MP6002DN-LF-Z

MP6002 Monolithic Flyback/Forward DC-DC Converter The Future of Analog IC Technology DESCRIPTION FEATURES The MP6002 is a monolithic Flyback/Forward DC-DC converter which includes a 150V power switch and is capable of delivering up to 30W output power. It can also be used for boost and SEPIC applications.              The MP6002 uses the fixed-frequency peak current mode primary controller architecture. It has an internal soft-start, auto-retry, and incorporates over current, short circuit, and over-voltage protection. The MP6002 can also skip cycles to maintain zero load regulation. It has a direct optocoupler interface which bypasses the internal error amplifier when an isolated output is desired. Integrated 0.45Ω 150V Power Switch Cycle-by-Cycle Current Limiting Programmable Switching Frequency Duty Cycle Limiting with Line Feed Forward Integrated 100V Startup Circuit Internal Slope Compensation Disable Function Built-in Soft-Start Line Under Voltage Lockout Line Over Voltage Protection Auto-Restart for Opened/Shorted Output Zero Load Regulation Thermal Shutdown APPLICATIONS The MP6002 is ideal for telecom applications, and is available in a compact, thermally enhanced SO8 package with an exposed pad.    Telecom Equipment VoIP Phones, Power over Ethernet (PoE) Distributed Power Conversion 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 Efficiency vs Load Current VOUT +VIN D2 B330A 36V~72V D1 1N4148 5V @ 3A R6 30.1kΩ R7 402Ω C2 470μ F EFFICIENCY R1 249kΩ PC357 2 C1 2.2μ F x 2 6 3 R2 9.76kΩ 4 C4 10μ F R8 1MΩ SW LINE VIN VCC MP6002 GND FB COMP R9 475kΩ RT R10 20.5kΩ 8 7 C3 1 R3 10nF 5.6kΩ 5 R4 1 kΩ TL431 R5 10kΩ -VIN 0 0.5 1 1.5 2 2.5 3 3.5 LOAD CURRENT (A) MP6002 Rev. 1.0 12/4/2013 www.MonolithicPower.com MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2013 MPS. All Rights Reserved. 1 MP6002 – MONOLITHIC FLYBACK/FORWARD DC-DC CONVERTER ORDERING INFORMATION Part Number* Package Top Marking Temperature MP6002DN SOIC8E MP6002DN –40C to +85C * For Tape & Reel, add suffix –Z (eg. MP6002DN–Z). For RoHS compliant packaging, add suffix –LF (eg. MP6002DN–LF–Z) PACKAGE REFERENCE TOP VIEW GND 1 8 SW LINE 2 7 VIN FB 3 6 VCC COMP 4 5 RT ABSOLUTE MAXIMUM RATINGS (1) VSW .............................................–0.5V to +180V VIN .............................................–0.3V to +120V All Other Pins ..............................–0.3V to +6.5V (2) Continuous Power Dissipation (TA = +25°C) ............................................................. 2.5W Junction Temperature ...............................150°C Lead Temperature ....................................260°C Storage Temperature.............. –65°C to +150°C Recommended Operating Conditions (3) Supply Voltage VCC ...........................4.5 V to 6V Output Voltage VSW ....................–0.5V to +150V Input Voltage VIN .........................+10V to +100V Operating Temperature............. –40C to +85C MP6002 Rev. 1.0 12/4/2013 Thermal Resistance (4) θJA θJC SOIC8E (Exposed Pad) ..........50 ...... 10 ... 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 board. www.MonolithicPower.com MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2013 MPS. All Rights Reserved. 2 MP6002 – MONOLITHIC FLYBACK/FORWARD DC-DC CONVERTER ELECTRICAL CHARACTERISTICS VCC = 5.0V, VLINE = 1.8V, RT = 20k, TA = +25C, unless otherwise noted. Parameter Quiescent Supply Current Line OV Threshold Voltage Line OV Hysteresis Line UV Threshold Voltage Line UV Hysteresis VCC Upper Threshold Voltage VCC Lower Threshold Voltage VCC Over Voltage Threshold Voltage Feedback Voltage Feedback Input Current Error Amplifier Gain Bandwidth (5) Error Amplifier DC Gain (5) Comp Output Source Current Comp Output Sink Current Switch-On Resistance Switch Leakage Current Minimum Oscillating Frequency Maximum Oscillating Frequency Thermal Shutdown (5) Thermal Shutdown Hysteresis (5) Current Limit (5) Startup Current Symbol Condition ICC 1.2V < VLINE < 3.2V, VFB = 1.3V VCC = 5.0V VCC = 5.0V VCC = 5.0V VCC = 5.0V VFB IFB GBW AV IOH IOL RON ILK FMIN FMAX ILIM Ist Min 5.75 4.30 Typ 1.0 3 300 1.21 100 6.0 4.50 6.25 4.70 Units mA V mV V mV V V 6.3 6.6 6.9 V 1.16 1.21 50 1.26 V nA MHz dB mA mA Ω µA kHz kHz C C A mA 2.85 1.16 VFB = 1.2V 1 60 VFB = 1.0V, VCOMP = 0.5V VFB = 1.4V, VCOMP = 2.5V VSW = 0.1V VSW = 150V RT = 100k RT = 10k VIN = 20V, VCC = 4.0V 2 2 0.45 1 55 550 150 30 4 3 Max 1.5 3.15 1.26 Note: 5) Guaranteed by design, not production tested. MP6002 Rev. 1.0 12/4/2013 www.MonolithicPower.com MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2013 MPS. All Rights Reserved. 3 MP6002 – MONOLITHIC FLYBACK/FORWARD DC-DC CONVERTER PIN FUNCTIONS Pin # 1 2 3 4 5 6 7 8 Name Description GND LINE Ground. Power return and reference node. UV/OV Set Point. Short to ground to turn the controller off. Regulation Feedback Input. Inverting input of the error amplifier. The non-inverting is internally FB connected to 1.2V COMP Error Amplifier Output. Oscillator Resistor and Synchronous Clock Pin. Connect an external resistor to GND for RT oscillator frequency setting. It can be used as a synchronous input from external oscillator clock. VCC Supply Bias Voltage. A capacitor no less than 1uF is recommended to connect between GND. VIN High Voltage Startup Circuit Supply. Output Switching Node. High voltage power N-Channel MOSFET drain output. The internal SW start bias current is supplied from this pin. MP6002 Rev. 1.0 12/4/2013 www.MonolithicPower.com MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2013 MPS. All Rights Reserved. 4 MP6002 – MONOLITHIC FLYBACK/FORWARD DC-DC CONVERTER TYPICAL PERFORMANCE CHARACTERISTICS VIN = 48V, VOUT = 5V, TA = +25ºC, unless otherwise noted. Steady State Test Synchronize Programmable Synchronize Programmable VIN = 48V, VOUT = 5V, IOUT = 3A FSW = 55KHz, FSYNC=60KHz. FSW = 55KHz, FSYNC=550KHz VOUT AC Coupled 50mV/div. VOUT 5V/div. VOUT 5V/div. VSYNC 5V/div. VSYNC 5V/div. VSW 50V/div. VSW 50V/div. IPRI 1A/div. VSW 50V/div. IPRI 500mA/div. IPRI 1A/div. 1us/div. 10us/div. Short Circuit State VIN = 48V, IOUT = 3A 2us/div. Short Circuit Entry Short Circuit Recovery VIN = 48V, IOUT = 3A VIN = 48V, IOUT = 3A VOUT 5V/div. VOUT 2V/div. VCC 2V/div. VSW 100V/div. VCC 2V/div. VOUT 5V/div. VCC 2V/div. VSW 100V/div. VSW 100V/div. IPRI 2A/div. IPRI 2A/div. 40ms/div. IPRI 2A/div. 20ms/div. Load Transient Response 40ms/div. Current Limit vs Duty Cycle VIN = 48V, VOUT = 5V, IOUT = 1.5A~3A @ 2.5A/us 5.00 Current Limit (A) 4.75 VOUT 50mV/div. IPRI 1A/div. 400υs/div. 4.50 4.25 4.00 3.75 3.50 3.25 3.00 10 20 30 40 50 60 70 Duty Cycle(%) MP6002 Rev. 1.0 12/4/2013 www.MonolithicPower.com MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2013 MPS. All Rights Reserved. 5 MP6002 – MONOLITHIC FLYBACK/FORWARD DC-DC CONVERTER TYPICAL PERFORMANCE CHARACTERISTICS VIN = 48V, VOUT = 5V, TA = +25ºC, unless otherwise noted. MP6002 Rev. 1.0 12/4/2013 www.MonolithicPower.com MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2013 MPS. All Rights Reserved. 6 MP6002 – MONOLITHIC FLYBACK/FORWARD DC-DC CONVERTER OPERATION The MP6002 uses programmable fixedfrequency, peak current-mode PWM with a single-ended primary architecture to regulate the output voltage. The MP6002 incorporates features such as protection circuitry and an integrated high voltage power switch into a small 8-pin SOIC. This product targets high performance, cost effective DC-DC converter applications. 6 VCC + 6.5V 4.5V -LINE 2 + 3.0V 1.2V OVLO -- REGULATOR IBIAS REF + STARTUP UVLO -- 7 VIN 8 SW THERMAL MONITOR COMP 4 ERROR AMPLIFIER 1.2V FB 3 + CONTROL LOGIC -- EA -- + 1 GND PWM COMPARATOR SOFT-START CURRENT LIMIT CLOCK RT 5 -+ CURRENT LIMIT COMPARATOR + 1.0V -- OSC SLOPE COMP Σ LEB CURRENT SENSE Figure 1—Functional Block Diagram MP6002 Rev. 1.0 12/4/2013 www.MonolithicPower.com MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2013 MPS. All Rights Reserved. 7 MP6002 – MONOLITHIC FLYBACK/FORWARD DC-DC CONVERTER High Voltage Startup The MP6002 features a 100V startup circuit, see Figure 1. When power is applied, the capacitor at the VCC pin is charged through the VIN pin. When the voltage at the VCC pin crosses 6.0V without fault, the controller is enabled. The VCC pin is then disconnected from the VIN pin and VCC voltage is discharged via the operating current. When VCC drops to 4.5V, the VCC pin is reconnected to the VIN pin and VCC will be recharged. The voltage at the VCC pin repeats this ramp cycle between 4.5V and 6.0V. VIN needs to be higher than 10V in order to keep high voltage startup circuit working properly. This can be guaranteed by setting input UVLO≥10V. It is also recommended that the capacitor at VCC pin be no less than 1uF to achieve stable operation. The VCC pin can be powered with a voltage higher than 4.5V from an auxiliary winding to reduce the power dissipated in the internal start-up circuit. The VCC pin is internally clamped at 8V. Under-Voltage and Over-Voltage Detection The MP6002 includes a line monitor circuit. Two external resistors form a voltage divider from the input voltage to GND; its tap connects to the LINE pin. The controller is operational when the voltage at the UV/OV pin is between 1.2V and 3V. When the voltage at the UV/OV pin goes out of this operating range, the controller is disabled and goes into standby mode. The LINE pin can also be used as a remote enable. Grounding the UV/OV pin will disable the controller. Error Amplifier The MP6002 includes an error amplifier with its non-inverting input connected to internal 1.2V reference voltage. The regulated voltage is fed back through a resistor network or an optocoupler to the FB pin. Figure 2 shows some common error amplifier configurations. 6 VCC D1 1.2V C1 + EA -- R1 FB COMP 3 4 C2 PRIMARY WINDING R3 C3 R2 (a) Using Primary winding to provide feedback 6 VCC 1.2V + EA -- C2 COMP FB 3 4 R3 R2 (b) Feedback is from Secondary (Common Collector) Figure 2—Error Amplifier Configurations Synchronize Programmable Oscillator The MP6002 oscillating frequency is set by an external resistor from the RT pin to ground. The value of RT can be calculated from: RT  10k  550KHz fS The MP6002 can be synchronized to an external clock pulse. The frequency of the clock pulse must be higher than the internal oscillator frequency. The clock pulse width should be within 50ns to 150ns. The external clock can be coupled to the RT pin with a 100pF capacitor and a peak level greater than 3.5V. Duty Cycle Limiting with Line Feed Forward The MP6002 has a DMAX (maximum duty cycle) limit at 67.5% when the LINE pin voltage is equal to 1.3V. As VLINE increases, DMAX reduces. Maximum duty cycle can be calculated by:   2 .7 V D MAX     100%  2.7 V  VLINE  MP6002 Rev. 1.0 12/4/2013 www.MonolithicPower.com MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2013 MPS. All Rights Reserved. 8 MP6002 – MONOLITHIC FLYBACK/FORWARD DC-DC CONVERTER Limiting the duty cycle at high line voltage protects against magnetic saturation and minimizes the output sensitivity to line transients. Auto-Restart When VCC is biased from an auxiliary winding and an open loop condition occurs, the voltage at the VCC pin increases to 6.5V. When VCC crosses the threshold voltage, the auto-restart circuit turns off the power switch and puts the controller in standby mode. When VCC drops to 4.5V, the startup switch turns on to charge VCC up again. When VCC crosses 6.0V, the switch turns off and the standby current discharges VCC back to 4.5V. After repeating the ramp cycles between the two threshold voltages 15 times, the auto-restart circuit is disabled and the controller begins soft-start. Over Current Protection The MP6002 has cycle-by-cycle over current limit when the internal switch current peak value exceeds the set current limit threshold. Meanwhile, the output voltage starts to drop until FB is below the Under-Voltage (UV) threshold, typically 33% below the FB reference. Once a UV is triggered, the MP6002 enters hiccup mode to periodically restart the part (the MP6002 turns off the switch until Vcc repeats the ramp cycles between 4.5V to 6V for 15 times). This protection mode is especially useful when the output is dead-short to ground. The average short circuit input current is greatly reduced to alleviate the thermal issue and protect the regulator. The MP6002 exits the hiccup mode once the over current condition is removed. MP6002 Rev. 1.0 12/4/2013 www.MonolithicPower.com MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2013 MPS. All Rights Reserved. 9 MP6002 – MONOLITHIC FLYBACK/FORWARD DC-DC CONVERTER APPLICATION INFORMATION Switching Frequency The frequency (fS), has big effects on the selection of the transformer (Tr), the output cap, (C2), and the input cap, (C1). The higher the frequency, the smaller the sizes for Tr, C2, and C1. However, a higher frequency also leads to higher AC power losses in the power switch, control circuitry, transformer, and in the external interconnection. The general rule states that lower the output power, higher the optimum switching frequency. For low current (