MP6903 Fast Turn-off Intelligent Controller The Future of Analog IC Technology DESCRIPTION FEATURES The MP6903 is a low-drop diode emulator that, combined with an external switch, replaces Schottky diodes in high-efficiency LLC converters. The chip regulates the forward drop of an external switch to about 70mV and switches it off as soon as the voltage goes negative. MP6903 has a light-load sleep mode that reduces the quiescent current to < 300µA. Works with Standard and Logic-Level FETS Compatible with Energy Star, 1W Standby Requirements VDD Range from 8V to 24V Fast Turn-Off: Total Delay of 20ns Max 400kHz Switching Frequency <300µA Quiescent Current in Light Load Mode Supports DCM, CCM and CrCM Operation Supports High-Side and Low-Side Rectification Power Savings of Up to 1.5W for a Typical Notebook Adapter APPLICATIONS Industrial Power Systems Distributed Power Systems Battery Powered Systems LLC 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 U1 MP6903 Output R2 120k EN Or Left Open Qa Cs R3 10k C2 1nF R1 100k R5 1k Ls 8 1 PGND VG 2 EN NC 7 6 3 LL VDD 4 VD VSS 5 VG1 C1 2.2uF VG1 Cin Q1 Qb Lm Output C4 VG2 GND R6 1k Q2 MP6903 EN 1 2 C3 VG EN NC 3 LL VDD 4 VD VSS 1nF R4 100k PGND 8 VG2 7 6 5 U2 MP6903 Rev. 1.04 1/31/2013 www.MonolithicPower.com MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2013 MPS. All Rights Reserved. 1 MP6903- FAST TURN-OFF INTELLIGENT CONTROLLER ORDERING INFORMATION Part Number* Package SOIC8 MP6903DS Top Marking MP6903 * For Tape & Reel, add suffix –Z (e.g. MP6903DS–Z); For RoHS Compliant Packaging, add suffix –LF (e.g. MP6903DS–LF–Z) PACKAGE REFERENCE TOP VIEW PGND 1 8 VG EN 2 7 NC LL 3 6 VDD VD 4 5 VSS ABSOLUTE MAXIMUM RATINGS (1) VDD to VSS ......................................-0.3V to +27V PGND to VSS ................................-0.3V to +0.3V VG to VSS ......................................... -0.3V to VDD VD to VSS .....................................-0.7V to +180V LL, EN to VSS ...............................-0.3V to +6.5V Maximum Operating Frequency............. 400kHz Continuous Power Dissipation (TA=25°C) (2) ............................................................. 1.4W Junction Temperature ...............................150°C Lead Temperature (Solder).......................260°C Storage Temperature .............. -55°C to +150°C Recommended Operation Conditions (3) Thermal Resistance (4) θJA θJC SOIC8 .....................................90 ...... 45 ... °C/W Notes: 1) Exceeding these ratings may damage the device. 2) The maximum allowable power dissipation is a function of the maximum junction temperature TJ(MAX), the junction-toambient 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. VDD to VSS ............................................8V to 24V Operating Junction Temp. (TJ).... -40°C to +125°C MP6903 Rev. 1.04 1/31/2013 www.MonolithicPower.com MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2013 MPS. All Rights Reserved. 2 MP6903- FAST TURN-OFF INTELLIGENT CONTROLLER ELECTRICAL CHARACTERISTICS VDD = 12V, -40°C ≤TJ≤ 125°C, unless otherwise noted. Parameter VDD Voltage Range VDD UVLO Rising VDD UVLO hysteresis Operating Current Quiescent Current Symbol Conditions ICC Iq Shutdown Current Light-Load Mode Current Thermal Shutdown (5) Thermal Shutdown Hysteresis (5) Enable UVLO Rising Enable UVLO Hysteresis Internal Pull-up Current on EN Pin CONTROL CIRCUITRY SECTION VSS –VD Forward Voltage CLOAD=5nF, fSW=100kHz VSS-VD=0.5V VDD =4V VDD=20V, EN=0V 170 30 1.1 Vfwd 55 tDon CLOAD = 5nF tDon CLOAD = 10nF Turn-on delay Input Bias Current on VD Pin Minimum On-Time Light-Load-Enter Delay Light-Load-Enter Pulse Width Light-Load-Enter Pulse Width Hysteresis Light-Load Resistor Value Light-Load Mode Exit Pulse Width Threshold (VDS) Light-Load Mode Enter Pulse Width Threshold (VGS) (5) GATE DRIVER SECTION VG (Low) tLL-Delay tLL VD = 180V CLOAD = 5nF RLL=100kΩ RLL=100kΩ tLL-H RLL=100kΩ tMIN 0.4 80 1.3 Typ 6.0 1 8 2 190 350 290 180 40 1.5 0.2 Max 24 7.0 1.2 10 3 260 420 400 190 50 1.9 0.4 Units V V V mA mA 10 15 µA 70 250 650 400 1200 0.5 0.8 120 1.75 85 380 mV 680 3 1.2 150 2.2 0.2 30 VLL-DS -400 VLL-GS -250 13 VDD-2.2 0 VD=VSS VD =VSS, CLOAD=5nF, RGATE=0Ω VD =VSS, CLOAD=10nF, RGATE=0Ω 3V <VG<10V µA °C °C V V ns ns µA µs µs µs 300 kΩ -150 mV V 0.05 14.5 0.1 16 V V 30 60 mV 100 tDoff tDoff µA µs 1.0 ILOAD=1mA VDD >17V VDD <17V Turn Off Threshold (VSS-VD) (5) Turn Off Threshold During Blanking Time (VSS-VD) (5) Turn-Off Propagation Delay Pull Down Impedance Pull Down Current (5) -20°C≤TJ≤125°C -40°C≤TJ<-20°C -20°C≤TJ≤125°C -40°C≤TJ<-20°C RLL VG (High) Turn-Off, Total Delay Min 8 4.8 0.8 15 60 60 1 2 mV 120 120 2 ns ns ns Ω A Notes: 5) Guaranteed by Design and Characterization. Not tested in Production. MP6903 Rev. 1.04 1/31/2013 www.MonolithicPower.com MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2013 MPS. All Rights Reserved. 3 MP6903- FAST TURN-OFF INTELLIGENT CONTROLLER PIN FUNCTIONS Pin # 1 2 3 4 5 6 7 8 MP6903 Rev. 1.04 1/31/2013 Name PGND EN LL VD VSS VDD NC VG Description Power Ground. Return for driver switch. Enable. Active high. Light Load Time Set. Connect a resistor to set the light load timing. MOSFET Drain Voltage Sense. Ground. Also used as reference for VD. Supply Voltage. No Connection. Gate Drive Output. www.MonolithicPower.com MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2013 MPS. All Rights Reserved. 4 MP6903- FAST TURN-OFF INTELLIGENT CONTROLLER TYPICAL PERFORMANCE CHARACTERISTICS VDD = 12V, unless otherwise noted. VFWD vs. Temperature 80 70 65 -50 0 50 100 150 2.4 QUIESCENT CURRENT (mA) TURN OFF THRESHOLD (V) -25 -30 -35 -40 -50 Shutdown Current vs. Temperature 0 50 100 150 100 50 100 6.5 6 5.5 5 150 -50 330 1.6 EN UVLO RISING (V) 1.7 310 290 270 MP6903 Rev. 1.04 1/31/2013 50 100 1.4 1.2 150 0 50 100 150 0 50 100 7.6 7.4 7.2 7 6.8 6.6 -50 150 EN UVLO Rising vs. Temperature 350 0 1.6 CLOAD=5nF, fSW=100kHz 7.8 Light Load Mode Current vs. Temperature 250 -50 1.8 Operation Current vs. Temperature OPERATION CURRENT (mA) VDD UVLO RISING (V) 200 0 2 VDD UVLO Rising vs. Temperature 7 50 -50 2.2 1 -50 150 50 100 150 CLOAD=5nF 700 600 1.5 1.4 1.3 1.2 -50 0 Turn On Delay vs. Temperature TURN ON DELAY (ns) VFWD (mV) Quiescent Current vs. Temperature -20 75 60 Turn off threshold vs. Temperature 0 50 100 150 500 400 300 200 100 0 -50 0 50 www.MonolithicPower.com MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2013 MPS. All Rights Reserved. 100 150 5 MP6903- FAST TURN-OFF INTELLIGENT CONTROLLER TYPICAL PERFORMANCE CHARACTERISTICS (continued) VDD = 12V, unless otherwise noted. Turn On Delay vs. Temperature CLOAD=10nF 90 TURN OFF DELAY (ns) TURN ON DELAY (ns) CLOAD=5nF CLOAD=10nF 90 80 80 1,200 1,000 800 600 400 200 0 -50 Turn Off Delay vs. Temperature TURN OFF DELAY (ns) 1,400 Turn Off Delay vs. Temperature 70 60 50 40 30 20 0 50 100 150 60 50 40 30 20 10 10 0 -50 70 0 50 100 0 -50 150 Minimum On Time vs. Temperature 1.8 0.7 1.7 0.6 1.6 100 1.5 -50 150 (ns) 0.8 (5) 1.9 TURN-OFF THRESHOLD 0.9 50 100 150 60 2 0 50 Turn-off Threshold(5) vs. Temperature 1.0 0.5 -50 0 0 50 100 150 50 40 30 20 10 0 -50 0 50 100 150 Operation in LLC Resonant Converter Operation in LLC Resonant Converter Operation in LLC Resonant Converter VIN=250V, VOUT=12V, IOUT=15A DCM VIN=263V, VOUT=12V, IOUT=15A CRCM VIN=280V, VOUT=12V, IOUT=15A CCM VDS 20V/div VDS 20V/div VG 5V/div VG 5V/div ISR 10A/div ISR 10A/div MP6903 Rev. 1.04 1/31/2013 VDS 20V/div VG 5V/div ISR 10A/div www.MonolithicPower.com MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2013 MPS. All Rights Reserved. 6 MP6903- FAST TURN-OFF INTELLIGENT CONTROLLER FUNCTIONAL BLOCK DIAGRAM Figure 1: Functional Block Diagram OPERATION The MP6903 supports operation in discontinuous current mode (DCM), continuous current mode (CCM), and critical conduction mode (CrCM) condition. Operating in either a DCM or CrCM condition, the control circuitry controls the gate in forward mode and will turn the gate off when the MOSFET current goes low. In CCM operation, the control circuitry turns off the gate when very fast transients occur. Blanking The control circuitry contains a blanking function. When the MOSFET turns on or off, the blanking function ensures that the previous state extends for some minimum time period. The turn-on blanking time is ~0.8µs. During the turn-on blanking period, the turn-off threshold is not totally blanked, but changes the threshold voltage to approximately 100mV (instead of 0mV). This assures that the part can always turn off even during the turn-on blanking period. (The synchronous period is recommended to be greater than 0.8μs in CCM in the LLC Converter to avoid shoot-through.) MP6903 Rev. 1.04 1/31/2013 VD Clamp A high-voltage JFET is used at the input because VD can go as high as 180V. To avoid excessive currents when VG goes below -0.7V, add a small resistor between VD and the drain of the external MOSFET. Under-Voltage Lockout (UVLO) When VDD drops below the UVLO threshold, the part goes into sleep mode and a 10kΩ resistor pulls the VG pin low. Enable pin EN is internal pulled up by the regulator from VDD with a ~15uA current source. Leave this pin open if unused. When use external signal to control EN, it is highly recommended the pull down current be larger than 15uA to make sure the EN pin can be pulled to low. www.MonolithicPower.com MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2013 MPS. All Rights Reserved. 7 MP6903- FAST TURN-OFF INTELLIGENT CONTROLLER Thermal shutdown If the junction temperature of the chip exceeds 180°C, the VG will be pulled low and the part stops switching. The part will resume normal function after the junction temperature has dropped to 150°C. Turn-On Phase When the synchronous MOSFET is on, current flows through its body diode and generates a negative VDS. This body diode voltage drop (< 500mV) is much smaller than the turn-on threshold of the control circuitry (-70mV), which then pulls the gate driver voltage high to turn on the synchronous MOSFET after about 250ns turn-on delay (shown in Figure 2). When the turn-on delay ends, turn-on starts with a blanking time (minimum on-time: ~0.8µs), and the turn-off threshold changes from +30mV to +100mV. This blanking time helps to avoid errors around the turn-off threshold caused by turn-on ringing of the synchronous MOSFET. Figure 2: Turn On/Off Timing Diagram Conducting Phase When the synchronous MOSFET turns on, VDS rises according to the MOSFET’s ON resistance. When VDS rises above the turn-on threshold (70mV), the control circuitry stops pulling up the gate driver, so the gate voltage is pulled down by the internal pull-down resistance (10kΩ) and leakage to increase the ON resistance of the synchronous MOSFET, which to limit the VDS slew rate, stabilizes VDS to around -70mV even when the current through the MOSFET is fairly small. This function limits the driver voltage when the synchronous MOSFET is turned off (this function is still active during turn-on blanking, MP6903 Rev. 1.04 1/31/2013 which means the gate driver could still be turnedoff even with very small duty cycles of the synchronous MOSFET). Turn-Off Phase When VDS triggers the turn-off threshold (30mV), the gate voltage is pulled to low after a 20ns turnoff delay (shown in Figure 2) by the control circuitry. Figure 3 shows synchronous rectification operation at heavy load. The gate driver initially saturates due to the high current. After VDS rises above -70mV, the gate driver voltage decreases to adjust the VDS to around -70mV. Figure 4 shows synchronous rectification operation at light load. The gate driver voltage never saturates due to the low current, but decreases as soon as the synchronous MOSFET turns on and adjusts the VDS. Figure 3: Synchronous Rectification Operation at Heavy Load Figure 4: Synchronous Rectification Operation at Light Load www.MonolithicPower.com MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2013 MPS. All Rights Reserved. 8 MP6903- FAST TURN-OFF INTELLIGENT CONTROLLER Light-Load Latch-Off Function The gate driver of MP6903 is latched to save the driver loss at light-load condition to improve efficiency. See Figure5, when the synchronous MOSFET’s conducting period keeps lower than light load timing (TLL) for longer than the lightload-enter delay (TLL-Delay), MP6903 enters lightload mode and latches off the gate driver. Here the synchronous MOSFET’s conducting period is from turn on of the gate driver to the moment when VGS drops to below 1V (VLL_GS). Normal Mode MP6903 is unlatched to restart the synchronous rectification, see Figure6. For MP6903, the light load enter timing (TLL) is programmable by connecting a resistor (RLL) on LL pin, by monitoring the LL pin current (the LL pin voltage keeps at ~2V internally), TLL is set as following (a 1nF capacitor is recommended to decouple the noise on this pin): TLL RLL (k ) 2.2us 100k Light Load Mode TLL-dELAY tLL tLL tLL Secondary Side Current Figure 5: MP6903 Enters Light Load Mode Figure 6: MP6903 Exits Light Load Mode During light-load mode, MP6903 monitors the synchronous MOSFET’s body diode conducting period by sensing the time duration of the VDS below -250mV(VLL_DS). If it is longer than TLL+TLLH (TLL-H, light-load-enter pulse width hysteresis), the light-load mode is finished and gate driver of MP6903 Rev. 1.04 1/31/2013 www.MonolithicPower.com MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2013 MPS. All Rights Reserved. 9 MP6903- FAST TURN-OFF INTELLIGENT CONTROLLER PACKAGE INFORMATION SOIC8 0.189(4.80) 0.197(5.00) 0.050(1.27) 0.024(0.61) 8 5 0.063(1.60) 0.150(3.80) 0.157(4.00) PIN 1 ID 1 0.228(5.80) 0.244(6.20) 0.213(5.40) 4 TOP VIEW RECOMMENDED LAND PATTERN 0.053(1.35) 0.069(1.75) SEATING PLANE 0.004(0.10) 0.010(0.25) 0.013(0.33) 0.020(0.51) 0.0075(0.19) 0.0098(0.25) SEE DETAIL "A" 0.050(1.27) BSC SIDE VIEW FRONT VIEW 0.010(0.25) x 45o 0.020(0.50) GAUGE PLANE 0.010(0.25) BSC 0o-8o 0.016(0.41) 0.050(1.27) DETAIL "A" 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) LEAD COPLANARITY (BOTTOM OF LEADS AFTER FORMING) SHALL BE 0.004" INCHES MAX. 5) DRAWING CONFORMS TO JEDEC MS-012, VARIATION AA. 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. MP6903 Rev. 1.04 1/31/2013 www.MonolithicPower.com MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2013 MPS. All Rights Reserved. 10