STR-X6729 Off-Line Quasi-Resonant Switching Regulators Features and Benefits ▪ Quasi-resonant topology IC Low EMI noise and soft switching ▪ Bottom-skip mode Improved system efficiency over the entire output load by avoiding increase of switching frequency ▪ Standby mode Lowers input power at very light output load condition ▪ Avalanche-guaranteed MOSFET Improves system-level reliability and does not require VDSS derating ▪ 450 VDSS / 0.189 Ω RDS(on) ▪ Various protections Improved system-level reliability ▫ Pulse-by-pulse drain overcurrent limiting ▫ Overvoltage Protection (bias winding voltage sensing), with latch ▫ Overload Protection with latch ▫ Maximum on-time limit Package: 7-Pin TO-3P Description The STR-X6729 is a quasi-resonant topology IC designed for SMPS applications. It shows lower EMI noise characteristics than conventional PWM solutions, especially at greater than 2 MHz. It also provides a soft-switching mode to turn on the internal MOSFET at close to zero voltage (VDS bottom point) by use of the resonant characteristic of primary inductance and a resonant capacitor. The package is a fully molded TO-3P, which contains the controller chip (MIC) and MOSFET, enabling output power up to 460 W at 120 VAC input. The bottom-skip mode skips the first bottom of VDS and turns on the MOSFET at the second bottom point, to minimize an increase of operating frequency at light output load, improving system-level efficiency over the entire load range. A standby mode is executed by clamping the secondary output. In general applications, standby mode reduces input power. The soft-start mode minimizes surge voltage and reduces power stress to the MOSFET and to the secondary rectifying diodes during the start-up sequence. Various protections such as overvoltage, overload, overcurrent, maximum on-time protections and avalanche-energy guaranteed MOSFET secure good system-level reliability. Continued on the next page… Not to scale Typical Application 28103.30-8 STR-X6729 Off-Line Quasi-Resonant Switching Regulators Description (continued) Applications include the following: ▪ Set Top Box ▪ LCD PC monitor, LCD TV ▪ Printer, Scanner ▪ SMPS power supplies Selection Guide Part Number Package STR-X6729 TO-3P Absolute Maximum Ratings at TA = 25°C Parameter Drain Current1 Maximum Switching Current2 Single Pulse Avalanche Energy3 Input Voltage for Controller (MIC) SS/OLP Terminal Voltage FB Terminal Inflow Current FB Terminal Voltage OCP/BD Terminal Voltage MOSFET Power Dissipation4 Symbol IDpeak IDmax EAS VCC VSSOLP IFB VFB VOCPBD PD1 Conditions Single pulse TA = –20°C to 125°C Single pulse, VDD = 30 V, L = 50 mH, ILpeak = 4.2 A IFB within the limits of IFB With infinite heatsink Without heatsink VCC × ICC Recommended operation temperature, see cautions Controller (MIC) Power Dissipation PD2 Operating Internal Leadframe Temperature TF Operating Ambient Temperature TOP Storage Temperature Tstg Channel Temperature Tch 1Refer to MOSFET ASO curve 2I DMAX is the drain current determined by the drive voltage of the IC and the threshold voltage, Vth, of the MOSFET 3Refer to Avalanche Energy Derating curve 4Refer to MOSFET Ta-PD1 curve Rating 22 22 472 35 –0.5 to 6.0 10 –0.5 to 9.0 –1.5 to 5.0 46 2.8 0.8 –20 to 125 –20 to 125 –40 to 125 150 Unit A A mJ V V mA V V W W W °C °C °C °C All performance characteristics given are typical values for circuit or system baseline design only and are at the nominal operating voltage and an ambient temperature, TA, of 25°C, unless otherwise stated. Allegro MicroSystems, Inc. 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 2 STR-X6729 Off-Line Quasi-Resonant Switching Regulators Functional Block Diagram Terminal List Table Number Name Description Functions 1 D Drain MOSFET drain 2 S Source MOSFET source 3 GND Ground terminal Ground 4 VCC Power supply terminal Input of power supply for control circuit 5 SS/OLP Soft Start/Overload Protection terminal Input to set delay for Overload Protection and Soft Start operation 6 FB Feedback terminal Input for Constant Voltage Control and Burst (intermittent) Mode oscillation control signals 7 OCP/BD Overcurrent Protection/Bottom Detection Input for Overcurrent Detection and Bottom Detection signals Allegro MicroSystems, Inc. 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 3 STR-X6729 Off-Line Quasi-Resonant Switching Regulators STR-X6729 MOS FET A.S.O. Curve STR-X6729 A.S.O. temperature derating coefficient curve Ta=25℃ Single Pulse 100 Determined by OnResistance 80 100μs ID[A] Drain Current 10 60 1ms 40 Apply ASO temperature derating coefficient from the left graph to this curve for evaluating actual operation’s safety 1 20 0 0 20 40 60 80 100 120 Internal frame temperature T F [℃] 0.1 1 10 100 V DS[V] Drain-to-Source Voltage 1000 STR-X6729 Avalanche energy derating curve 100 [EAS temperature derating coefficient (%) A.S.O. temperature derating coefficient (%) 100 80 60 40 20 0 25 50 75 100 Tch[℃] Channel temperature Allegro MicroSystems, Inc. 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 125 150 4 STR-X6729 Off-Line Quasi-Resonant Switching Regulators STR-X6729 MOSFET Ta-PD1 Curve STR-X6729 MIC TF-PD2 Curve 60 1 50 PD1=46[W] 0.8 P D2 [Ｗ] Power dissipation 0.6 30 0.4 20 0.2 Without heatsink 10 0 PD1=2.8[W] 0 20 40 60 80 100 120 140 160 40 60 80 100 120 140 Ta [℃] Ambient temperature STR-X6729 Transient thermal resistance curve 1 θch-c[℃/W] 0 20 TF[℃] Internal frame temperature 0 Transient thermal resistance PD1[Ｗ] Power dissipation With infinite heatsink 40 0.1 0.01 0.001 ｔ [sec] T im e Allegro MicroSystems, Inc. 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 5 STR-X6729 Off-Line Quasi-Resonant Switching Regulators ELECTRICAL CHARACTERISTICS Characteristic Symbol Test Conditions Min. Typ. Max. Units ELECTRICAL CHARACTERISTICS for Controller (MIC)1, valid at TA = 25°C, VCC = 20 V, unless otherwise specified Power Supply Start-up Operation Operation Start Voltage VCC(ON) VCC = 0→20 V 16.3 18.2 19.9 V Operation Stop Voltage VCC(OFF) VCC = 20→8.8 V 8.8 9.7 10.6 V Circuit Current In Operation ICC(ON) Circuit Current In Non-Operation ICC(OFF) Oscillation Frequency VCC = 15 V fosc Soft Start Operation Stop Voltage VSSOLP(SS) VSS/OLP increasing Soft Start Operation Charging Current ISSOLP(SS) VSS/OLP = 0 V – – 6 mA – – 100 μA 19 22 25 kHz 1.1 1.2 1.4 V –710 –550 –390 μA Normal Operation Bottom-Skip Operation Threshold Voltage 1 VOCPBD(BS1) –0.720 –0.665 –0.605 V Bottom-Skip Operation Threshold Voltage 2 VOCPBD(BS2) –0.485 –0.435 –0.385 V Overcurrent Detection Threshold Voltage VOCPBD(LIM) VOCP/BD falling –0.995 –0.940 –0.895 V VOCP/BD = –0.95 V –250 –100 –40 μA Quasi-Resonant Operation Threshold Voltage 1 VOCPBD(TH1) VOCP/BD falling 0.28 0.40 0.52 V Quasi-Resonant Operation Threshold Voltage 2 VOCPBD(TH2) VOCP/BD rising OCP/BD Terminal Outflow Current IOCPBD 0.67 0.80 0.93 V VFB rising 1.32 1.45 1.58 V IFB(ON) VFB = 1.6 V 600 1000 1400 μA Standby Operation Start Voltage VCC(S) VCC = 0→15 V, VFB = 1.6 V 10.3 11.2 12.1 V Standby Operation Start Voltage Interval VCC(SK) VCC(SK) = VCC(S) – VCC(OFF) 1.10 1.35 1.65 V Standby Non-Operation Circuit Current ICC(S) VCC = 10.2 V, VFB = 1.6 V – 20 56 μA FB Terminal Inflow Current, Standby Operation IFB(S) VCC = 10.2 V, VFB = 1.6 V – 4 14 μA FB Terminal Threshold Voltage, Standby Operation VFB(S) VCC = 15 V, VFB rising 0.55 1.10 1.50 V Minimum On Time tON(MIN) 0.75 1.15 1.55 μs FB Terminal Threshold Voltage VFB(OFF) FB Terminal Inflow Current (Normal Operation) Standby Operation Protection Operation Maximum On Time tON(MAX) 27.5 32.5 39.0 μs Overload Protection Operation Threshold Voltage VSSOLP(OLP) 4.0 4.9 5.8 V Overload Protection Operation Charging Current ISSOLP(OLP) VSS/OLP = 2.5 V –16 –11 –6 μA VCC(OVP) VCC = 0→30 V 25.5 27.7 29.9 V ICC(H) VCC(OFF) – 0.3 V Overvoltage Protection Operation Voltage Latch Circuit Holding Current2 Latch Circuit Release Voltage2 VCC(La.OFF) VCC = 30→6 V, OVP operating – 45 140 μA 6.0 7.2 8.5 V – V μA ELECTRICAL CHARACTERISTICS for MOSFET, valid at TA = 25°C, unless otherwise specified Drain-to-Source Breakdown Voltage Drain Leakage Current VDSS IDSS = 300 μA 450 – IDSS VDSSS = 450 V – – 300 IDS = 4.0 A – – 0.189 Ω – – 700 ns – – 0.99 °C/W On Resistance RDS(on) Switching Time tf Thermal Resistance Rθch-F Channel to internal frame 1Current polarity with respect to the IC: positive current indicates current sink at the terminal named, negative current indicates source at the terminal named. 2The latch circuit means a circuit operated OVP and OLP. Allegro MicroSystems, Inc. 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 6 STR-X6729 Off-Line Quasi-Resonant Switching Regulators Packing Specifications 388 100 pieces per tray 5 trays per inner carton (Outer packing dependent on quantity) Dimensions in millimeters 137 48 364 333 177 4 inner cartons per outer carton 500 pieces maximum per inner carton 2000 pieces maximum per outer carton Dimensions in millimeters 356 137 206 2 inner cartons per outer carton 500 pieces maximum per inner carton 1000 pieces maximum per outer carton Dimensions in millimeters Allegro MicroSystems, Inc. 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 7 STR-X6729 Off-Line Quasi-Resonant Switching Regulators Package Outline Drawing, TO-3P 15.6 ±0.2 5.5±0.2 2 ±0.2 6 3.45±0.2 23 ±0.3 Branding Area Ø3.2 ±0.2 5.5±0.2 Gate Burr XXXXXXXX XXXXXXXX 3 3.3 7.0±0.5 3.35±0.1 +0.2 0.55 –0.1 5.5 REF 12.5±0.5 3.3±0.5 XXXXXXXX View A 2X 2.54±0.1 4.5 ±0.7 4X 1.27±0.1 4.5 ±0.7 Terminal dimension at lead tip Terminal dimension at lead tip +0.2 1 3 1.33 –0.1 6 4 5 2X 0.83 7 +0.2 5X 0.75 –0.1 +0.2 –0.1 5X +0.2 0.65 –0.1 +0.2 1.89 –0.1 Enlargement View A 2 0.7 0.7 Front View (Plan View) Gate burr: 0.3 mm (max.) Terminal core material: Cu Terminal treatment: Ni plating and Pb-free solder dip Leadform: 1902 Approximate weight: 6 g Dimensions in millimeters 0.7 0.7 Side View Drawing for reference only Branding codes (exact appearance at manufacturer discretion): 1st line, type: STR 2nd line, subtype: X6729 3rd line, lot: YM DD Where: Y is the last digit of the year of manufacture M is the month (1 to 9, O, N, D) DD is the 2-digit date Leadframe plating Pb-free. Device composition includes high-temperature solder (Pb >85%), which is exempted from the RoHS directive. Allegro MicroSystems, Inc. 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 8 STR-X6729 Off-Line Quasi-Resonant Switching Regulators WARNING — These devices are designed to be operated at lethal voltages and energy levels. Circuit designs that embody these components must conform with applicable safety requirements. Precautions must be taken to prevent accidental contact with power-line potentials. The use of an isolation transformer is recommended during circuit development and breadboarding. Because reliability can be affected adversely by improper storage environments and handling methods, please observe the following cautions. Cautions for Storage • Ensure that storage conditions comply with the standard temperature (5°C to 35°C) and the standard relative humidity (around 40 to 75%); avoid storage locations that experience extreme changes in temperature or humidity. • Avoid locations where dust or harmful gases are present and avoid direct sunlight. • Reinspect for rust on leads and solderability of products that have been stored for a long time. Cautions for Testing and Handling When tests are carried out during inspection testing and other standard test periods, protect the products from power surges from the testing device, shorts between adjacent products, and shorts to the heatsink. Remarks About Using Silicone Grease with a Heatsink • When silicone grease is used in mounting this product on a heatsink, it shall be applied evenly and thinly. If more silicone grease than required is applied, it may produce stress. • Coat the back surface of the product and both surfaces of the insulating plate to improve heat transfer between the product and the heatsink. • Volatile-type silicone greases may permeate the product and produce cracks after long periods of time, resulting in reduced heat radiation effect, and possibly shortening the lifetime of the product. • Our recommended silicone greases for heat radiation purposes, which will not cause any adverse effect on the product life, are indicated below: Type Suppliers G746 Shin-Etsu Chemical Co., Ltd. YG6260 Momentive Performance Materials SC102 Dow Corning Toray Silicone Co., Ltd. Heatsink Mounting Method • Torque When Tightening Mounting Screws. Thermal resistance increases when tightening torque is low, and radiation effects are decreased. When the torque is too high, the screw can strip, the heatsink can be deformed, and distortion can arise in the product frame. To avoid these problems, observe the recommended tightening torques for this product package type, TO-3P: 0.588 to 0.785 N•m (6 to 8 kgf•cm). • For effective heat transfer, the contact area between the product and the heatsink should be free from burrs and metal fragments, and the heatsink should be flat and large enough to contact over the entire side of the product, including mounting flange and exposed thermal pad, and have a minimal mounting hole to prevent possible deflection and cracking of the product case when fastened to the heatsink. Soldering • When soldering the products, please be sure to minimize the working time, within the following limits: 260±5°C 10 s 350±5°C • 3s Soldering iron should be at a distance of at least 1.5 mm from the body of the products Electrostatic Discharge • When handling the products, operator must be grounded. Grounded wrist straps worn should have at least 1 MΩ of resistance to ground to prevent shock hazard. • Workbenches where the products are handled should be grounded and be provided with conductive table and floor mats. • When using measuring equipment such as a curve tracer, the equipment should be grounded. • When soldering the products, the head of soldering irons or the solder bath must be grounded in other to prevent leak voltages generated by them from being applied to the products. • The products should always be stored and transported in our shipping containers or conductive containers, or be wrapped in aluminum foil. Recommended operation temperature • Inner frame temperature in operation TF = 115°C Allegro MicroSystems, Inc. 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 9 STR-X6729 Off-Line Quasi-Resonant Switching Regulators The products described herein are manufactured in Japan by Sanken Electric Co., Ltd. for sale by Allegro MicroSystems, Inc. Sanken and Allegro reserve the right to make, from time to time, such departures from the detail specifications as may be required to permit improvements in the performance, reliability, or manufacturability of its products. Therefore, the user is cautioned to verify that the information in this publication is current before placing any order. When using the products described herein, the applicability and suitability of such products for the intended purpose shall be reviewed at the users responsibility. Although Sanken undertakes to enhance the quality and reliability of its products, the occurrence of failure and defect of semiconductor products at a certain rate is inevitable. Users of Sanken products are requested to take, at their own risk, preventative measures including safety design of the equipment or systems against any possible injury, death, fires or damages to society due to device failure or malfunction. Sanken products listed in this publication are designed and intended for use as components in general-purpose electronic equipment or apparatus (home appliances, office equipment, telecommunication equipment, measuring equipment, etc.). Their use in any application requiring radiation hardness assurance (e.g., aerospace equipment) is not supported. When considering the use of Sanken products in applications where higher reliability is required (transportation equipment and its control systems or equipment, fire- or burglar-alarm systems, various safety devices, etc.), contact a company sales representative to discuss and obtain written confirmation of your specifications. The use of Sanken products without the written consent of Sanken in applications where extremely high reliability is required (aerospace equipment, nuclear power-control stations, life-support systems, etc.) is strictly prohibited. The information included herein is believed to be accurate and reliable. Application and operation examples described in this publication are given for reference only and Sanken and Allegro assume no responsibility for any infringement of industrial property rights, intellectual property rights, or any other rights of Sanken or Allegro or any third party that may result from its use. The contents in this document must not be transcribed or copied without Sanken’s or Allegro's written consent. Copyright ©2009 Allegro MicroSystems, Inc. This datasheet is based on Sanken datasheet SSE-23880 Allegro MicroSystems, Inc. 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 10 STR-X6729 Off-Line Quasi-Resonant Switching Regulators Worldwide Contacts Asia-Pacific China Sanken Electric Hong Kong Co., Ltd. Suite 1026, Ocean Centre, Canton Road Tsimshatsui, Kowloon, Hong Kong Tel: 852-2735-5262, Fax: 852-2735-5494 150 Beach Road, #14-03 The Gateway West Tel: 65-6291-4755, Fax: 65-6297-1744 Room 3202, Maxdo Centre, Xingyi Road 8 Changning District, Shanghai, China Tel: 86-21-5208-1177, Fax: 86-21-5208-1757 Europe Sanken Power Systems (UK) Limited Pencoed Technology Park Taiwan Sanken Electric Co., Ltd. Room 1801, 18th Floor, 88 Jung Shiau East Road Sec. 2, Taipei 100, Taiwan R.O.C. Tel: 886-2-2356-8161, Fax: 886-2-2356-8261 Japan Sanken Electric Co., Ltd. Overseas Sales Headquarters Pencoed, Bridgend CF35 5HY, United Kingdom Tel: 44-1656-869-100, Fax: 44-1656-869-162 North America United States Metropolitan Plaza Building, 1-11-1 Nishi-Ikebukuro Toshima-ku, Tokyo 171-0021, Japan Tel: 81-3-3986-6164, Fax: 81-3-3986-8637 Mirae Asset Life Building, 6F 168 Kongduk-dong, Mapo-ku Seoul 121-705, Korea Tel: 82-2-714-3700, Fax: 82-2-3272-2145 Sanken Electric Singapore Pte. Ltd. Singapore 189720 Sanken Electric (Shanghai) Co., Ltd. Korea Sanken Electric Korea Co., Ltd. Singapore Allegro MicroSystems, Inc. 115 Northeast Cutoff Worcester, Massachusetts 01606, U.S.A. Tel: 1-508-853-5000, Fax: 1-508-853-7895 Allegro MicroSystems, Inc. 14 Hughes Street, Suite B105 Irvine, California 92618, U.S.A. Tel: 1-949-460-2003, Fax: 1-949-460-7837 Allegro MicroSystems, Inc. 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 11