标签: UPS

01 物联网系统中为什么要使用USB 接口芯片 在物联网系统中使用USB接口芯片的原因主要基于USB接口的多种优势及其与物联网设备的兼容性。以下是详细分析： 1、广泛的兼容性与标准化 USB接口已成为消费性和工业电子产品的标准接口之一，具有广泛的兼容性。物联网设备通过集成USB接口芯片，可以方便地与其他具有USB接口的设备进行连接和数据交换，无需担心兼容性问题。 2、高效的数据传输能力 USB接口支持多种数据传输速率，从USB 1.1的12 Mbps到USB 3.x的数千Mbps不等。这种高效的数据传输能力使得物联网设备能够快速地与计算机、服务器或其他设备进行数据通信，满足物联网系统对实时性和高效性的要求。 3、灵活的电力供应 USB接口不仅用于数据传输，还可以为连接的设备提供电力。在物联网系统中，许多设备需要持续供电以保持正常运行。通过USB接口供电，可以简化电源设计，减少设备体积和重量，提高设备的便携性和灵活性。 4、易于扩展和升级 USB接口支持热插拔功能，即在不关闭系统电源的情况下，可以连接或断开USB设备。这使得物联网系统在扩展或升级时更加灵活方便。例如，可以通过USB接口连接新的传感器、执行器等设备，或更新设备的固件和驱动程序。 5、丰富的外设支持 USB接口支持多种外设，包括键盘、鼠标、打印机、摄像头、存储设备等。在物联网系统中，这些外设可以用于数据采集、人机交互、数据存储等多种场景。通过集成USB接口芯片，物联网设备可以轻松地与这些外设进行连接和使用。 6、低功耗设计 尽管USB接口在小型、便携式设备上可能会增加电流消耗，但现代USB接口芯片和技术已经提供了低功耗解决方案。例如，USB Type-C接口提供了更高的电力传输效率，同时支持多种电源管理功能，有助于降低设备的功耗和延长电池寿命。 7、强大的软件支持 USB接口得到了广泛的软件支持，包括操作系统层面的驱动程序和应用程序层面的API接口。这使得物联网设备可以轻松地与各种软件和应用程序进行集成和交互，实现更复杂的功能和应用场景。 8、应用场景 USB接口芯片的应用场景非常广泛，几乎涵盖了所有需要数据传输和连接外部设备的领域。主要包括： 计算机和外围设备连接：如打印机、扫描仪、摄像头、音频设备等。 嵌入式系统：如智能手机、平板电脑、数字相机等。 汽车电子：用于车载娱乐系统、导航系统、安全系统等的数据传输和通信。 医疗设备：用于医疗设备与计算机或其他设备之间的数据传输和监控。 工业控制：在工业自动化和机器人控制中，USB接口芯片用于实现设备之间的数据交互和控制。 综上所述，物联网系统中使用USB接口芯片的原因主要包括广泛的兼容性与标准化、高效的数据传输能力、灵活的电力供应、易于扩展和升级、丰富的外设支持、低功耗设计以及强大的软件支持等。这些优势使得USB接口芯片成为物联网系统中不可或缺的组成部分。 本文会再为大家详解电接口芯片家族中的一员——USB接口芯片。 02 USB接口芯片定义 USB接口芯片是指按照USB总线协议进行通信，并通过内部集成的逻辑电路将USB通信内容转化为其他接口（如SPI、I2C）或电位信号，以控制其他装置（如鼠标、键盘、音箱、GPS等）的芯片。USB（Universal Serial Bus，通用串行总线）是一种串口总线标准，也是一种输入输出接口的技术规范，被广泛地应用于个人电脑和移动设备等信息通讯产品，并扩展至摄影器材、数字电视（机顶盒）、游戏机等其它相关领域。 03 USB接口芯片的原理 USB接口芯片的核心是USB控制器，它包含了USB通信协议的处理逻辑和数据缓存功能。当USB设备插入计算机或其他主机设备时，USB接口芯片会检测到设备的插入，并向主机发送插入信号。主机在接收到插入信号后，会发送设备识别请求，芯片会根据请求返回设备的信息。之后，主机和设备之间会进行一系列的数据传输和通信，芯片会负责处理和管理这些数据。当设备被拔出时，芯片会向主机发送拔出信号，主机会断开与设备的连接。 TTL电平、COMS电平、232电平、USB电平信号的主要特性 04 USB接口芯片的分类 USB接口芯片主要分为三大类： USB主控制器芯片：主要负责实现主机与USB设备之间的数据传输。 USB集线器芯片：可以将一个USB接口的信号和电力传输到另外几个USB接口。 USB功能设备芯片：主要负责USB接口的连接和中断处理，以及各种USB设备的识别、协议转换和控制等功能。 05 USB接口芯片的选型参数 在选择USB接口芯片时，需要考虑以下参数： 兼容性：确保芯片支持所需的USB版本（如USB 2.0、USB 3.0、USB 3.1等）和设备类型。 数据传输速度：根据应用需求选择合适的数据传输速度。 功耗：考虑芯片的功耗是否符合设备的电源要求。 封装形式：根据PCB布局和空间限制选择合适的封装形式。 内置功能：如是否需要内置时钟、EEPROM等。 06 不同设备之间USB通信方案选择 PC机上的通信接口有USB接口，相应电平逻辑遵照USB原则；还有DB9接口（九针口），相应电平逻辑遵照RS-232原则。 而我们的单片机上的串行通信通过单片机的RXD、TXD、VCC、GND四个引脚，相应电平逻辑遵照TTL原则。 当然，新手小白买的学习板上肯定都已经集成了类似PL2303、CP2102之类的USB转TTL芯片，相应接口也变成了USB接口；有些学习板上集成的是MAX232之类的TTL转RS-232芯片，相应的接口也变成了DB9接口。 转换的目的是把电平转换到双方都能识别，下面分类举例： 情况1：PC机USB口与不带电平转换芯片的单片机通信 方法：外购USB转TTL模块，如下图所示。该模块一端接入PC机的USB接口，另一端有TXD、RXD、GND、5V、3.3V五个引脚，分别与单片机的RXD、TXD、GND、5V引脚相连，对于采用3.3V供电的单片机则把5V改为3.3V即可。该模块核心就是一块PL2303、CP2102芯片进行USB与TTL电平的转换。 情况2：PC机USB口与集成了USB转TTL芯片的单片机通信 方法：直接用USB线连接即可，只是单片机上的USB接口形式有时会不同，根据A-USB、B-USB、micro-USB、mini-USB分别选择合适的接线 情况3：PC机USB口与集成了TTL转RS-232芯片的单片机通信 方法：外购USB转RS-232模块，如下图所示。该模块核心是在DB9的一端有一块CH340或CH341电平转换芯片，把RS-232电平转换为USB电平 情况4：PC机DB9接口与不带电平转换芯片的单片机通信 方法：外购RS232转TTL模块，如下图所示。该模块一端是DB9与PC机DB9连接，一端是RXD、TXD、VCC、GND与单片机相应引脚连接。其核心是一块max232电平转换芯片。 情况5：PC机DB9接口与成了USB转TTL芯片的单片机通信 方法：一般不会这么进行通信PC机上DB9接口都有了还会没有USB接口？如果非要进行，外购RS-232转USB模块，如上面提到过的 情况6：PC机DB9接口与成了RS-232转TTL芯片的单片机通信 方法：直接用DB9（串口线）连接即可！ 用一张图总结一下以上几种情况： 最后，别忘了PC端还要安装相应的驱动程序哦！ 07 USB接口芯片的使用注意事项 供电电压：确保为USB接口芯片提供正确的供电电压，通常为5V或3.3V。 信号完整性：在PCB设计中注意USB信号线的布局和走线，避免信号干扰和衰减。 驱动安装：确保在使用前已安装正确的驱动程序，以避免设备无法识别或功能异常。 热插拔：虽然USB接口支持热插拔，但在插拔过程中应避免暴力操作，以免损坏接口或芯片。 静电防护：在连接或断开USB设备时，注意静电防护，避免静电对芯片造成损害。 08 USB接口芯片的厂商 USB接口芯片的厂商众多，包括但不限于英特尔（Intel）、德州仪器（TI）、微芯科技（Microchip）、恩智浦（NXP）、威盛电子（VIA）等。此外，还有一些专注于USB接口芯片研发的国内厂商，如南京沁恒微电子股份有限公司等。这些厂商提供了多种类型、不同规格和性能的USB接口芯片供用户选择。 供应商A:沁恒微电子 1、产品能力 （1）选型手册 （2）主推型号1:CH340N 对应的产品详情介绍 沁恒微电子的CH340N是一款USB转串口芯片，它在多个领域都有广泛的应用。以下是对CH340N的详细介绍： 一、基本信息 品牌：WCH/沁恒 型号：CH340N 封装形式：SOP-8，这种封装形式使得芯片尺寸小，便于在PCB上布局。 内部特性：内置晶振，无需外部晶振电路，简化了外围电路设计。 二、电气参数 电源电压：根据参考文章，CH340N支持3.3V和5V电源电压。但请注意，不同来源的信息可能有所差异。例如，有信息指出其最小电源电压为3V，最大电源电压为8V（可能是指在不同应用或测试条件下的极限值），但在实际应用中，常见的供电电压为3.3V或5V。 工作温度：支持较宽的工作温度范围，最小工作温度为-50°C，最大工作温度可达100°C或更高（具体取决于不同来源的信息）。 三、应用特点 外围电路简单：CH340N的应用电路相对简单，没有冗余的复杂设计，使得用户使用起来更加便捷。 成本低：作为国产芯片，CH340N的成本相对较低，符合当前的经济贸易趋势。 易于集成：由于其小巧的封装形式和内置晶振的特性，CH340N易于集成到各种电子设备中。 广泛应用：CH340N可广泛应用于便携式低功耗产品、消费类电子产品、智能电表、商业机器人激光雷达等领域，实现USB与串口之间的转换。 四、使用注意事项 供电电压：确保为CH340N提供正确的供电电压，避免电压过高或过低导致芯片损坏。 信号完整性：在PCB设计中注意USB信号线的布局和走线，避免信号干扰和衰减。 驱动安装：在使用前，确保已在上位机（如PC）上安装了CH340N的驱动程序，以便正确识别和使用设备。 静电防护：在连接或断开USB设备时，注意静电防护，避免静电对芯片造成损害。 五、应用场景 便携式低功耗产品：如智能手表、蓝牙耳机等，CH340N可用于实现USB充电和调试功能。 消费类电子产品：如打印机、扫描仪等，CH340N可用于将设备的串口信息通过USB传输到上位机进行显示或处理。 智能电表：在智能电表中，CH340N可用于实现USB接口与电表内部电路之间的通信，以便将用电信息传输到云端服务器。 商业机器人激光雷达：在商用机器人雷达中，CH340N可用于提供稳定、高速的数据传输解决方案。 六、厂商信息 南京沁恒微电子股份有限公司是一家专注于连接技术和微处理器内核研究的集成电路设计企业。该公司基于自研专业接口IP、微处理器内核IP构建芯片，致力于为客户提供万物互联、上下互通的芯片及解决方案。其主要产品包括USB/蓝牙/以太网接口芯片和连接型/互联型/无线型MCU等。 综上所述，沁恒微电子的CH340N是一款功能强大、易于使用且成本较低的USB转串口芯片，在多个领域都有广泛的应用前景。 硬件参考设计 研发设计注意使用事项 上图是统一供电方式下MCU单片机通过TTL串口连接CH340芯片实现USB通讯的参考电路。该产品选择自供电方式，VCC支持5V或者3.3V（VCC为3.3V时V3需短接到VCC），完全不使用USB总线电源VBUS（如有需要MCU可以通过I/O串电阻后检测其是否有效）。CH340与MCU使用同一电源VCC，所以CH340与MCU之间不存在双电源通过I/O相互电流倒灌的情形。CH340没有使用到的信号线都可以悬空。对于CH340C/N/K/E/X/B芯片，无需X6和C17及C18 核心料（哪些项目在用） NB定位器traker,eSIM读卡表控制板项目 （1）技术产品 技术资料 CH340DS1.PDF （如有侵权，联系删除） 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UPS （不间断电源）是当今各行业中不可或缺的电力设备，它的作用在于确保设备在电力异常或停电时仍能持续稳定运行。 UPS 的基本工作原理是将电力储存在内置的电池中，在正常情况下，它将稳定的电力供应给设备；当检测到电力异常或断电时， UPS 会立即切换到备用电源模式，以确保设备继续运行，直至恢复到正常电力供应状态。它被广泛运用于医疗、通信、工业控制等领域，不仅提供稳定的电力支持，也保障设备在电网波动或断电情况下的安全运行。 UPS 电源通常由整流器、锂电池、逆变器和静态开关等多个组件构成。锂电池作为 UPS 储能电源的核心，能够为设备提供稳定可靠的电力输出。 Amass LC 系列电源连接器在连接核心部件与其他组件之间扮演着关键的角色。 它具备多项出色的优点： 1. 小巧便携：适应了现代户外移动电源的设计趋势，接头体积小巧轻便，方便在狭小空间内进行电源插头安装。 Amass 电源连接器尺寸仅为硬币大小，方便携带和使用。 2. 防尘防水：采用 PBT 材质，具备耐摔、抗震和防水等特性，适应各种恶劣天气和多尘环境，确保设备在极端环境下的安全运行。 3. 一体化设计：有助于实现设备整体紧凑设计，使得 UPS 内部的锂电池和线路连接更为紧凑。这样的设计不仅使外观更为整洁，还能减少外部因素对便携式 UPS 设备的影响。 Amass LC 系列电源连接器，作为连接 UPS 系统的关键组件之一，确保了设备在各类环境下的稳定运行，为系统提供了可靠的电力支持。 欲了解更多有关 UPS 电源连接器的详细信息，欢迎访问艾迈斯官网。

【导读】随着世界变得更加先进，我们对电力的依赖变得更加严重。若没有电，最高端的房屋也可能变得相当原始。本文描述家用不间断电源的设计，其作用是让家中最重要的服务—Wi-Fi—保持畅通。 问题: 停电期间如何使用Wi-Fi和其他家用设备？ 答案: 可以使用汽车电池作为备用电源，设计家用不间断电源(UPS)。该电源连接至降压-升压 转换器 ，生成稳定的12 V/5 A电源，用于为Wi-Fi路由器供电；连接至6.5 V/1.5 A降压转换器，为无绳电话供电。 简介 随着世界变得更加先进，我们对电力的依赖变得更加严重。若没有电，最高端的房屋也可能变得相当原始。本文描述家用不间断电源的设计，其作用是让家中最重要的服务—Wi-Fi—保持畅通。 家用不间断电源(UPS) 图1中的电路是出于需要而设计的。2022年初的能源危机迫在眉睫，世界和平正在刀尖上跳舞，这个电路就是为了在断电的情况下保持家中Wi-Fi畅通。Wi-Fi路由器重启平均需要2分多钟，这可能被认为是"第一世界"的问题，但如果在电话会议的中途断电，这个等待时间会让人觉得非常漫长。即使是轻微的压降也可能引起重大问题。该家用不间断电源设计为Wi-Fi接入点（和任何其他电子设备）提供12 V/5 A电源，并为无绳电话提供额外的6.5 V/1.5 A电源。这足以使大多数笔记本电脑与外界进行通信。 图 1. 不间断电源 (UPS) 原理图 图1显示的便是该电路。此设计的备用电源是从废品站以20英镑购买的二手汽车电池。 LTC3789 是一个四开关降压-升压转换器，能以极高效率提供恒定的12 V电源，其输入电压可以高于或低于此电压。其评估套件在5 V到36 V输入电压条件下能提供12 V、5 A的电源输出，因此可以直接使用，无需修改。Wi-Fi路由器仅需要1 A电流，因此该评估套件可用于为其他许多需要12 V电压的应用供电。 无绳电话需要6.5 V、约600 mA电源，因此选择 LT8608 来为此电源轨提供低噪声、高效率电源，其静态电流极低(2.5μA)。LT8608和LTC3789的最大输入电压分别为42 V和38 V，因此将它们直接连接到汽车电池以实现最高电路效率。某些较低成本的 电池充电器 如果未正确连接到电池，可能会产生高电压，导致电池无法充分吸收充电电流。因此，如果充电器与电路连接良好，但与电池连接不良，那么产生的电压可能会损坏电子设备。LTC3789和LT8608的宽输入电压范围减轻了连接电池充电器时产生高电压的担忧。电路既可以在永久连接电池充电器的情况下工作，也可以在没有连接的情况下工作。但是，在不通风的室内保持电池充电器永久连接的安全方面取决于所用的电池和充电器的类型。 该电路的精巧部分由 LTC4416提供。这是一个双通道理想二极管，负责切换主电源电压和备用电源。LTC4416含有一个精密比较器，当比较器检测到主电源发生故障时，就会使用四个外部P沟道 MOSFET (PFET)切换到备用电源。 该电路的更简单形式是双通道二极管OR配置，两个二极管的阴极连接在一起，主电源和备用电源连接到阳极。然而，该电路仅将两个电源中的最高者馈送到位于阴极的输出端，并会在二极管上产生0.6 V的损耗。用PFET代替二极管可以设计更高效的电路。测量PFET体二极管两端的电压降，如果它超过某个阈值，则FET导通，从而使体二极管短路。如果此电压降为负，则对PFET的驱动被移除，体二极管会阻止反向电流。这样就创建了一个具有低正向电压降和反向阻断功能的理想二极管，如图2所示。 图 2. 二极管 OR 电路的理想二极管实现 在该电路中，每个PFET的体二极管从输入指向输出，因此如果一个输入电压比另一个输入电压高出600 mV以上，该体二极管就会导通。因此，如果备用电源恰好高于主电源，负载的电源将由备用电源提供，这是不可取的。反转PFET可以解决这个问题，但如果输出电压比输入电压高出600 mV以上，体二极管就会导通，发生电流倒流。 更简洁的解决方案是为每条路径添加一个额外的PFET，如图3所示。在该电路中，两个体二极管彼此相对，因此当FET断开时，该电路提供双向开路，并隔离每个通道，而不管输入或输出电压如何。 图 3. 具有双向断开功能的二极管 OR 电路 对于12 V电路，LTC4416 ( DC 1059A)的评估套件做了修改，以提供11.17 V的切换电压，其中R3使用100 kΩ 电阻 ，R1使用10 kΩ + 2.2 kΩ电阻。这很有效，但我们发现，Wi-Fi接入点需要精确的12 V电源，有时候当12 V主电源再次切换回来时，它会重新启动。这是由于电压阶跃（从11.17 V到12 V）扰乱了路由器电子器件。将R1改为11.47 kΩ可将切换电压提高到11.8 V，从而减小了电压阶跃的大小。 无绳电话电路对电源阶跃的感受更强烈，因此R15由22 kΩ + 10 kΩ电阻组成，以提供5 V的切换电压。 波形如图4所示。绿色迹线显示的是LTC4416始终开启的12 V输出，红色迹线显示的插墙式 电源适配器 的12 V输出（主电源），蓝色迹线显示的是汽车电池电压。当 示波器 直流耦合时，看不到对绿色迹线的干扰。找元器件现货上唯样商城。更改为交流耦合后，当连接(600 ms)和断开(5.8 s)主电源12V时，可以看到很小的干扰。具有讽刺意味的是，当连接12 V主电源时，该电源轨上的噪声明显更高，这表明插墙式电源 适配器 输出的噪声高于LTC3789。 图 4. 当主电源（红色迹线）断开时，12 V（绿色迹线）几乎不受干扰 图5所示为UPS电子设备的照片，完整电路如图6所示。 图 5. 电源和理想二极管安装在 UPS 箱的侧面 图 6. 带电池的完整电路 未来改进 前面提到的电路需要切断来自插墙式电源适配器的电缆，以允许串联插入UPS。一个更简洁的解决方案是从汽车电池产生340 V DC，并将其馈入扩展插座，然后将插墙式电源适配器插入扩展插座。由于所有插墙式电源适配器的内部电路都包含整流器，因此该电压是交流还是直流没有关系。然而，从12 V电池产生340 V电压会带来损耗，在插墙式电源适配器内降低该电压也会产生损耗，这意味着低压电路将更 加高 效和简单，哪怕需要切断插墙式电源 适配器电缆 。 LTC4416评估套件含有LED，可指示正在使用主电源还是备用电源，而且很容易将这些LED放到外壳上。另一个有用的附加功能是一个按钮开关，用于人为将LTC4416的使能引脚拉低以测试切换功能。 该电路经过广泛测试，性能优异。对于更高的电流，可以使用N沟道理想二极管。LTC4416是ADI公司提供的各种理想二极管和热插拔器件的一种。 结论 本文描述的电路展示了一种简单家用不间断电源的设计，它可以在断电时让各种家用电器保持运行。此电路当然可以进行修改，使用更强大的MOSFET和更大的电池来提供更高的输出功率和更长的后援时间。

Whether we like it or not, business is complicated and full of compromises, but some compromises make the whole system fail.   As engineers, we often focus our efforts on the details of a product design. Some engineers specialize in blank-slate design. Others focus on test and quality engineering. Still others provide expert guidance for manufacturing processes. It seems that, no matter what the industry, "almost acceptable" products have become the norm for what we collectively have come to believe is "good."   I'm not saying that every component of every product isn't good. But to me, "product" means my entire experience, from researching for products to selecting candidate solutions to purchasing the chosen product to receiving it. For me, a failure in any part of this supply chain engagement results in, at best, an almost acceptable product.   I've recently encountered a series of almost acceptable products -- not because the items themselves were poorly designed or manufactured, but because other aspects of the product experience were unacceptable.   A year ago, a company with which I was consulting received a sample of a PCIe chassis, backplane, and enclosure. The fit and finish were excellent -- the sheet metal was bright plated, and the seams were welded. This was a great solution for a new design challenge to repackage a research machine into a commercially acceptable enclosure. Based on experience, I thought this enclosure would give us a fighting chance to pass electromagnetic emissions standards for the new machine. We ordered a chassis and enclosure based on the sample unit we'd evaluated. What we received was vastly different from the evaluation unit.   I recently had dinner with executives from the company, and I asked about the change. They were surprised by the difference in what we'd evaluated and what we received. It seems that we had evaluated a Mil-Spec chassis and enclosure, but our understanding was that it was the commercial unit. We subsequently discovered that the salesperson had ordered a commercial evaluation unit, but evidently a Mil-Spec counterpart had been shipped by mistake. The jury is out on this almost adequate product. The executives inform me that the commercial unit with the same essential electronics that we use passes FCC part B. We'll see.   How about another almost adequate product? I recently received a single-board computer with a dual Xeon processor and 48 GB of DDR3 RAM. It's a powerful board that can handle the data it will be required to process. It's pretty nice for a dual-slot board. The only problem is that it isn't really a dual-slot card. Yes, the card itself occupies two slots of the PCIe backplane, but the cabling from the peripherals in the front of the enclosure requires another two slots. Also, perhaps the missed failure in this case is the fact that the custom heat sink requires cooling fans to be placed on top of the heat sink. The supplier's answer? "Customers put a short board next to this card for airflow."   Here's yet another almost adequate item from a colleague of mine. A medical device design requires a medical grade isolated UPS. After significant research and paper evaluation, a UPS was selected. It weighs more than 70 pounds. He ordered a single unit of this multi-thousand-dollar UPS and waited patiently for it to arrive. The big day came, and a truck arrived with the unit. It was heavy -- more than 100 pounds. The packaging material was pretty destroyed during the shipping process. Damage to the UPS itself wasn't visible until the box had been removed. Inside a second box was a collection of UPS pieces that had been part of the original unit. The UPS had come loose from its mini shipping pallet and evidently had traveled from Texas to California bouncing all of its 70+ pounds on the now-destroyed faceplate.   Of course, shipping accidents do happen. Another unit was shipped to replace the first unit. This arrived in a box that had been secured with duct tape. It too had broken loose from its pallet and had a destroyed front panel.   It was not exactly amusing that both of these units had wood attached to the faceplate with wood screws. Even if the shipping hadn't damaged the UPS, the wood screws holding a piece of wood onto the faceplate would have been enough to return the damaged unit.   Try entry number three -- another distributor, another order, another delivery. This time, the box came off in the hands of the delivery person. Once again, wood screws went through the wood and into the faceplate. Finally, my colleague called the manufacturer. The company agreed to ship a unit direct, even though its corporate policy was to send small orders through a distributor. This fourth unit looks like it has arrived intact, with no wood screws holding wood on to the faceplate.   These anecdotes illustrate three ways that products can become almost adequate: a change in production methods, a grossly inadequate datasheet, and shipping failures. We haven't considered the almost adequate design decisions that are all around us: the Christmas lights that might last a few dozen hours before they fail, "long-life" compact fluorescent light bulbs that fail as fast as their incandescent cousins, supermarket bagels that are moldy when the bag is opened only a few hours after they are bought. The list goes on and on.   There are some truly good products, but all too often we accept mediocrity. It's time to do away with "almost adequate" and make "good" mean what it says. There's no room for wiggling out by redefining words.   Henry Davis is an independent contractor.

For several years now, my girlfriend and I have been growing restless. We live in Colorado in the US, you see, and yearn for a life in the mountains. Clear air, chilly weather, spectacular views, massive drifts of snow. It's in our very blood and bones. So we decided to do something drastic: We sold most of our household possessions, purchased a travel trailer and some mountain land, and set off for our new lives. If only it were quite that simple.   Garage sale! (All photos: Benjamin Goldstone) You may now be asking yourself how this has anything at all to do with a "product that I tore into to fix or improve it." I ask only for your patience, as this is a story about fixing our lives as much as a product. Or perhaps "hacking" would be a more apt term, as we decided to explore the limits of a travel trailer as well as ourselves. Our plan? To brave the elements at 9,600 feet in one of the most beautiful places in the world to pursue that dream... in a three-season RV. Yep, we must be nuts. As our budget was only $5,000 for our new home, we needed to get creative. A fully winterized, fully furnished RV runs far above the $5,000 mark, so we purchased the best used unit we could find. The previous owners hadn't maintained it to quite the degree they should have, and so a number of repairs were in order. First and foremost was the fridge. It was not properly cooling. In fact, even on the warmest setting, instead of cooling things it would freeze everything in it. Uh oh. The issue could be one of a number of things. Most likely either the thermistor or the control circuit board was bad. I grabbed my multi-meter, set it to detect resistance, and placed the thermistor in ice. It registered 8kΩ, within the 7-10kΩ range it should be in. When placed in warm water, the multi-meter averaged 2kΩ. The thermistor was not the issue. Upon pulling the cover off of the control board, it was immediately apparent that one of the capacitors was having issues as it was bulging. After soldering in a new capacitor, the fridge began to cycle and cool food properly. But wait, now suddenly the light in the fridge was only intermittently working. After ensuring the connections to the power sources (both AC and DC) were solid and that the components on both the control and settings boards were all working as required, I pulled the light itself apart. Two of the contacts within the switch were no longer solidly connecting when the switch closed—one of those cases where a fix to one thing reveals another unrelated issue. I stripped the plastic off of a twist tie for a garbage bag, cut the wire within to size, and wrapped both sides of the switch so when closed, the switch would function reliably. Now the fridge is in perfectly functional order. A number of other minor repairs in the RV were also immediately required. The vent on the roof above the fridge, used to keep the fins on the fridge cool, had been mostly broken off, allowing in the elements. Nothing to do but remove the remnants of the old vent and install a new one. Additionally, the grip tape on the stairs needed to be replaced; the interior was ugly as sin and needed painting; a number of latches were broken; the windows in the door had fallen down into the door; etc, etc. "Oy Vey!" As my grandmother would have said. But this is the life we signed up for. A couple of trips to the RV supply shop and days later everything is back in working order. Now, while we work on clearing our land of dead trees, we have found a gig at a local state park that provides space for our RV and trucks in return for a minor amount of work. As it happens that space is on the top ridge of a mountain, situated at 9,600 feet (convert to m), just below the timberline. Taking an RV designed for three season use and turning it into a living space capable of weathering winters with average snow falls of 80+ inches and temperatures down to -30 degrees F is no small feat. Most RVs are not designed for that kind of living, and ours certainly wasn't. While not really a design fault, we do need something that will keep us and our pets warm through the harsh winter ahead. As it's quite likely that we will be snowed in at least once this winter, redundancy and proper preparation are of paramount importance. We started by making a list. So far, we have resealed the trailer with silicone caulk and expanding foam sealant, insulated underneath, applied heat-tape to the exposed drain pipes, applied heat shrink to the windows, and purchased the supplies to skirt the trailer. We have also purchased bear spray, backup heaters, a generator, a solar panel and charge controller, backup propane, emergency first aid kits, as well as backup food and water supplies—and, of course, a whole mess of snow gear to supplement what we already have. Never one to simply leave things be, however, I have started working on additional projects. A backup UPS for the heat tape and other critical AC systems is a must. A DC-to-AC inverter for running AC systems while boondocking is also necessary. I'm most looking forward to my new Raspberry-Pi/Arduino-based control system idea for controlling and monitoring the entire trailer. While a lot of work, this new lifestyle has certainly delivered our dreams, and I wouldn't trade it for the world. I do, however, now know how the characters in the epic A Song of Ice and Fire felt when they said "Winter is coming." For us, lady winter is truly on her way, and she is going to be brutal. Wish us luck. Ben Goldstone lives in Colorado, US and owsn a small IT consulting business. He has been into everything tech related since he disassembled his parents' lawn mower at the age of eight... and couldn't put it back together properly after the timing gear fell out. His love for tech is matched only by his thirst for knowledge, pursuit for audio nirvana, and love for the outdoors. He submitted this article as part of Frankenstein's Fix, a design contest hosted by EE Times (US).