Off-Line Quasi-Resonant Switching Regulators

Transcription

1 Features and Benefits TO 22F 7L package Lead (Pb) free compliance The built-in startup circuit reduces the number of external components and lowers standby power consumption Multi-mode control allows high efficiency operation across the full range of loads Auto burst oscillation mode for standby mode, for improving low standby power at no load: input power < 3 mw at VAC and < mw at 23 VAC Bottom-skip mode minimizes switching loss at medium to low loads Internal MOSFET V DSS (min) is 8 V Internal MOSFET R DS(on) (max) 3. Ω (), 2.2 Ω (STR-Y676) or.7 Ω () Built-in soft start function reduces stress applied to the incorporated power MOSFET and peripheral components Step-on burst oscillation minimizes transformer audible noise Built-in leading edge blanking (LEB) function eliminates Continued on the next page Description The, each comprise a power MOSFET and a multi-functional monolithic integrated circuit (MIC) controller designed for controlling switch mode power supplies. The quasi-resonant mode of operation, coupled with the bottom-skip function, allows high efficiency and low noise at low to high operational levels, while burst oscillation mode ensures minimum power consumption at standby. In order to sustain low power consumption under low load and in standby mode, the controller has built-in startup and standby circuits. This enables output power for the up to W with universal input or 8 W with a 38 VDC input, STR-Y676 up to 7 W with universal input or 2 W with a 38 VDC input and for the up to 8 W with universal input or 4 W with a 38 VDC input. The compact 7-pin full mold package (TO22F-7L) reduces board space by requiring a minimum of external components, thus simplifying circuit design. This IC, including various protection functions, is an excellent choice for standardized, compact power supplies. Package: 7-Pin TO-22F Not to scale Typical Application VAC C T D2 PC R4 V OUT P S C R Error Amp D R2 3 D/ST STR-Y67 VCC C2 DZBD D GND C V Controller BD Chip (MIC) 6 FB/ OLP S/OCP NF GND R3 ROCP C3 C4 PC C BD RBD R BD2 The NF pin (No. 7) should be connected to the GND pin (No. 4), which should be at a stable ground potential, to ensure stability of operation.

2 Features and Benefits (continued) external filter components Built-in Bias Assist function enables stable startup operation V CC operational range expanded Internal power MOSFET is avalanche energy guaranteed; twochip structure *Latched shutoff means the output is kept in a shutoff mode for protection, until reset. Protection functions Overcurrent protection (OCP): pulse by pulse basis, low dependence on input voltage Overload protection (OLP): latched shutoff* Overvoltage protection (OVP): latched shutoff* Maximum on-time limitation Thermal shutdown protection (TSD): latched shutoff* Selection Guide Part Number V DSS (min) (V) R DS(on) (max) (Ω) 3. STR-Y Package TO-22F Packing pieces per tube 2

3 Absolute Maximum Ratings Unless specifically noted, T A = 2 C and V CC = 2 V Characteristic Symbol Notes Pins Rating Unit Drain Current I DPEAK STR-Y676 Single pulse A 6.7 A. A Maximum Switching Current I DMAX STR-Y676 T A = 2 C to 2 C A 6.7 A. A Single Pulse Avalanche Energy 2 E AS STR-Y676 Single pulse, V DD = 99 V, L= 2 mh, I LPEAK = 2.3 A Single pulse, V DD = 99 V, L= 2 mh, I LPEAK = 2.6 A 2 6 mj 77 mj Single pulse, V DD = 99 V, L= 2 mh, I LPEAK = 3.2 A 6 mj Input Voltage in Control Part (MIC) V CC V Startup (D/ST) Pin Voltage V STARTUP 4. to V DSS V OCP Pin Voltage V OCP to 6. V FB Pin Voltage V FB 4.3 to 7. V FB Pin Sink Current 3 I FB 4. ma BD Pin Voltage V BD to 6. V 9.9 W Power Dissipation in MOSFET 4 P D STR-Y676 With an infinite heatsink W 23.6 W Without heatsink 2.8 W Power Dissipation in Control Part (MIC) P D2.8 W Recommended internal frame temperature Internal Frame Temperature in Operation T F is T F = C (max). 2 to C Operating Ambient Temperature T OP 2 to C Storage Temperature T stg 4 to 2 C Channel Temperature T ch C Refer to MOSFET Safe Operating Area Curve. 2 Refer to MOSFET Avalanche Energy Derating Coefficient Curve. 3 The polarity value for current specifies a sink as "+," and a source as, referencing the IC. 4Refer to MOSFET Temperature versus Power Dissipation Curve. 3

4 Functional Block Diagram STR-Y67 MIC D/ST 3 Startup VCC UVLO DRV Reg/Iconst 7 NF Latch OSC Logic OCP/BS FB/STB OLP S/OCP FB/OLP 2 4 GND BD BD 6 Pin List Table Name Number Function D/ST MOSFET drain and Startup circuit input 2 S/OCP MOSFET source and overcurrent detection signal input 3 VCC Control circuit power supply input 4 GND Ground FB/OLP 6 BD 7 NF Constant Voltage Control signal input, Standby control, and overload detection signal input Bottom Detection signal input, Input Compensation detection signal input For stable operation, connect to GND pin, using the shortest possible path 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, T A, of 2 C, unless oth er wise stated. 4

5 Electrical Characteristics of Control Part (MIC) Unless specifically noted, T A = 2 C and V CC = 2 V Characteristic Symbol Test Conditions Pins Min. Typ. Max. Unit Power Supply Startup Operation Operation Start Voltage V CC(ON) V Operation Stop Voltage V CC(OFF) V Circuit Current in Operation I CC(ON) ma Circuit Current in Non-Operation I CC(OFF) V CC = 3 V μa Startup Circuit Operation Voltage V START(ON) V Startup Current I CC(STARTUP) V CC = 3 V ma Startup Current Supply Threshold Voltage V CC(BIAS) V Operation Frequency f OSC khz Soft Start Operation Duration t SS 4 6. ms Normal Operation Bottom-Skip Operation Threshold Voltage V OCP(BS) V Bottom-Skip Operation Threshold Voltage 2 V OCP(BS2) V Quasi-Resonant Operation Threshold Voltage 2 V BD(TH) V Quasi-Resonant Operation Threshold Voltage 2 2 V BD(TH2) V Maximum Feedback Current I FB(MAX) μa Stand-by Operation Standby Operation Threshold Voltage V FB(STBOP) V Protected Operation Maximum On-Time t ON(MAX) μs Leading Edge Blanking Time t ON(LEB) STR-Y ns 47 ns 4 ns Overcurrent Detection Threshold Voltage (Normal Operation) V OCP(H) V BD = V V Overcurrent Detection Threshold Voltage (Input Compensation in V OCP(L) V BD = 3 V V Operation) Overcurrent Detection Threshold Voltage (Latched shutoff) 3 V OCP(La.OFF) V Continued on the next page

6 Electrical Characteristics of Control Part (MIC) (Continued) Unless specifically noted, T A = 2 C and V CC = 2 V Characteristic Symbol Test Conditions Pins Min. Typ. Max. Unit BD Pin Source Current I BD(O) μa OLP Bias Current I FB(OLP) 4 μa OLP Threshold Voltage V FB(OLP) V OVP Threshold Voltage V CC(OVP) V FB Pin Maximum Voltage in Feedback Operation V FB(MAX) V Thermal Shut Down Temperature T J(TSD) 3 C Note: The polarity value for current specifies a sink as "+," and a source as, referencing the IC. The relation of V CC(BIAS) > V CC(OFF) is maintained. 2 The relation of V BD(TH) > V BD(TH2) is maintained in each product. 2 The latch circuit means a circuit operated OVP, OLP, OCP (latch-off), or TSD. Electrical Characteristics of MOSFET Unless specifically noted, T A = 2 C and V CC = 2 V Characteristic Symbol Test Conditions Pins Min. Typ. Max. Unit Voltage Between Drain and Source V DSS 2 8 V Drain Leakage Current I DSS 2 3 μa On-Resistance R DS(on) STR-Y Ω 2 3. Ω 2.7 Ω Switching Time t f STR-Y ns 2 ns 3 ns Thermal Resistance R θch-f Between a channel C/W STR-Y676 of the MOSFET and the internal C/W leadframe C/W 6

7 Characteristic Performance () S. O. A. Temperature Derating Coefficient Curve Safe Operating Area Temperature Derating Coefficient (%) EAS Temperature Derating Coefficient (%) MOSFET Avalanche Energy Derating Coefficient Curve Channel Temperature, Tch ( C) Channel Temperature, Tch ( C) Drain Current, ID (A) MOSFET Temperature versus Power Dissipation Curve Allowable Power Dissipation, PD (W) MOSFET Safe Operating Area Curve. To use this graph, apply the S.O.A temperature derating coefficient taken from the graph at the left. Drain-to-Source Voltage, VDS (V) Drain current limited by on-resistance T A = 2 C Single pulse 9.9 ms.8 Without heatsink. ms With infinite heatsink Ambient Temperature, TA ( C) Transient Thermal Resistance, Rθch-c ( C/W).. Transient Thermal Resistance Curve Time (s) 7

8 Characteristic Performance (STR-Y676) S. O. A. Temperature Derating Coefficient Curve Safe Operating Area Temperature Derating Coefficient (%) EAS Temperature Derating Coefficient (%) MOSFET Avalanche Energy Derating Coefficient Curve Channel Temperature, Tch ( C) Channel Temperature, Tch ( C) Drain Current, ID (A) MOSFET Temperature versus Power Dissipation Curve Allowable Power Dissipation, PD (W) MOSFET Safe Operating Area Curve. To use this graph, apply the S.O.A temperature derating coefficient taken from the graph at the left. Drain-to-Source Voltage, VDS (V) Drain current limited by on-resistance ms T A = 2 C Single pulse Without heatsink. ms With infinite heatsink Ambient Temperature, TA ( C) Transient Thermal Resistance, Rθch-c ( C/W).. Transient Thermal Resistance Curve Time (s) 8

9 Characteristic Performance () MOSFET Safe Operating Area Curve S. O. A. Temperature Derating Coefficient Curve Safe Operating Area Temperature Derating Coefficient (%) EAS Temperature Derating Coefficient (%) MOSFET Avalanche Energy Derating Coefficient Curve Channel Temperature, Tch ( C) Channel Temperature, Tch ( C) Drain Current, ID (A) MOSFET Temperature versus Power Dissipation Curve Allowable Power Dissipation, PD (W) To use this graph, apply the S.O.A temperature derating coefficient taken from the graph at the left. Drain-to-Source Voltage, VDS (V) Drain current limited by on-resistance T A = 2 C Single pulse 23.6 ms.8 Without heatsink. ms With infinite heatsink Ambient Temperature, TA ( C) Transient Thermal Resistance, Rθch-c ( C/W).. Transient Thermal Resistance Curve Time (s) 9

10 Package Outline Drawing ±.2 Gate burr ± ±.2 Ø3.2 ±.2 (.6) STR a b ±.3 (.) 2.6±. (At base of pin) ±. ±. ± ±..4 R-end R-end 2 ±. P.7±. =.8±. (At base of pin) ±.6 (At tip of pin).8±.6 (At tip of pin) Front view Side view Unit: mm Package: TO-22F (Sanken leadform #3) Leadframe material: Cu Pin treatment: Solder dip Weight: Approximately.4 g "Gate Burr" shows area where.3 mm (max) gate burr may be present Pin treatment Pb-free. Device composition compliant with the RoHS directive. a: Part # Y676x b: Lot number st letter: Last digit of year 2 nd letter: Month Jan to September: Numeric October: O November: N December: D 3 rd and 4 th letter: Date to 3: Numeric th letter: Internal use control number

11 Packing Specifications 4 ± ± ANTISTATIC (.9) ± ±.3 2. Tube dimensions (mm) pieces per tube 8 Carton dimensions (mm) 36 tubes per carton (maximum) 8 pieces maximum per carton

12 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 ( C to 3 C) and the standard relative humidity (around 4% to 7%); 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 the product pins, and wrong connections. 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 excess stress. Volatile-type silicone greases may crack after long periods of time, resulting in reduced heat radiation effect. Silicone grease with low consistency (hard grease) may cause cracks in the mold resin when screwing the product to a heatsink. 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. YG626 MOMENTIVE Performance Materials, Inc. SC2 Dow Corning Toray Co., Ltd. Heatsink Assembly Attachment torque should be in the range.88 to.78 N m (6 to 8 kgf cm). Soldering The leadframe temperature should never exceed T F = C(max). When soldering the products, please be sure to minimize the working time, within the following limits: 26± C s 3± C 3 s (solder iron) Soldering iron should be at a distance of at least 2. mm from the body of the products. Electrostatic Discharge When handling the products, the operator must be grounded. Grounded wrist straps worn should have at least MΩ of resistance from the operator to ground to prevent shock hazard, and it should be placed near the operator. 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 Sanken shipping containers or conductive containers, or be wrapped in aluminum foil. 2

13 The products described herein are manufactured in Ja pan by Sanken Electric Co., Ltd. for sale by Sanken and Allegro reserve the right to make, from time to time, such de par tures from the detail spec i fi ca tions as may be re quired to per mit improve ments in the per for mance, reliability, or manufacturability of its prod ucts. Therefore, the user is cau tioned to verify that the in for ma tion in this publication is current before placing any order. When using the products described herein, the ap pli ca bil i ty and suit abil i ty 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 prod ucts, the occurrence of failure and defect of semiconductor products at a certain rate is in ev i ta ble. 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 equip ment or apparatus (home ap pli anc es, office equipment, tele com mu ni ca tion equipment, measuring equipment, etc.). Their use in any application requiring radiation hardness assurance (e.g., aero space equipment) is not supported. When considering the use of Sanken products in ap pli ca tions where higher reliability is re quired (transportation equipment and its control systems or equip ment, 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 ex treme ly high reliability is required (aerospace equipment, nuclear power-control stations, life-support systems, etc.) is strictly prohibited. The information in clud ed herein is believed to be accurate and reliable. Ap pli ca tion and operation examples described in this publication are given for reference only and Sanken and Allegro assume no re spon si bil i ty for any in fringe ment of in dus tri al 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 22 3