International Rectifier - The Power Management Leader 产 品 系 列 销 售 支 持 技 术 资 料 设 计 支 持 技 术 支 持 中 心 产品型号搜索 新闻发布 产品应用 IR 针对非隔离式驱动器应用推出高电压 IRS2980 LEDrivIR IC 可提升性能与成本效益 2011年10月28日 全球功率半导体和管理方案领导厂商国际整流器公司 公司资料 (International Rectifier，简称IR) 近日推出 IRS2980 新闻发布 IR 展览会 产品宣传资料 杂志广告 技术文章 技术支持中心 高电压降压稳压器控制IC，适合 LED 灯泡替换、LED 灯 管照明及其它非隔离式 LED 驱动器应用。 IRS2980 是高电压 LEDrivIR IC 系列的首款产品，额定 值为 600V，使用滞后平均电流模式控制来实现精准的电 流调节。新款 LED 降压驱动器搭载附有高电压内部稳压 器和高侧电流感应功能的低侧 MOSFET 驱动器。转换器可兼容电子脉冲宽度调制 (PWM) 调光，电流控 制范围为0% 至100%。 IR 亚太区销售副总裁潘大伟表示：“固态照明产业发展迅速，因此对于能够为高亮度及高功率LED提供 恒流输出的低成本驱动器电子器件的需求与日俱增。与其它适合非隔离式LED 驱动器应用的解决方案相 比，全新的 IRS2980 LEDrivIR IC 能够提供更低系统成本和更高性能。” 采用 SO-8 封装的 IRS2980 使用整合了最新高压电平位移和终端技术的 IR 先进高电压 IC 加工工 艺，提供卓越的电气过应力保护和更高的现场可靠性。新器件还具有其他新功能与强化性能。 产品规格 器件编号 IRS2980SPBF 交流 -- 直流 家用电器 汽车 直流 -- 直流 照明 网络通信 封装 电压 VTH Io 最高频率 SO8 600 V 0.5V +/- 80/260mA 150kHz 相关数据资料和应用说明，以及采用 IRS2980DS 的参考设计IRPLLED7，请浏览 IR 的网站 www.irf.com。 http://www.irf.com.cn/irfsite/news/2011/323.asp?utm_source=supplyFrame&utm_medium=Ads[2012-6-14 6:21:28] 宇航/高可靠性 音响 桌上电脑/服务器 企业用电源 电机驱动 便携产品 International Rectifier - The Power Management Leader 有关产品现已接受批量订单。新器件不含铅，也符合电子产品有害物质管制规定 (RoHS) 。 专利和商标 LEDrivIR? 是国际整流器公司 (International Rectifier Corporation) 的商标，IR? 是国际整流器 公司的注册商标。文中所提及其它产品名称均为对应持有人所有的商标。 IR简介 国际整流器公司 (简称 IR，纽约证交所代号 IRF) 是全球功率半导体和管理方案领导厂商。IR 的模拟 及混合信号集成电路、先进电路器件、集成功率系统和器件广泛应用于驱动高性能计算设备及降低电机 的能耗 (电机是全球最大耗能设备) ，是众多国际知名厂商开发下一代计算机、节能电器、照明设备、 汽车、卫星系统、宇航及国防系统的电源管理基准。 IR 成立于 1947 年，总部设在美国洛杉矶，在二十个国家设有办事处。IR 全球网站：www.irf.com， 中国网站：www.irf.com.cn。 新 闻 发 布 索 引 产品系列 产品目录 参数搜索 HEXFET 功率 MOSFET 集成电路 栅驱动器IC IGBTs 微电子继电器 SupIRBuck XPhase 芯片产品 销售支持 技术资料 技术支持中心 如何购买 产品搜索 搜索替代产品 产品变更通知 制造厂 联系 IR 中国 IR 中国代理商 目录元件经销商 应用训练指南 应用笔记 设计提示 封装信息 质量与可靠性报告 技术文章 技术支持 设计工具 SupIRBuck设计工具 同步整流 IGBT选择工具 总线转换器 照明镇流器没计 IPM仿真器 MCE编译器 功率因素校正 Point of Load SyncBuck MOSFET工具 参考设计 模型 搜寻FAQ 在线提问 问题追踪 International Sites: | English | Korean ??? | Japanese 日本語 | 京ICP备05048912号 About International Rectifier | Contact Us | Privacy ? 1995-2009 International Rectifier http://www.irf.com.cn/irfsite/news/2011/323.asp?utm_source=supplyFrame&utm_medium=Ads[2012-6-14 6:21:28] January 20th, 2012 IRS2980S LED DRIVER CONTROL IC Product Summary IC Features • • • • • • • • Dimming LED driver controller Hysteretic Current Regulation Closed-loop LED current dimming control Analog/PWM Dimming Input Internal High Voltage Regulator Internal 15.6V zener clamp diode on Vcc Micropower startup (250μA) Latch immunity and ESD protection • • • Buck VOFFSET (breakdown) 600 V VOUT VCC IO+ & IO- (typical) 180mA & 260mA Package Types LED Driver System Features • • • Topology Single chip dimming solution Simple LED current dimming control method No external protection circuits required (fully internal) Low external component count Easy to use for fast design cycle time Increased manufacturability and reliability SO8 Typical applications • • LED incandescent/CFL replacement lamps LED driver module Typical Connection Diagram IRS2980 www.irf.com © 2011 International Rectifier 1 IRS2980S Table of Contents Page Description 3 Block Diagram 3 Qualification Information 4 Absolute Maximum Ratings 5 Recommended Operating Conditions 6 Electrical Characteristics 7 Input/Output Pin Equivalent Circuit Diagram 9 Lead Definitions 10 Lead Assignments 10 Application Information and Additional Details 11 Package Details 15 Tape and Reel Details 16 Part Marking Information 17 Ordering Information 18 www.irf.com © 2011 International Rectifier 2 IRS2980S Description The IRS2980S utilizes International Rectifier's control and high-voltage technologies to realize a simple, high-performance Buck LED driver solution. This solution is based on hysteretic output current regulation typically operating from 25 kHz to 120 kHz. Frequency and duty cycle vary to maintain a tightly regulated average output current over variations in line and load. Output current ripple will depend on inductor selection in conjunction with input and output voltages as well as output current and component selection. The IRS2980S uses a unique floating high side differential current sense and level shift scheme allowing hysteretic operation with a low side switching MOSFET optimizing size and cost. In addition, the IRS2980S includes a high voltage regulator able to operate up to 450V eliminating the need for an external VCC supply. A PWM dimming interface is also included that can be controlled from a 0 to 2V analog or 3.3 or 5V logic control signal able to operate up to 1kHz offering brightness control from 0 to 100%. A programmable on board PWM oscillator is used with DC dimming control. Block Diagram HV 1 5 ADIM 6 RAMP 7 OUT 4 COM 0.5V VCC Ref CS 8 2V 0.2V 15.6V VS 2 High Side Well 1V REGULATOR UVLO VCC VCC 3 NOISE FILTER + MAXIMUM FREQUENCY TIMING 15.6V www.irf.com © 2011 International Rectifier 3 IRS2980S † Qualification Information Qualification Level Moisture Sensitivity Level Machine Model ESD Human Body Model IC Latch-Up Test RoHS Compliant Industrial†† Comments: This family of ICs has passed JEDEC’s Industrial qualification. IR’s Consumer qualification level is granted by extension of the higher Industrial level. MSL2††† (per IPC/JEDEC J-STD-020C) Class B (per JEDEC standard JESD22-A115) Class 2 (per EIA/JEDEC standard EIA/JESD22-A114) Class I, Level A (per JESD78) Yes † †† Qualification standards can be found at International Rectifier’s web site http://www.irf.com/ Higher qualification ratings may be available should the user have such requirements. Please contact your International Rectifier sales representative for further information. ††† Higher MSL ratings may be available for the specific package types listed here. Please contact your International Rectifier sales representative for further information. www.irf.com © 2011 International Rectifier 4 IRS2980S Absolute Maximum Ratings Absolute Maximum Ratings indicate sustained limits beyond which damage to the device may occur. All voltage parameters are absolute voltages referenced to COM; all currents are defined positive into any lead. The Thermal Resistance and Power Dissipation ratings are measured under board mounted and still air conditions. Symbol Definition † Min. Max. Units VHV High Voltage Input -0.3 450 VOUT Low-Side Output Voltage -0.3 VCC + 0.3 VADIM VRAMP DIM Input Voltage -0.3 RAMP Input Voltage -0.3 VCC + 0.3 VCC + 0.3 --- 20 -500 500 --- 0.625 W ºC/W †† ICC PD Supply Current Maximum allowable current at OUT due to external power transistor Miller effect. ††† Maximum Power Dissipation @ TA ≤ +25ºC RθJA Thermal Resistance, Junction to Ambient --- 128 TJ Junction Temperature -55 150 TS Storage Temperature -55 150 TL Lead Temperature (Soldering, 10 seconds) --- 300 IOMAX V mA ºC † The IRS2980S uses an HVIC process capable of withstanding up to 600V, however the internal regulator maximum input voltage rating is limited to 450V maximum due to package power dissipation. The device can withstand transient voltages up to 600V for short periods. †† This IC contains a zener clamp structure between the chip VCC and COM which has a nominal breakdown voltage of 15.6V. This supply pin should not be driven by a DC, low impedance power source greater than the VCLAMP specified in the Electrical Characteristics section. ††† Power dissipation is dependent on VHV and switching frequency. In order to limit device temperature rise some thermal relief may be required in the form of copper on the PCB located under and around the device. Alternatively a small heat sink may be attached to the top of the device. Thermally conductive potting compounds can also provide excellent heat transfer. www.irf.com © 2011 International Rectifier 5 IRS2980S Recommended Operating Conditions For proper operation the device should be used within the recommended conditions. Symbol † Definition † Min. Max. Units VHV VCC ICC High Voltage Input Supply Voltage Supply Current 0 10.0 --- 375 VCLAMP 5 mA VRAMP VENN Pin Voltage 0 6 V VADIM VENN Pin Voltage 0 6 V VENN VENN Pin Voltage 0 6 V TJ Junction Temperature -40 125 ºC V Operation above this voltage level and below 450V is possible with sufficient heat sinking. www.irf.com © 2011 International Rectifier 6 IRS2980S Electrical Characteristics VHV=100V, VCC=14V, CVCC=0.1μF, CHVS=22nF, and TA = 25°C unless otherwise specified. The output voltage and current (VO and IO) parameters are referenced to COM and are applicable to OUT. Symbol Definition Min Typ Max Units Test Conditions 14.6 15.6 16.6 V ICC = 10mA --- 250 --- µA VCC = 6V Low Voltage Supply Characteristics VCLAMP VCC Zener Clamp Voltage IQCCUV Micropower Startup VCC Supply Current High Voltage Regulator Characteristics VCCREG VCC Regulation Voltage 8.9 9.9 10.9 V ICC = 1mA IREG_MAX Maximum Regulator Current --- 3 5 mA Vcc = 0V † --- 60 --- V VHVS+ High Side UVLO Positive Threshold 8.3 9.3 10.3 VHVS- High Side UVLO Negative Threshold 6.3 7.3 8.3 --- 150 --- kHz --- 100 --- % --- 0.5 --- V --- 100 --- mV RAMP Pin Charging Current --- 15 --- µA VRAMP+ RAMP Pin Shutdown Threshold --- 2.0 --- VRAMP- RAMP Pin Re-start Threshold --- 0.2 --- Dimming Duty Cycle 0 VHVMIN Minimum HV required for regulator High Side Voltage Supply Characteristics V Control Characteristics fMAX Maximum Output Frequency dMAX Buck Duty Cycle VCS VCS-HYS Current Regulation Threshold Current Regulation Hysteresis †† Dimming Characteristics IRAMP dPWM 100 % † VCC can be supplied from an alternative source for the IRS2980S to operate with bus voltages below this level. †† Various tolerances on VCS are available upon request www.irf.com © 2011 International Rectifier 7 IRS2980S Electrical Characteristics VHV=100V, VCC= 14V, CVCC=0.1µF, CHVS=22nF and TA = 25°C unless otherwise specified. The output voltage and current (VO and IO) parameters are referenced to COM and are applicable to OUT. Symbol Definition Min Typ Max Units Test Conditions Gate Driver Output Characteristics (OUT) VOH High-Level Output Voltage --- VCC --- IO = 0A VOL Low-Level Output Voltage --- COM --- IO = 0A --- IO = 0A, VCC ≤ 8.0V VOL_UV --- UV-Mode Output Voltage COM tr Output Rise Time --- 120 220 tf Output Fall Time --- 50 80 IO+ Output source current --- 180 --- IO- Output sink current --- 260 --- www.irf.com ns mA © 2011 International Rectifier 8 IRS2980S I/O Pin Equivalent Circuit Diagrams www.irf.com © 2011 International Rectifier 9 IRS2980S Lead Definitions Pin # Symbol Description 1 HV High Voltage Bus 2 VS High Side Floating Supply Return 3 VCC VCC Supply 4 COM Ground / Common 5 ADIM Linear / Analog Dimming Input 6 RAMP Ramp Waveform for Analog Dimming 7 OUT 8 CS Gate Drive Output Load Current Sense Lead Assignments 1 VS 2 VCC 3 COM 4 IRS2980 HV www.irf.com 8 CS 7 OUT 6 RAMP 5 ADIM © 2011 International Rectifier 10 IRS2980S Application Information and Additional Details operating conditions imposed by the input and output voltages, output current and inductor value. The IRS2980S is primarily intended for use in Buck LED drivers operating with average current regulation using hysteretic control. The circuit topology uses a low side MOSFET referenced to the 0V bus driven by a low side gate driver circuit within the IRS2980S and an additional fast recovery freewheeling diode. In order to minimize switching losses the reverse recovery time of this diode should be no more than 35nS. The MOSFET should be selected for low capacitance to reduce switching losses and low gate charge (less than 25nC is recommended) to minimize gate drive current. The LED load is referenced to the DC bus and not 0V. The IRS2980S incorporates floating high side current sense inputs allowing the LED current to be sensed both when the MOSFET is switched on and off. This enables hysteretic operation, switching the MOSFET off when the current rises above an upper threshold and off when the current falls below a lower threshold. The current sense threshold Vcs is nominally 500mV with approximately 100mV of hysteresis making the upper limit Vcs+50mV and the lower limit Vcs-50mV. Some overshoot typically occurs due to propagation delays and a small undershoot is also possible. These vary depending on di/dt of the ripple current, which is a function of input and output voltage, inductor value and frequency as well as RC filter values (RF and CF). The average current is maintained at approximately the midpoint over a wide input and output voltage range due to the inherent accuracy of hysteretic control. The LED output current is set by selecting the value of the current sense resistor RCS. This is determined by the formula: The following diagram shows the rise and fall of the LED current as the MOSFET switches on and off: RCS = Figure 1: MOSFET gate drive and inductor/LED current. The following formulae model the operation of the IRS2980S based Buck LED driver: t on ≈ Q 0.2 ⋅ L ⋅ I LED + RF ⋅ C F + G + t dr VBUS _ DC − VLED 0.18 t off ≈ Q 0.2 ⋅ L ⋅ I LED + RF ⋅ C F + G + t df VLED 0.26 f SW = d= 1 (switching frequency) t on + t off t on (duty cycle) t on + t off Where, VCS I LED RF and CF are the current sense filter components, L is the inductor value, QG is the MOSFET gate charge, tdr and tdf are propagation delays (These values vary depending on circuit conditions, tdr decreases with input voltage. tdf is normally negligible. For a first order approximation these terms may be ignored.) Where ILED is the average LED output current. The peak to peak ripple ∆ILED will be 20% of the average LED current ILED due to the hysteretic operation plus some additional ripple due to circuit delays. These are caused mainly by the current sense filter and MOSFET gate drive. Since the IRS2980S uses hysteretic current control to switch the Buck MOSFET on and off, the LED current (which is equal to the inductor current) is maintained between upper and lower thresholds. Because of this the switching frequency and duty cycle vary to meet the www.irf.com © 2011 International Rectifier 11 IRS2980S pin of the IRS2980S is rated up to 450V, the actual maximum voltage that can be applied is limited by the by the power dissipation of the IC. The internal VCC regulator is recommended for use up to 200VDC or with a passive valley fill PFC circuit operating from up to 250VAC input. It can be operated at higher voltages only with sufficient heat sinking. Operating frequency and duty cycle will vary when there is ripple in the DC bus voltage. For example where a passive valley fill circuit is used for power factor correction (PFC) the LED current will be regulated dynamically by constantly changing frequency and duty cycle to maintain a constant average. Current Sense Filter Selection The recommended values for RF and CF are 100Ohms and 1nF. This is sufficient to prevent instability due to switching noise appearing at the current sense input. These values have negligible effect on the frequency and ripple. In a test application using a 3.3mH inductor to drive a 17.5V LED panel, the output current varied from 338mA to 347mA (2.7%) over a DC voltage input range of 40V to 200V. A resistor (RG) between the gate driver output and the gate of the power MOSFETs is also recommended to reduce switching transients by reducing dv/dt. A value of 10Ohms is recommended, however this can be increased to reduce noise if required. Filter values may be increased in order to lower the running frequency without increasing inductor size. This results in higher current ripple and higher current change over input voltage variations. This may be an acceptable compromise depending on the application specification. Figure 2: Passive valley fill PFC circuit Frequency Limiter The switching frequency of the IRS2980S is internally limited to approximately 150 kHz (fMAX). The IRS2980S is designed for use below this frequency in order to limit current consumption in the VCC and floating high side bias supplies. This is necessary because the IRS2980S uses internal regulators to supply these voltages, which can supply only a limited current. This restriction is acceptable in most LED driver applications. Where higher frequency operation is needed the IRS25401/11 is recommended. Figure 3: Passive valley fill PFC bus voltage (blue) and line input current (red) waveforms. The VCC current (ICC) drawn by the IRS2980S can be estimated from the following formula: I CC ≈ 1mA + QG ⋅ f SW High Voltage Regulator The IRS2980S includes a high voltage regulator to supply VCC from the DC input bus voltage. This eliminates the need for external VCC supply circuitry. A VCC capacitor of 1uF is recommended for reliable startup and smooth operation. The IRS2980S may shut down if CVCC is not present or too small. If necessary the internal regulator may also be bypassed by supplying an external DC supply from 14V to 15V to the VCC pin. Although the HV Therefore power dissipation due to the high voltage regulator can be calculated as: PREG = VBUS _ DC _ AV ⋅ I CC Floating Differential Current Sense The floating high side current sense incorporated in the IRS2980S is able to operate up to 450V and withstand voltage surges up to 600V. An internal bias supply is derived between the HV and VS www.irf.com © 2011 International Rectifier 12 IRS2980S pins by a 1mA current source pulling down on VS so that a supply voltage is produced across the external capacitor CHVS to supply the high side circuitry. A value of 22nF is recommended for CHVS. The internal bias supply also dissipates some power, which can be calculated from the formula: PBIAS = (VBUS _ DC _ AV − 10) ⋅1mA In order for the high side current sense circuitry to function, a minimum bus voltage of 30V is required to provide adequate bias supply current and standoff voltage. Figure 4: Thermal relief example In addition if the IRS2980S is used in an application where the circuit is encapsulated in thermally conductive filler the die temperature rise is also greatly reduced. Figure 4 shows an example of thermal relief placed around the IRS2980S in a high voltage application. The top side copper layer is shown as red and the bottom side is blue. With thermal relief ∆T becomes: Thermal Considerations Since the IRS2980S dissipates some power during normal operation, temperature rise of the IC die must be considered as part of the design process. The SO8 IC package has a maximum power rating (PD) of 625mW, therefore the sum of PREG and PBIAS should not exceed this value. The junction temperature should remain below 125°C to ensure operation within specifications. The junction temperature is normally 10°C above the case temperature for an SO8 package therefore the case temperature should not exceed 115°C at maximum ambient. The junction to ambient thermal resistance of the package (RθJA) is 128°C/W. This would give an 80°C temperature rise without any thermal relief at the maximum PD value of 625mW. ⎡ RθJA ⋅ RθHS ⎤ ΔT = PD ⋅ ⎢ ⎣ RθJA + RθHS ⎥⎦ Where RθHS is the thermal resistance of the thermal relief area or heat sink, which will normally be lower than RθJA. Dimming The IRS2980S includes a PWM dimming oscillator that generates a linear ramp waveform at the RAMP pin with the frequency determined by an external capacitor to COM (CRAMP). A DC voltage is applied to the ADIM pin which is compared to this ramp to produce a gating signal that enables and disables the high frequency switching of the MOSFET gate drive. By varying the ADIM voltage the duty cycle is adjusted allowing brightness to be adjusted from zero to 100%. This is accomplished by operating the LED driver in burst mode and varying the duty cycle of the bursts. The LED current during dimming is shown in figure 5: ΔT = PD ⋅ RθJA In order to reduce the junction temperature rise thermal relief should be added around the IRS2980S on the PCB. With adequate thermal relief the die temperature rise can be greatly reduced. The recommended method is to place an area of copper on the opposite side of the PCB to the IC in the same position with several vias added underneath the IC to conduct heat through to the other side. www.irf.com © 2011 International Rectifier 13 IRS2980S being used in dim mode place a capacitor CDIM from the ADIM pin to COM and keep the capacitor as close to the IC as possible with the shortest possible traces. 4) If the IRS2980S is being used in non-dimming mode the RAMP pin can be connected to COM. If it is being used in dimming mode CRAMP should be located close to the IC with the shortest possible traces to the RAMP pin and COM. 5) Connect IC COM to power GND at one connection only. Do NOT route power GND through the programming components or IC COM. Figure 5: LED current during dimming. The dimming level can also be controlled from a digital input by replacing CRAMP with a 68k resistor. This sets a DC threshold at the RAMP pin to approximately 1V so that a logic level PWM dimming control signal can be applied to the ADIM pin to directly switch the output on and off. PCB Layout Guidelines Proper care should be taken when laying out a PCB board ensure correct functionality of the IRS2980S. Transients caused by high dV/dt during switching could potentially cause some false triggering of the hysteretic circuit therefore a small filter comprising RF and CF is recommended. CF should be located close to the IC pins with the trace from HV to RCS and the traces from RCS to CS through RF kept as short as possible. The 0V load return power ground should be connected to the IC COM pin and at a single point to avoid ground loops. The values of RF and CF are normally chosen to provide noise filtering without adding excessive delay to the circuit, however in some case these are deliberately made larger to lower the running frequency as this reduces switching losses and ICC current. The following guidelines should be followed during PCB board layout: 1) Place VCC supply decoupling capacitor (CVCC) as close as possible to the VCC and COM pins. 2) Place high side decoupling capacitor (CVF) as close as possible to the HV and VS pins. 3) If the IRS2980S is being used in non-dimming mode connect the ADIM pin to VCC. If it is www.irf.com © 2011 International Rectifier 14 IRS2980S Package Details www.irf.com © 2011 International Rectifier 15 IRS2980S Tape and Reel Details LOADED TAPE FEED DIRECTION A B H D F C NOTE : CONTROLLING DIM ENSION IN M M E G CARRIER TAPE DIMENSION FOR Metric Code Min Max A 7.90 8.10 B 3.90 4.10 C 11.70 12.30 D 5.45 5.55 E 6.30 6.50 F 5.10 5.30 G 1.50 n/a H 1.50 1.60 8SOICN Imperial Min Max 0.311 0.318 0.153 0.161 0.46 0.484 0.214 0.218 0.248 0.255 0.200 0.208 0.059 n/a 0.059 0.062 F D C B A E G H REEL DIMENSIONS FOR 8SOICN Metric Code Min Max A 329.60 330.25 B 20.95 21.45 C 12.80 13.20 D 1.95 2.45 E 98.00 102.00 F n/a 18.40 G 14.50 17.10 H 12.40 14.40 www.irf.com Imperial Min Max 12.976 13.001 0.824 0.844 0.503 0.519 0.767 0.096 3.858 4.015 n/a 0.724 0.570 0.673 0.488 0.566 © 2011 International Rectifier 16 IRS2980S Part Marking Information Part number IRSxxxxx Date code YWW ? Pin 1 Identifier ? MARKING CODE P Lead Free Released IR logo ? XXXX Lot Code (Prod mode – 4 digit SPN code) Assembly site code Per SCOP 200-002 Non-Lead Free Released www.irf.com © 2011 International Rectifier 17 IRS2980S Ordering Information Standard Pack Base Part Number IRS2980S Package Type SOIC8N Complete Part Number Form Quantity Tube/Bulk 95 IRS2980SPBF Tape and Reel 2500 IRS2980STRPBF The information provided in this document is believed to be accurate and reliable. However, International Rectifier assumes no responsibility for the consequences of the use of this information. International Rectifier assumes no responsibility for any infringement of patents or of other rights of third parties which may result from the use of this information. No license is granted by implication or otherwise under any patent or patent rights of International Rectifier. The specifications mentioned in this document are subject to change without notice. This document supersedes and replaces all information previously supplied. For technical support, please contact IR’s Technical Assistance Center http://www.irf.com/technical-info/ WORLD HEADQUARTERS: 233 Kansas St., El Segundo, California 90245 Tel: (310) 252-7105 www.irf.com © 2011 International Rectifier 18 IR Part Summary Page - IRS2980SPBF An LED Driver Control IC Part Search Part: IRS2980SPBF Description: An LED Driver Control IC Support Docs: Datasheet News Release Reference Design Latch immunity and ESD protection LED Driver System Features IC Features Dimming LED driver controller Hysteretic Current Regulation Closed-loop LED current dimming control Analog/PWM Dimming Input Internal High Voltage Regulator Internal 15.6V zener clamp diode on Vcc Micropower startup (250礎) Single chip dimming solution Simple LED current dimming control method No external protection circuits required (fully internal) Easy to use for fast design cycle time Increased manufacturability and reliability Long Description The IRS2980 utilizes International Rectifier's control and high-voltage technologies to realize a simple, highperformance dimming LED driver solution. This solution is based on a hysteretic topology where the high frequency AC output current is controlled by adjusting the oscillator frequency and duty cycle. Functional Block Diagram Detailed functional block diagram available in PDF Typical Connection Specifications Parameter Value https://ec.irf.com/v6/en/US/adirect/ir?cmd=catProductDetailFrame&productID=IRS2980SPBF[2012-6-14 6:22:13] Site Search IR Part Summary Page - IRS2980SPBF An LED Driver Control IC Package Circuit Offset Voltage (V) Output Source Current min (mA) Output Sink Current min (mA) PbF t r (ns) t f (ns) 8-lead SOIC LED Driver 600 180 260 Yes 120 50 Packaging Options Product ID Description Standard 1K Budgetary Pack Pricing (USD) Status An IRS2980S with Standard Packaging An IRS2980SPBF shipped IRS2980STRPBF on Tape and Reel IRS2980SPBF Qty Active 95 $0.76 1 Active 2500 $0.76 1 Package Support Docs 8-Lead SOIC Case Outline REACH Compliance RoHS/PbF Compliance IRPLLED7 90-250V AC input voltage LED Driver Featuring IRS2980S HVIC LED driver Non-isolated buck regulator 90-250V AC input voltage 0-50V DC output voltage Regulated output current of 350mA PWM dimmable Click here to display Distributor Inventory Part Search: International Sites: | Chinese 简体中文 | Korean ??? | Japanese 日本語 | About International Rectifier | Contact Us | Privacy ?1995- 2010 International Rectifier https://ec.irf.com/v6/en/US/adirect/ir?cmd=catProductDetailFrame&productID=IRS2980SPBF[2012-6-14 6:22:13] IR’s High-voltage IRS2980 LEDrivIR™ IC for Non-isolated LED Driver Applications Offers Improved Performance and Greater Cost Efficiency IR’s High-voltage IRS2980 LEDrivIR™ IC for Non-isolated LED Driver Applications Offers Improved Performance and Greater Cost Efficiency Part Search EL SEGUNDO, Calif. — International Rectifier, IR® (NYSE: IRF), a world leader in power management technology, today introduced the IRS2980 high-voltage buck regulator control IC for LED light bulb replacement, LED tube lighting and other non-isolated LED driver applications. Rated at 600 V, the IRS2980 is the first in a family of high-voltage LEDrivIR™ ICs, and utilizes hysteretic average current mode control for precise current regulation. The LED buck driver features low-side MOSFET drive with high-voltage internal regulator and high-side current sensing. The converter is compatible with electronic PWM dimming allowing for 0%-100% current control. Site Search AC-DC Appliances Automotive DC-DC Lighting NetCom A&D/HiRel Audio Desktop/Server Enterprise Power Motor Control Portables About IR Careers Contact Us Investor Relations Site Index Press Room Corporate Social Responsibility Awards Featured Articles Print Advertising Request Literature Trade Show Calendar Editorial Contacts “In the rapidly growing solid state lighting sector, there is a need for low cost driver electronics to supply constant current output to high brightness, high power LEDs. The new IRS2980 LEDrivIR™ IC offers improved performance at a lower system cost than alternative solutions for non-isolated LED driver applications,” said Peter Green, LED Group Manager, IR’s Energy Saving Products Business Unit. All News Releases New Product Releases New Catalog Additions Investor News E-Mail News RSS Feeds Available in an SO-8 package, the IRS2980 utilizes IR’s advanced high-voltage IC process which incorporates latest-generation high-voltage level-shifting and termination technology to deliver superior electrical over-stress protection and higher field reliability, in addition to other new features and enhancements. Specifications Part Number IRS2980SPBF Package Voltage VTH Io Max Frequency SO8 600 V 0.5V +/- 180/260mA 150kHz Design Tools A datasheet and application note are available on the International Rectifier website at www.irf.com. A reference design, the IRPLLED7, featuring the IRS2980DS is also available. Availability and Pricing Pricing for the IRS2980 begins at US $0.60 each in quantities of 10,000-units. The IRPLLED7 costs US $99 per kit. Production quantities are available immediately. The devices are lead free and RoHS compliant. Prices are subject to change. International Sites: | Chinese ???? | Korean ??? | Japanese ??? | http://www.irf.com/whats-new/nr111025.html[2012-6-14 6:23:03] About International Rectifier | Contact Us | Privacy ©1995- 2012 International Rectifier IR Part Summary Page - IRPLLED7 90-250VAC Offline LED Driver using LEDrivIR IRS2980 Part Search Site Search Part: IRPLLED7 Description: 90-250VAC Offline LED Driver using LEDrivIR IRS2980 Support Docs: Datasheet Application Note News Release Featured Part Datasheet IRPLLED7 90-250V AC input voltage LED Driver Featuring IRS2980S HVIC LED driver Non-isolated buck regulator 90-250V AC input voltage 0-50V DC output voltage Regulated output current of 350mA PWM dimmable Specifications Parameter Value Package Featured Part Line Input Lamps Design Kit IRS2980 90-250 VAC LED Packaging Options Product ID IRPLLED7 Description A IRPLLED7 with Standard Packaging Standard 1K Budgetary Pack Pricing (USD) Status Active 1 $125.00 Qty 1 Click here to display Distributor Inventory Part Search: International Sites: | Chinese 简体中文 | Korean ??? | Japanese 日本語 | About International Rectifier | Contact Us | Privacy ?1995- 2010 International Rectifier https://ec.irf.com/v6/en/US/adirect/ir?cmd=catProductDetailFrame&productID=IRPLLED7[2012-6-14 6:23:31] Application Note AN-1171 IRPLLED7 90-250VAC Offline LED Driver using IRS2980 By Peter B. Green Table of Contents Page 1. Introduction ......................................................................................2 2. Constant Current Control .................................................................3 3. High Voltage Regulator ....................................................................5 4. Current Sense Level Shifter .............................................................5 5. PWM Dimming .................................................................................6 6. IRPLLED7 Circuit Schematic ...........................................................7 7. Bill of Materials.................................................................................8 8. PCB Layout ......................................................................................9 9. Test Results .....................................................................................10 10. Component Temperatures .............................................................12 11. Design Procedure Summary ..........................................................10 Safety Warning! The IRPLLED7 LED driver does not provide safety isolation. When operating the output drive to the LEDs can produce potentially dangerous voltages. This board is intended for evaluation purposes only and should be handled by qualified electrical engineers only! www.irf.com AN-1171 1 EVALUATION BOARD - IRPLLED7 1. Introduction Solid state light sources are now available that offer viable alternatives to Fluorescent and HID lamps and far surpass incandescent lamps. Luminous efficacy expressed in Lumens per Watt has now reached levels enabling LEDs to be used for general illumination. High brightness LEDs also possess the added advantages of longer operating life span up to 50000 hours and greater robustness than other less efficient light sources making them suitable for outside applications such as street lighting. High power LEDs are ideally driven with constant regulated DC current, requiring a "driver" or "converter" to provide the required current from an AC or DC power source. A simple single stage power converter based around the IRS2980 LED driver IC provides a controlled current output over a wide AC line or DC voltage input range. The IRPLLED7 evaluation board is an off line non-isolated constant current Buck regulator LED driver designed to supply a 350mA DC output current. The LED output voltage can be up to 90% of the input voltage, operating from an AC line input voltage between 90 and 250VAC 50/60Hz. It also includes PWM dimming capability from 10% to 100% of light output controlled by an on board potentiometer. Important Safety Information The IRPLLED7 does not provide galvanic isolation of the LED drive output from the line input. Therefore if the system is supplied directly from a non-isolated input, an electrical shock hazard exists at the LED outputs and these should not be touched during operation. Although the output voltage is low this electrical shock hazard still exists. It is recommended that for laboratory evaluation that the IRPLLED7 board be used with an isolated AC or DC input supply. The IRS2980 series Buck topology www.irf.com AN-1171 2 is suitable only for final applications where isolation is either not necessary or provided elsewhere in the system. Figure 1: IRPLLED7 Block Diagram 2. Constant current control The IRS2980 is a hysteretic Buck controller operating in continuous conduction mode (CCM) and using a low side switching MOSFET as the controlled switch and a fast recovery diode as the uncontrolled switch connected to the positive DC bus. This mode of operation is opposite to the IRS25401 and includes a differential floating high side current sense circuit, which is used to hysteretically control the output current by sensing the voltage drop across a sense resistor and regulating the average to 0.5V. The IRS2980 is designed for use in current regulated circuits and not voltage regulated circuits. Figure 2: IRS2980 Basic Schematic www.irf.com AN-1171 3 Figure 2 illustrates how the current is sensed by differentially measuring the voltage between the HV and CS inputs, RF and CF have been added to provide noise filtering. When the MOSFET (MBUCK) is switched on the current in the inductor LBUCK rises linearly according to the relationship: Vin − Vout = Lbuck . di dt Where Vin is the bus voltage rectified from the AC line voltage and Vout is the combined series voltage of the string of LEDs making up the load. When the voltage at HV rises to 0.55V with respect to CS the gate drive to MBUCK switches off. When the MBUCK is off the inductor current flows instead through DBUCK. During this period the current decreases linearly according to the relationship: Vout = − Lbuck . di dt When the voltage at HV falls to 0.45V with respect to CS the gate drive to MBUCK switches on. The cycle repeats continuously to provide an average current in LBUCK which supplies the LED load. The frequency and duty cycle are dependent on the input and output voltages and the value of the LBUCK as can be inferred from the equations. The output current can be set by selecting the appropriate value of RCS according to the relationship: Iout (avg ) = VCS RCS where VCS is 0.5V, therefore for an RCS of 1.5V, the output current will be nominally 333mA. In practice there are some additional propagation delays in the circuit which give rise to some error in the current regulation and some variation over input voltage, however the performance is more than adequate for LED applications as shown in the test results section. Accuracy of regulation and amplitude of the current ripple are tradeoffs against inductor size. The IRS2980 incorporates a frequency limiting function that prevents the frequency from exceeding approximately 150kHz. This is necessary in order to limit the VCC current consumption since the internal high voltage regulator can supply only a limited current (ICC) which is dominated by gate drive current. Gate current charges and discharges the MOSFET gate capacitance during each switching cycle and therefore increases with frequency. www.irf.com AN-1171 4 3. High Voltage Regulator The IRS2980 contains an internal high voltage regulator to supply VCC from the high voltage DC bus. Figure 2 shows that pin 1 (HV) is connected directly the DC bus. Current is supplied to the VCC supply at pin 2 through an internal current source capable of operating up to 450V. The internal regulator can supply up to 3mA, which is sufficient to supply VCC for most MOSFET gate capacitances and frequencies normally required in an LED driver. ICC can be reduced by selecting a MOSFET with a low gate capacitance (25nC or less) and selecting an inductance (LBUCK) that will allow the regulator to operate at a reduced frequency. A regulator operating at 60kHz for example will require much less ICC than one operating at 120kHz. As explained earlier this is a tradeoff against inductor size. It is also important to consider the temperature rise of the IRS2980. Since the internal regulator operates linearly the associated power loss is dependent on bus voltage and ICC. More care must be taken at higher bus voltages to minimize frequency and ICC to minimize the IC operating temperature. The addition of heat sinking in the form of large areas of copper on the PCB or thermally conductive potting compounds can significantly reduce temperature. Inductor values are generally larger for 220V off line AC applications than for 120V in order to reduce switching frequency, which lowers power dissipation in the circuit. 4. Current sense level shifter The IRS2980 uses a floating differential current sense circuit to measure the LED current in the high side of the supply circuit. The Buck regulator configuration uses a low side switch, which is opposite to the IRS25401. In order to realize average current control the current must be sensed both when the MOSFET (MBUCK) is switched on and when it is switched off and therefore must be sensed at the high side. In order to accomplish this the hysteretic current sensing circuitry within the IRS2980 is situated within a floating high side well constructed by means of International Rectifiers HVIC technology. A floating supply voltage (nominally 8V) for the circuitry contained within this well is developed between the HV and VS pins of the IC. The supply is provided by a current source located between VS and COM. The high side contains a comparator with defined hysteresis connected to a -0.5V reference with respect to HV. The output from the comparator is transferred through high voltage level shift circuitry to the gate driver circuitry, which is referenced to COM. The incorporation of the floating high side well allows the LED current to be sensed at voltages up to 450V above COM. www.irf.com AN-1171 5 5. PWM Dimming The IRS2980 includes a PWM dimming oscillator that provides a linear ramp waveform at the RAMP pin with the frequency determined by an external capacitor to COM (CRAMP). The IRPLLED7 demo board uses a passive valley fill circuit comprising two electrolytic capacitors, three diodes and one resistor to provide a high power factor (>0.9) without the additional cost of an additional active stage. This circuit (C2,C5,D2,D3,D4 and R3) can be seen in the schematic shown in section 6. The passive valley fill circuit however, creates a high ripple on the DC bus at twice the line frequency (50-60Hz). The constant current Buck regulator is easily capable of compensating for this, however in PWM dimming designs it means that the PWM frequency needs to be significantly higher than 120Hz in order to avoid visible flicker of the LEDs. The PWM dimming frequency in the IRPLLED7 demo board is approximately 800Hz determined by a CRAMP value of 10nF. The dimming ramp varies between 0 and 2V and is compared with a DC dimming control voltage from 0 to 2V applied to the ADIM input at pin 5. The IRPLLED7 board includes a pot which adjusts the ADIM input over the 0 to 2V range to provide the full range of dimming. Figure 3: IRPLLED7 PWM Dimming Figure 3 shows the output current to the LED load at a dimming level of about 30%. It can be seen that the amount of current ripple varies slightly due to the DC bus voltage created by the passive valley fill circuit. At this PWM frequency there is no noticeable flicker during dimming. The IRS2980 is designed for PWM not linear dimming. For linear dimming applications the IRS25401 may be used, which can operate in either or both modes. An IRS2980 based circuit could be produced that would be dimmable from a triac based dimmer, however this would require the addition of external phase detection and bleed circuitry (please refer to IRS2981 for this application). www.irf.com AN-1171 6 6. IRPLLED7 Circuit Schematic Figure 4: IRPLLED7 Complete Schematic www.irf.com AN-1171 7 7. Bill of Materials Item Description Part Number Manufacurer Quantity Reference 1 IC, LED Controller IRS2980S International Rectifier 1 IC1 2 Rectifier ,1A , 400V, SMA S1G-13-F Diodes Inc 3 D2,D3,D4 3 Diode, 1A, 600V, 35nS, SMB MURHS160T3G On Semiconduct or 1 D1 DF10S Fairchild 1 BR1 IRFR812 International Rectifier 1 M1 B32652A3104J Epcos 1 C1 1206A102JAT2A AVX 1 C4 GRM319R71H10 4KA01D Murata 2 C6, C9 EEU-EB2E220 Panasonic 2 C2, C5 Vishay 1 C3 AVX 1 C8 Murata 1 C7 ERJ-1TYJ1R5U Panasonic 1 R2 PR01000101009 JR500 Vishay 2 R1, R3 ERJ-8GEYJ153V Panasonic 1 R4 ERJ-8GEYJ100V Panasonic 1 R5 ERJ-8GEYJ102V Panasonic 1 R6 3386P-1-502LF Bourns Inc 1 R7 B82477G4105M Epcos 2 L1, L2 5009 Keystone 2 5005 Keystone 1 5006 Keystone 1 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Bridge, 1000V, 1.5A, 4SDIP MOSFET, 500V, 2.2Ohm, DPAK Capacitor, 100nF, 250VAC, Radial Capacitor, 1nF, 50V, 5%, 1206 Capacitor, 0.1uF, 50V, 10%, 1206 Capacitor, 22uF, 250VDC, 20% Capacitor, 0.22uF, 500VDC, 2225 Capacitor, 22nF, 50V, 1206 Capacitor, 0.01uF, 50V, 10%, 1206 Resistor, 1.5Ohm, 1W, 5%, 2512 Resistor, 10Ohm, 1W, 5%, Axial Resistor, 15K, 0.25W, 5%, 1206 Resistor, 10, 0.25W, 5%, 1206 Resistor, 1K, 0.25W, 5%, 1206 Pot, 5K, 0.5W, Single, Top adjust Inductor, 1mH, 0.55A, 1.68Ohm Test point, 0.063"D Yellow Test point, 0.063"D Red Test point, 0.063"D Black PCB www.irf.com VJ2225Y224KXE AT 12065C223KAT2 A GRM319R71H10 3KA01D IRPLLED7 Rev C AN-1171 1 8 8. PCB Layout Top Overlay Top Copper Bottom Overlay Bottom Copper Layout Considerations It is very important when laying out the PCB for the IRS2980 based LED driver to consider the following points: 1. CVCC (C6) and CHVS (C8) must be as close to IC1 as possible. 2. The feedback path should be kept to a minimum length and separated as much as possible from high frequency switching traces to minimize noise at the CS input. 3. The current sense filter components RF (R6) and CF (C4) should be located close to the IRS2980 with short direct traces. 4. It is essential that all signal and power grounds should be kept separated from each other to prevent noise from entering the control environment. www.irf.com AN-1171 9 Signal and power grounds should be connected together at one point only, which must be at the COM pin of the IRS2980. The IRS2980 may not operate in a stable manner if these guidelines are not followed! All low side components associated with the IC should be connected to the IC signal ground (COM) with the shortest path possible. 5. All traces carrying the load current need to be sized accordingly. 6. Gate drive traces should also be kept to a minimum length. 9. Test Results Measurements were carried out using a variable DC power supply and a load of 7 white LEDs being driven at a nominal 350mA. DC Input Voltage (V) 60 70 80 90 100 110 120 130 140 150 160 170 180 DC Input Current (A) 0.14 0.12 0.11 0.10 0.09 0.08 0.07 0.07 0.07 0.06 0.06 0.06 0.05 Output Voltage (V) 20.1 20.1 20.1 20.1 20.1 20.1 20.1 20.1 20.1 20.1 20.1 20.1 20.1 Output Current (mAav) 335 340 344 349 353 357 360 364 367 370 373 375 377 Ripple (mApp) Frequency Duty (kHz) Cycle (%) 120 140 150 160 180 190 190 200 200 210 220 230 240 98 99 99 97 95 94 92 89 87 85 83 81 80 40 36 30 26 23 21 19 17.6 16.2 15.2 14.2 13.4 12.6 Table 1: IRPLLED7 Test Results As expected table 1 indicates that the duty cycle is approximately equal to Vout/Vin, the LED total voltage drop divided by the supply voltage. It can be seen that the current ripple increases as the duty cycle reduces since the voltage difference is increasing. This is because: Vin − Vout = Lbuck . di dt and therefore di/dt is increasing, which results in more overshoot in the hysteretic comparator due to inevitable propagation delays in the system. These delays actually provide an advantage because the operating frequency is decreasing with higher input voltage which limits ICC and switching losses in both MBUCK (M1) and DBUCK (D1). www.irf.com AN-1171 10 The gate drive and output current waveforms are displayed in Figure 5: Input = 60VDC Efficiency = 80.2% Input = 180VDC Efficiency = 75.3% Green Trace = Gate Drive Blue Trace = Output Current Figure 5: IRPLLED7 Test Waveforms In the example shown in table 1, the efficiency is calculated at 80.2% for 60VDC input and 20V output at a current of 335mA. When the input for the same load is increased to 180VDC the efficiency falls to 75.3% and the output current increases to an average of 377mA. These efficiency results are reasonable for 9W LED load. If the board is connected to a 120VAC line input the efficiency would be close to 80% due to the reduced bus voltage provided by the passive valley fill circuit over much of the AC cycle. The IRPLLED7 board uses an inductor of 1mA. Increasing this value would reduce frequency and ripple. Ripple can also be reduced by adding a capacitor to the output although this is not necessary in most applications and may reduce the PWM dimming range. In the example shown in figure 6 below, where a load of fewer series LEDs was attached an efficiency of 86% was calculated: www.irf.com AN-1171 11 Yellow = Gate, Green = LED Current Vin = 60V, Iin = 0.09A, Pin = 5.4W Vout = 13.87, Iout = 0.338A, Pout = 4.66W Efficiency = 86.0% Figure 6: IRPLLED7 Efficiency Meaasurement 10. Component Temperatures In the following example, an combination of LEDs was connected with a combined voltage drop of approximately 30V. The board is capable of operating down to 60VDC input, below which the high voltage regulator does not operate. In applications requiring a lower input voltage VCC can be supplied directly from an alternate source, the simplest option being a resistor from the DC bus to VCC. DC Bus Voltage (V) 60 70 80 90 100 110 120 130 140 150 160 170 180 Output Voltage (V) 30.76 30.60 30.55 30.52 30.43 30.43 30.43 30.43 30.44 30.45 30.47 30.49 30.51 Output Current (mAav) 334 330 329 329 331 332 335 337 340 343 346 349 353 Ripple (mApp) Frequency (kHz) Duty Cycle (%) 100 110 120 130 140 150 150 160 170 170 170 170 170 150 154 155 155 157 157 158 159 159 160 160 161 161 54.4 46 41.8 37.3 33.0 30.3 27.4 25.2 25 23.1 21.6 20.5 19.6 Table 2: IRPLLED7 Additional Test Results www.irf.com AN-1171 12 In this case the body temperature in free air at ambient 25ºC was measured using a thermocouple giving a result of 73ºC at 180V input. For a 120VAC supply the temperature rise would be expected to be smaller since the bus voltage is lower for most of the line cycle. Since the IRS2980 incorporates an internal high voltage regulator and level shifting circuitry it dissipates some heat during operation which increases with frequency and line voltage. It is necessary as with the MOSFET (MBUCK) and diode (DBUCK) to ensure that these components do not overheat in the application. This is done by providing additional copper around the components on the PCB to allow heat conduction from the devices. In 220VAC off line applications is is necessary to use a suffliciently large inductor (LBUCK) in order to maintain a low operating frequency in the 30 to 60kHz range. This will substantially reduce heat dissipation in all of the components mentioned. The 1mH inductor used in the IRPLLED7 demo board may not be adequate in a 220VAC input design without sufficient heat sinking. A value of 3.3mH is typically used for a 350mA LED output current at 220VAC. 11. Design Procedure Summary 1. Determine the systems requirements: input/output voltage and current needed 2. Calculate current sense resistor 3. Determine the operating frequency required. 4. Select LBUCK so that they maintain supply into the load during t_HO_on. 5. Select the switching MOSFET and diode) to minimize gate drive current and switching losses. IR WORLD HEADQUARTERS: 101 N. Sepulveda Blvd., El Segundo, California 90245 Tel: (310) 252-7105 Data and specifications subject to change without notice. 9/8/2011 www.irf.com AN-1171 13