) 0.560 (14.22) 0.650 (16.51) E-PIN ID 0.330 (8. 38) 0.355 (9. 02) 0.130 (3. 30) 0.160 (4. 06) 0.095 (2.41) 0.115 (2.92) 0.528 (13.40) 0.567 (14.40) 0.50 (1.27) TYP 0.100 (2.54) BSC 0. 015 (0. 39) 0. 024 (0. 61) 0.027 (0. 69) 0.037 (0. 94) TOP VIEW SIDE VIEW NOTE: 1) CONTROL DIMENSION IS IN INCHES. DIMENSION IN BRACKET IS IN MILLIMETERS. 2) PACKAGE LENGTH DOES NOT INCLUDE MOLD FLASH , PROTRUSIONS OR GATE BURRS. 3) PACKAGE WIDTH DOES NOT INCLUDE INTERLEAD FLASH OR PROTRUSIONS . 4) DRAWING CONFORMS TO JEDEC TO-220 6) DRAWING IS NOT TO SCALE. NOTICE: The information in this document is subject to change without notice. Users should warrant and guarantee that third party Intellectual Property rights are not infringed upon when integrating MPS products into any application. MPS will not assume any legal responsibility for any said applications. MP6910 Rev. 1.04 1/3/2013 www.MonolithicPower.com MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2013 MPS. All Rights Reserved. 10