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ROHM芯片BD9211F的应用文档一、芯片各引脚基本功能：本芯片包含18个引脚，各个引脚功能及说明如下：图一IC内部结构图1、VCC：芯片供电。
电压范围：8V-18V；Vcc max=20V。
VCC引脚对地电容必须大于0.1uF，用于滤除噪声干扰。
2、STB：此引脚用于设置ON/OFF信号，当芯片关断时需要将其进行复位。
STB信号电压幅度需小于VCC电压幅度，若STB电压提前于VCC电压供给芯片，需要保证STB电压幅度小于4V。
原因如下图二所示：当VCC未建立，且STB电压建立时，若电压太大，会导致STB 与VCC间二极管导通，此时STB 电压会串到VCC电压上，导致芯片误动作。
图二STB引脚内部结构图STB引脚电压在0.8V和2V之间的状态为不定态，此电压有可能会使芯片误动作，因此要避免STB电压在这个区域间的状态。
3、GND：小信号地，尽可能的与PGND分开走。
这样可以保证在短的GND和PGND回路上有更少的干扰信号，GND信号尽量靠近连接插座。
4、RT：设定IC内部的充放电电流从而决定工作频率；改变RT引脚与地之间电阻的阻值，可以通过下图三公式设置基本驱动频率：图三基本驱动频率理论计算公式如：（①RT对地电阻33KΩ,基本频率为：178KHz；②RT对地电阻47KΩ,基本频率为：126KHz；③RT对地电阻51KΩ,基本频率为：116KHz；④RT对地电阻56KΩ,基本频率为：106KHz；）基本频率意思为N1、N2输出的频率仅由RT与GND之间的电阻决定。
频率会因为RT与FB之间的电阻Radj而改变。
下图四、图五中可以看出，改变FB与RT之间电阻RADJ的阻值可以调整频率范围。
当RADJ=100KΩ,∆Fout=84.46kHz.图四电阻Radj的取值与频率范围关系（Radj=100KΩ）图五FB电压范围与频率范围关系（Radj=100KΩ）RT与GND之间的电阻RRT决定基本频率。
基本频率是当FB=1.5V，在这个条件下运算频率调制范围且由RADJ决定。
Zener DiodeEDZ6.8B●Applications●Dimensions (Unit : mm)●Land size figure (Unit : mm)Constant voltage control●Features1)2-pin ultra mini-mold type for high-density mounting (EMD2)2) High reliability3)Can be mounted automatically,using chip mounter.●Construction●Silicon epitaxial planer●Electical voltage (Ta=25︒C)(２)The operating resistances(Zz,Zzk) are measured by superimposing a minute alternating curren on the regulated current(Iz)y0.0010.010.11105101520253035400.111010010000.0010.010.11101001000P O W E R D I S S I P A T I O N :P d (W )TIME : t(ms)PRSM-TIME CHARACTERISTICST E M P .C O E F F I C I E N C E :γz (％/℃)ZENER VOLTAGE : Vz(V)γz-Vz CHARACTERISTICS TIME : t(s)Rth-t CHARACTERISTICST R A N S I E N T T H A E R M A L I M P E D A N C E :R t h (℃/W )R E V E RS E S U R G E M A X I M U M P O W E R :P R S M (W )2040608010012014016002550751001251500.11101001000100000.0010.010.1110100Z E N E R C U R R E N T :I z (m A )ZENER VOLTAGE:Vz(V)Vz-Iz CHARACTERISTICS-0.08-0.06-0.04-0.0200.020.040.060.080.10.12010203040-50510152025303540AMBIENT TEMPERATURE : Ta(℃)Pd-Ta CHARACTERISTICS T E M P .C O E F F I C I E N C E :γz (m V /℃)LEDZ6.8BL a st Ti me Bu yNoticePrecaution on using ROHM Products1. Our Products are designed and manufactured for application in ordinary electronic equipments (such as AV equipment,OA equipment, telecommunication equipment, home electronic appliances, amusement equipment, etc.). If youintend to use our Products in devices requiring extremely high reliability (such as medical equipment(Note 1), transport equipment, traffic equipment, aircraft/spacecraft, nuclear power controllers, fuel controllers, car equipment including car accessories, safety devices, etc.) and whose malfunction or failure may cause loss of human life, bodily injury or serious damage to property (“Specific Applications”), please consult with the ROHM sales representative in advance. Unless otherwise agreed in writing by ROHM in advance, ROHM shall not be in any way responsible or liable for any damages, expenses or losses incurred by you or third parties arising from the use of any ROHM’s Products for Specific Applications.(Note1) Medical Equipment Classification of the Specific ApplicationsJAPAN USA EU CHINA CLASS Ⅲ CLASS Ⅲ CLASS ⅡbCLASS ⅢCLASS Ⅳ CLASS Ⅲ2. ROHM designs and manufactures its Products subject to strict quality control system. However, semiconductorproducts can fail or malfunction at a certain rate. Please be sure to implement, at your own responsibilities, adequate safety measures including but not limited to fail-safe design against the physical injury, damage to any property, which a failure or malfunction of our Products may cause. The following are examples of safety measures:[a] Installation of protection circuits or other protective devices to improve system safety [b] Installation of redundant circuits to reduce the impact of single or multiple circuit failure3. Our Products are designed and manufactured for use under standard conditions and not under any special orextraordinary environments or conditions, as exemplified below. Accordingly, ROHM shall not be in any way responsible or liable for any damages, expenses or losses arising from the use of any ROHM’s Products under any special or extraordinary environments or conditions. If you intend to use our Products under any special or extraordinary environments or conditions (as exemplified below), your independent verification and confirmation of product performance, reliability, etc, prior to use, must be necessary:[a] Use of our Products in any types of liquid, including water, oils, chemicals, and organic solvents [b] Use of our Products outdoors or in places where the Products are exposed to direct sunlight or dust[c] Use of our Products in places where the Products are exposed to sea wind or corrosive gases, including Cl 2, H 2S, NH 3, SO 2, and NO 2[d] Use of our Products in places where the Products are exposed to static electricity or electromagnetic waves [e] Use of our Products in proximity to heat-producing components, plastic cords, or other flammable items [f] Sealing or coating our Products with resin or other coating materials[g] Use of our Products without cleaning residue of flux (even if you use no-clean type fluxes, cleaning residue of flux is recommended); or Washing our Products by using water or water-soluble cleaning agents for cleaning residue after soldering[h] Use of the Products in places subject to dew condensation4. The Products are not subject to radiation-proof design.5. Please verify and confirm characteristics of the final or mounted products in using the Products.6. In particular, if a transient load (a large amount of load applied in a short period of time, such as pulse. is applied,confirmation of performance characteristics after on-board mounting is strongly recommended. Avoid applying power exceeding normal rated power; exceeding the power rating under steady-state loading condition may negatively affect product performance and reliability.7. De-rate Power Dissipation (Pd) depending on Ambient temperature (Ta). When used in sealed area, confirm the actualambient temperature.8. Confirm that operation temperature is within the specified range described in the product specification.9. ROHM shall not be in any way responsible or liable for failure induced under deviant condition from what is defined inthis document.Precaution for Mounting / Circuit board design1. When a highly active halogenous (chlorine, bromine, etc.) flux is used, the residue of flux may negatively affect productperformance and reliability.2. In principle, the reflow soldering method must be used on a surface-mount products, the flow soldering method mustbe used on a through hole mount products. If the flow soldering method is preferred on a surface-mount products, please consult with the ROHM representative in advance. For details, please refer to ROHM Mounting specificationL a st Ti me Bu yPrecautions Regarding Application Examples and External Circuits1. If change is made to the constant of an external circuit, please allow a sufficient margin considering variations of thecharacteristics of the Products and external components, including transient characteristics, as well as static characteristics.2. You agree that application notes, reference designs, and associated data and information contained in this documentare presented only as guidance for Products use. 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Product performance and soldered connections may deteriorate if the Products are stored in the places where:[a] the Products are exposed to sea winds or corrosive gases, including Cl2, H2S, NH3, SO2, and NO2 [b] the temperature or humidity exceeds those recommended by ROHM [c] the Products are exposed to direct sunshine or condensation [d] the Products are exposed to high Electrostatic2. Even under ROHM recommended storage condition, solderability of products out of recommended storage time periodmay be degraded. It is strongly recommended to confirm solderability before using Products of which storage time is exceeding the recommended storage time period.3. Store / transport cartons in the correct direction, which is indicated on a carton with a symbol. Otherwise bent leadsmay occur due to excessive stress applied when dropping of a carton.4. Use Products within the specified time after opening a humidity barrier bag. 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Before purchasing or using ROHM’s Products, please confirm the la test information with a ROHM sale s representative.3. The information contained in this doc ument is provi ded on an “as is” basis and ROHM does not warrant that allinformation contained in this document is accurate an d/or error-free. ROHM shall not be in an y way responsible or liable for any damages, expenses or losses incurred by you or third parties resulting from inaccuracy or errors of or concerning such information.L a st Ti me Bu y。
User’s GuideROHM Solution Simulator3.5V to 40V Input, 1A Single 2.2MHz Buck DC/DC Converter for AutomotiveBD9P105MUF-C / Load ResponseThis circuit simulate the load response of BD9P105MUF-C. You can observe the fluctuation of the output voltage when the load current is abruptly changed. You can customize the parameters of the components shown in blue, such as VIN, IOUT, or peripheral components, and simulate the load response with desired operating condition.General CautionsCaution 1: The values from the simulation results are not guaranteed. Please use these results as a guide for your design. Caution 2: These model characteristics are specifically at Ta=25°C. Thus, the simulation result with temperature variancesmay significantly differ from the result with the one done at actual application board (actual measurement).Caution 3: Please refer to the datasheet for details of the technical information.Caution 4: The characteristics may change depending on the actual board design and ROHM strongly recommend to doublecheck those characteristics with actual board where the chips will be mounted on.1. Simulation SchematicFigure 1. Simulation Schematic2. How to simulateThe simulation settings, such as simulation time or convergence options, are configurable from the ‘Simulation Settings’ shown in Figure 2, and Table 1 shows the default setup of the simulation.In case of simulation convergence issue, you can change advanced options to solve.The default statement “.tran 0 2.4m 0.4m” in ‘Manual Options’ sets the simulation execution options. By default, run for t=2.4ms and save the waveforms after t=0.4ms. You can modify or delete it.Refer to Section 3 about the sentence “.param V_VBAT=12”.Figure 2. Simulation Settings and executionSimulation Settings Simulate3. Simulation Conditions3.1 How to define VIN voltage (VBAT and VEN setting)The VBAT and VEN voltages are set in the ‘Manual Options’ text box for parameter setting consistency. The voltage level of VBAT and VEN, and the initial voltage of CBLK refer to the variable V_VBAT. To define the voltage level, set the V_VBAT value in ‘.param’ sentence in the text box from ‘Simulation Settings’ > ‘Advanced Options’ as shown in Figure 3.‘Simulation Settings’Figure 3. Definition of VIN voltage.In order to secure the simulation stability those three parameters should be the same. So do not change those parameters respectively.3.2 IOUT parameter setupFigure 4 shows how the IOUT parameters correspond to the IOUT stimulus waveform.(b) Magnified viewFigure 4. IOUT parameters and its waveforms IOUT VOUT IOUT VOUT VIN4. BD9P105MUF-C_Tran modelTable 3 and Table 4 shows the model terminal function implemented. Note that BD9P105MUF-C_Tran is the behavior model for its load/line response operation, and no protection circuits or the functions not related to the purpose are not implemented.(Note 3) This model is not compatible with the external synchronization function.(Note 4) Use the simulation results only as a design guide and the data reported herein is not a guaranteed value.4.1 Parameter TSSBD9P105MUF-C_Tran model has the property ‘TSS’, which is the soft start time describ ed in page 7 of the datasheet.The product has 3ms (typical) of the startup time of the output voltage. You can short cut the soft start by changing TSS value. The default TSS value is set to 0.2ms in this simulation and you can modify the value in the property editor.Figure 5. TSS property of BD9P105MUF-C_Tran5. Peripheral Components5.1 Bill of MaterialTable 5 shows the list of components used in the simulation schematic. Each of the capacitor and inductor has the parameters of equivalent circuit shown below. The default value of equivalent components are set to zero except for the parallel resistance of L1. You can modify the values of each component.5.2 Capacitor Equivalent Circuits(a) Property editor (b) Equivalent circuitFigure 6. Capacitor property editor and equivalent circuit5.3 Inductor Equivalent Circuits(a) Property editor (b) Equivalent circuitFigure 7. Inductor property editor and equivalent circuitThe default value of PAR_RES is 6.6kohm.(Note 5) These parameters can take any positive value or zero in simulation but it does not guarantee the operation of the IC in any condition. Refer to the datasheet to determine adequate value of parameters.6 Link to the product information and tools6.1 Product webpage link: https:///products/power-management/switching-regulators/integrated-fet/buck-converters-synchronous/bd9p105muf-c-product6.2 Related documentsThe application notes are available from ‘Documentation’ tab of the product page.6.3 Design assist tools ar e available from ‘Tools’ tab of the product page.The Circuit constant calculation sheet is useful for deciding the application circuit constants.NoticeROHM Customer Support Systemhttps:///contact/Thank you for your accessing to ROHM product informations.More detail product informations and catalogs are available, please contact us.N o t e sThe information contained herein is subject to change without notice.Before you use our Products, please contact our sales representative and verify the latest specifica-tions :Although ROHM is continuously working to improve product reliability and quality, semicon-ductors can break down and malfunction due to various factors.Therefore, in order to prevent personal injury or fire arising from failure, please take safety measures such as complying with the derating characteristics, implementing redundant and fire prevention designs, and utilizing backups and fail-safe procedures. ROHM shall have no responsibility for any damages arising out of the use of our Poducts beyond the rating specified by ROHM.Examples of application circuits, circuit constants and any other information contained herein areprovided only to illustrate the standard usage and operations of the Products. The peripheral conditions must be taken into account when designing circuits for mass production.The technical information specified herein is intended only to show the typical functions of andexamples of application circuits for the Products. ROHM does not grant you, explicitly or implicitly, any license to use or exercise intellectual property or other rights held by ROHM or any other parties. ROHM shall have no responsibility whatsoever for any dispute arising out of the use of such technical information.The Products specified in this document are not designed to be radiation tolerant.For use of our Products in applications requiring a high degree of reliability (as exemplifiedbelow), please contact and consult with a ROHM representative : transportation equipment (i.e. cars, ships, trains), primary communication equipment, traffic lights, fire/crime prevention, safety equipment, medical systems, servers, solar cells, and power transmission systems.Do not use our Products in applications requiring extremely high reliability, such as aerospaceequipment, nuclear power control systems, and submarine repeaters.ROHM shall have no responsibility for any damages or injury arising from non-compliance withthe recommended usage conditions and specifications contained herein.ROHM has used reasonable care to ensur e the accuracy of the information contained in thisdocument. However, ROHM does not warrants that such information is error-free, and ROHM shall have no responsibility for any damages arising from any inaccuracy or misprint of such information.Please use the Products in accordance with any applicable environmental laws and regulations,such as the RoHS Directive. For more details, including RoHS compatibility, please contact a ROHM sales office. ROHM shall have no responsibility for any damages or losses resulting non-compliance with any applicable laws or regulations.W hen providing our Products and technologies contained in this document to other countries,you must abide by the procedures and provisions stipulated in all applicable export laws and regulations, including without limitation the US Export Administration Regulations and the Foreign Exchange and Foreign Trade Act.This document, in part or in whole, may not be reprinted or reproduced without prior consent ofROHM.1) 2)3)4)5)6)7)8)9)10)11)12)13)。
ROHM开发出80V级高耐压DC/DC转换器“BD9G341AEFJ”【ROHM半导体（上海）有限公司10月27日上海讯】全球知名半导体制造商ROHM面向需要大功率（高电压×大电流）的通信基站和工业设备领域，开发出耐压高达80V的MOSFET 内置型DC/DC转换器“BD9G341AEFJ”。
“BD9G341AEFJ”采用功率系统工艺0.6µm的高耐压BiCDMOS，作为非绝缘型DC/DC 转换器，实现了80V的业界最高耐压水平，在ROHM的DC/DC转换器产品阵容中，也是耐压最高的产品。
利用ROHM擅长的模拟设计技术优势，在80V级的DC/DC转换器中，还实现了业界最高的转换效率。
与一般产品相比，本产品即使输出引脚发生意外短路（接触），也可通过保护电路抑制发热从而防止产品受损，因此还非常有助于提高应用产品的可靠性。
不仅如此，这些优势仅通过简单的小型8引脚封装即完全实现，可减少安装面积和周边零部件数量。
本产品于2015年10月开始以月产6万个的规模投入量产（样品价格 600日元/个：不含税）。
前期工序的生产基地为ROHM滨松株式会社（滨松市），后期工序的生产基地为ROHM Electronics Philippines, Inc.（菲律宾）。
今后，ROHM将充分发挥所擅长的模拟设计技术优势，继续开发高耐压、高效率、高可靠性的电源IC。
＜背景＞近年来，节能意识几乎在所有的领域持续高涨。
即使是在大功率工业设备类产品中，可支持大功率的功率元器件和电源IC节能型半导体的应用越来越广泛。
而当用于大功率产品时，为确保受到因雷电等导致的突发性浪涌电压时产品也不损坏，要求产品的耐压水平高于输入电压。
ROHM利用所擅长的最尖端的功率系统工艺和垂直统合型一条龙生产线，不仅可确保产品的特性，而且还面向非常重视可连续工作的可靠性和长期稳定供应的工业设备市场，开发出众多新产品。
此次，ROHM面向因智能手机的流量增加而需求日益扩大的通信基站和高性能化发展迅速的工厂FA设备、电机应用领域，开发出业界最高级别耐压的80V级DC/DC转换器。
物料长代码物料名称品牌总量2SAR552PGZET100Transistor/晶体管Rohm/罗姆417000 FMY6T148Transistor/晶体管Rohm/罗姆150000 UMH10NTN Transistor/晶体管Rohm/罗姆537000 UMD3NGTR Transistor/晶体管Rohm/罗姆354000 DTC023JEBTL Transistor/晶体管Rohm/罗姆798000 2SA1727 TLQ Transistor/晶体管Rohm/罗姆40000 2SCR523EBTL Transistor/晶体管Rohm/罗姆330000 2SA1774 TLR Transistor/晶体管Rohm/罗姆225000 EMD22T2R Transistor/晶体管Rohm/罗姆96000 LTC143ZMFS8T2L Transistor/晶体管Rohm/罗姆152000 2SK3065 T100Transistor/晶体管Rohm/罗姆16000 2SC5824T100R Transistor/晶体管Rohm/罗姆17000 RJU002N06 T106Transistor/晶体管Rohm/罗姆66000 2SD2537T100V Transistor/晶体管Rohm/罗姆10000 DTC044EEBTL Transistor/晶体管Rohm/罗姆99000 UMZ1N TR Transistor/晶体管Rohm/罗姆36000 DTC014YEBTL Transistor/晶体管Rohm/罗姆75000 EMD6T2R Transistor/晶体管Rohm/罗姆24000 DTC143ZMT2L Transistor/晶体管Rohm/罗姆48000 2SA2030T2L Transistor/晶体管Rohm/罗姆16000 2SD1782K T146R Transistor/晶体管Rohm/罗姆15000 RTR025N03TL Transistor/晶体管Rohm/罗姆9000 EMD3T2R Transistor/晶体管Rohm/罗姆16000 EMF5T2R Transistor/晶体管Rohm/罗姆8000 DTC115EUAT106Transistor/晶体管Rohm/罗姆15000 2SB1236ATV2P Transistor/晶体管Rohm/罗姆2500 MMSTA06T146Transistor/晶体管Rohm/罗姆9000 DTC043ZMT2L Transistor/晶体管Rohm/罗姆24000 RTR025P02TL Transistor/晶体管Rohm/罗姆3000 DTC114TETL Transistor/晶体管Rohm/罗姆18000。
Application Note热设计关于绝缘垫片的热阻的注意点对于TO (Transistor Outlines)封装等，在背面有用于散热的裸漏金属焊盘（散热焊盘）的封装形式，当将这种非绝缘型的封装安装在散热片上时，会经由封装的金属焊盘对散热片施加高压，因此需要使用绝缘垫片进行隔离。
在进行热估算时，如果绝缘垫片的热阻取值不恰当，会无法得到正确的热估算结果，因此本应用手册记载了关于绝缘垫片的热阻的注意点。
图1是TO封装之一的TO-247封装的外观图。
在背面有用于散热的裸漏金属焊盘，如果是MOSFET产品，该焊盘和封装内部的芯片（半导体芯片）的漏极存在电气连接，因此在电路应用中会存在高压。
当将此封装安装在散热片上时，如图2所示，需要在封装和散热片之间插入绝缘型的散热垫片。
在散热片和TO封装之间，通常会使用螺丝或者夹片等固定件进行加压使两者牢固接触。
加压时的压力会造成绝缘垫片产生压缩并使其热阻发生变化。
热阻发生变化的原因，包括压力所导致的接触热阻变化等。
获取绝缘垫片的热阻在查看绝缘垫片的产品目录和官网的公开规格时，会发现不同厂家的描述不一样，有的厂家的产品规格里包含了接触热阻、有的没有包含接触热阻，也有的将压力作为参数进行了记载等。
即便是对于包含了接触热阻的规格值，也需要考虑接触热阻随垫片两端的接触材质和表面粗糙度所产生的变化。
有的产品在规格里只记载了导热系数。
导热系数是物质固有的参数，用来表示物质内部发生热转移的难易程度，与产品的厚度无关，同时因为无法判断接触热阻，有可能造成热估算偏小。
因此，需要从垫片厂商获取与实际使用的压力值所匹配的热阻数据来进行热估算。
图3是低硬度的绝缘垫片、图4是高硬度的绝缘垫片的示例。
低硬度的绝缘垫片会在施加压力时变薄，因此垫片自身的热阻会变低。
高硬度的绝缘垫片在施加压力时厚度几乎不变，但是热阻也会变低，这是因为当施加压力时，接触热阻会变低。
对于高硬度的绝缘垫片，接触热阻会在垫片两端的接触材质和表面粗糙度变化时可能变大，因此更容易受到压力的影响。
ROHM芯片BD9211F的应用文档一、芯片各引脚基本功能：本芯片包含18个引脚，各个引脚功能及说明如下：图一IC内部结构图1、VCC：芯片供电。
电压范围：8V-18V；Vcc max=20V。
VCC引脚对地电容必须大于0.1uF，用于滤除噪声干扰。
2、STB：此引脚用于设置ON/OFF信号，当芯片关断时需要将其进行复位。
STB信号电压幅度需小于VCC电压幅度，若STB电压提前于VCC电压供给芯片，需要保证STB电压幅度小于4V。
原因如下图二所示：当VCC未建立，且STB电压建立时，若电压太大，会导致STB 与VCC间二极管导通，此时STB 电压会串到VCC电压上，导致芯片误动作。
图二STB引脚内部结构图STB引脚电压在0.8V和2V之间的状态为不定态，此电压有可能会使芯片误动作，因此要避免STB电压在这个区域间的状态。
3、GND：小信号地，尽可能的与PGND分开走。
这样可以保证在短的GND和PGND回路上有更少的干扰信号，GND信号尽量靠近连接插座。
4、RT：设定IC内部的充放电电流从而决定工作频率；改变RT引脚与地之间电阻的阻值，可以通过下图三公式设置基本驱动频率：图三基本驱动频率理论计算公式如：（①RT对地电阻33KΩ,基本频率为：178KHz；②RT对地电阻47KΩ,基本频率为：126KHz；③RT对地电阻51KΩ,基本频率为：116KHz；④RT对地电阻56KΩ,基本频率为：106KHz；）基本频率意思为N1、N2输出的频率仅由RT与GND之间的电阻决定。
频率会因为RT与FB之间的电阻Radj而改变。
下图四、图五中可以看出，改变FB与RT之间电阻RADJ的阻值可以调整频率范围。
当RADJ=100KΩ,∆Fout=84.46kHz.图四电阻Radj的取值与频率范围关系（Radj=100KΩ）图五FB电压范围与频率范围关系（Radj=100KΩ）RT与GND之间的电阻RRT决定基本频率。
基本频率是当FB=1.5V，在这个条件下运算频率调制范围且由RADJ决定。
