一个月黑风高的夜晚。
表情与外面的风暴相匹配，一个坚固的十字军在他的五点式安全带上弯曲，并且在等待光线改变的同时，不耐烦地用戴着手套的手轻拍在他的定制电动车的车轮上。
他迟到了与当地警察局的特殊训练课。
如果他没有小睡，他就不会迟到。
骑士的朋友，哲学家，红颜知己和个人应用工程师阿尔弗雷德已经决定在本周早些时候被拖入72小时不间断的犯罪斗争之后不要叫醒他。
蝙蝠EV配备了雷达逃避和防撞措施 - 向他自己设计的飞行哺乳动物致敬 - 但在与戈登酋长的军官合作的这一天，黑暗骑士承诺自己不会采取自由行动
与城市的法律。
他毕竟发誓要服务和保护。
在灯变绿之前的几分之一秒，他用电动机开了枪，感觉车辆向前冲了830匹马。
肾上腺素激增从未使磨损的神经和肌肉酸痛恢复活力。
突然间，他感到车辆右侧受到了一阵颤抖。
Two-Face将一个钻形轮毂的尖端撞向了蝙蝠EV的前部，使凯夫拉尔覆盖的钢制挡泥板凹陷，并打破了前一天阿尔弗雷德如此精心打磨的前照灯罩。
在这个过程中，一个LED从其焊点中被扭曲并变得无法操作，而另一个LED直接受到撞击。
它闪烁了一秒钟，然后作为短路继续失败。
幸运的是，蝙蝠-EV的灯配备了安森美半导体的LED分流器，它在8微秒内绕过了丢失的LED，并保持了串中其他LED的电流连续性。
短路的LED停止发光，但继续传输电流。
对于现在来说，一切看起来都很好。
然而潜伏在短路LED中的是一种灾难性故障的机制，因为功率继续消散并导致焊点和共晶凸点上的热应力。
无论是制造定制的打击犯罪的车辆还是较便宜的儿童移动设备，部件故障都会导致巨大的成本。
在某些情况下，成本只不过是对最终用户的简单不便。
在其他情况下，它可能意味着召回，法律责任和安全隐患。
尽管LED具有固有的可靠性，但设计人员可能希望采用其他措施来提高可靠性。
一种方法是使用安森美半导体LED分流器。
与飞翼复仇者的汽车一样，失效的LED可能表现为开路或短路。
如果要对LED的状态进行电子监控，则会产生棘手的挑战。
监控电路必须应对多个故障特征。
作为简单而不是复杂解决方案的粉丝，Alfred自然决定使用LED分流器来解决这个问题，实质上是将开路转换为短路。
如果一个LED有一个分流器，它无论是短路还是开路，它的电压降都会很低。
对于监控电路，功能LED将具有高逻辑电平，而故障LED将具有低逻辑电平。
如下表所示，使用分流器时，只有两个可能的LED电压电平。
在额外的逻辑电路的帮助下，这种二进制高或低信号被Alfred用于广泛的目的。
例如，一个新的设计说明演示了如果主LED在小于50微秒的转换中失效，使用LED分流器自动切换到辅助LED，LED灯的寿命如何能够有效地加倍。
在这次冲击之后，蒙面的猎人对自己微笑着，欣赏讽刺的是，即使在他试图遵守规则的时候，他也会被侧滑。
来自安森美半导体的传感器在他的座位上表示体温下降，因为他冷静地想到了他的选择。
接近传感器在他的座位上移动时通过单向通道向阿尔弗雷德发送数据，并且在追求双面时将操纵杆转向右侧。
右侧轮胎上的安森美半导体压力传感器表明，由冲击引起的泄漏已经自密封回到正常水平......但我们离题了。
更直接的关注是，当他挥动方向盘并努力打开转向信号时，撞击造成的损坏使其无法操作。
可靠性和安全性在车辆中至关重要。
如果转向信号灯发生故障，信号传输能力将大大降低。
由于这种安全隐患，转向信号灯需要在故障后立即更换。
为了缓解这个问题，安森美半导体创造了智能大灯电路。
在一些前照灯模块中，转向信号LED旁边有一个日间行车灯LED灯串。
由于一种新颖的方案，如果后者失败，这个日间行车灯串将闪烁而不是转向灯。
通过将HBL5006 LED分流器与LED和监控电路配合使用，可以实现这一切。
HBL5006用于此前照灯以及监控电路，以便在转向信号LED发生故障时使日间行车灯闪烁。
安森美半导体的LED分流器产品组合正在不断扩展，以满足几乎所有LED照明应用的需求。
NUD4700采用专有技术，可在高电流下实现极其高效的操作。
用于HBL5006的超紧凑型SOD-923封装尺寸仅为0.65 mm2，额定工作电流为350 mA。
LED分流器易于添加，可提高任何LED模块的可靠性，从而使我们最着名的客户在Gotham的街道上保持安全。
在这个场合，随着蝙蝠-EV转向追逐对手，两面的涡轮增压赛车加速到远处。
蝙蝠-EV很容易跟随并赶上，但是卡丁车决定在最后一次凌空射击并转回交通，在他预约的途中。
即使面对嘲弄的敌人，也必须保持承诺。
回到家里，阿尔伯特松了一口气，默默地感谢安森美半导体的LED旁路分流器。
NUD4700的运行温度为1.3 A，外壳温度仅为73.3°C。
该设备安装在测试PCB上，红外摄像机的十字准线位于设备顶部。
以上来自于谷歌翻译
以下为原文
It was a dark and stormy night. With an expression that matched the storm outside, a caped crusader flexed against his five point harness and tapped a gloved hand impatiently on the wheel of his customized electric vehicle while waiting for the light to change. He was late for a special combat training session with the local police department. If only he hadn’t taken a nap, he wouldn’t have been late. Alfred, the knight’s friend, philosopher, confidante, and personal applications engineer, had decided not to wake him after the non-stop 72 hour spree of crime-fighting he had been dragged into earlier in the week.
The bat-EV was equipped with radar-evasion and collision-avoidance measures – a tribute to the flying mammal he had styled himself after - but on this day of cooperating with Chief Gordon’s officers the dark knight had promised himself he wouldn’t take liberties with the laws of the city. He had vowed to serve and protect after all. A fraction of a second before the light turned green, he gunned the motor and felt the vehicle surge forward with the power of 830 horses. The adrenaline rush never failed to rejuvenate frayed nerves, and aching muscles.
Suddenly, he felt a shuddering impact on his vehicle’s right side. Two-Face had rammed the pointy end of a drill-shaped wheel hub into the front of the bat-EV, denting the Kevlar-covered steel fender and cracking the headlamp cover that Alfred had so lovingly polished just the other day. In the process one LED was wrenched out of its solder joint and rendered inoperable, while another suffered a direct hit. It flickered for a second and proceeded to fail as a short circuit. Fortunately the bat-EV’s lamps were equipped with LED shunts from ON Semiconductor, which bypassed the missing LED within eight microseconds and maintained current-continuity for the other LEDs in the string. The shorted LED stopped emitting light but continued to carry current.
All was seemingly well with the headlamp… for now. However lurking in the shorted LED was a mechanism for catastrophic failure as power continued to dissipate and cause thermal stress on solder joints and eutectic bumps.
Whether one is building a customized crime-fighting vehicle or a less expensive kids-mobile, component failure can lead to enormous costs. In some cases, the cost is nothing more than a simple inconvenience to the end user. In other cases it can mean recalls, legal liabilities, and safety hazards. Although LEDs are inherently reliable, designers may wish to implement additional measures to increase reliability. One way to do this is by using ON Semiconductor LED shunts.
As in the winged-avenger’s car, a failed LED may appear as an open or a short circuit. If the state of the LED is to be electronically monitored, this creates a tricky challenge. The monitoring circuitry must contend with multiple failure signatures.
As a fan of simplicity over complicated solutions, Alfred had naturally decided on the use of LED shunts to solve this problem, essentially converting an open circuit into a short circuit. If an LED has a shunt across it and it fails either as a short or an open, its voltage drop will be low. To monitoring circuitry, a functional LED will have a high logic level and a failed LED will have a low logic level. As the table below illustrates, there are only two possible LED voltage levels when the shunt is used.
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With the help of additional logic circuitry, this binary high or low signal was exploited by Alfred for a wide range of purposes. For example, a new design note demonstrates how the lifetime of an LED lamp can effectively be doubled by using an LED shunt to automatically switch to a secondary LED if the primary LED fails in a transition that takes less than 50 microseconds.
Following the impact, the masked manhunter grimly smiled to himself, appreciating the irony of being side-swiped even as he was trying to follow the rules. Sensors from ON Semiconductor in his seat indicated a drop in body temperature as he coolly ran through his options in his mind. Proximity sensors sent data to Alfred through a one-way channel as he shifted in his seat and turned the joystick a hard right in pursuit of Two-Face. An ON Semiconductor pressure sensor in his right tire indicated that a leak caused by the impact had self-sealed back to normal levels… but we digress. A more immediate concern was the fact that as he swung the wheel and diligently switched on his turn signal, the damage from the impact had rendered it inoperable.
Reliability and safety are paramount in vehicles. If the turn signal lights fail, signaling capability is extremely diminished. Due to this safety hazard, the turn signal lights need to be replaced immediately after failure.
To mitigate this problem ON Semiconductor has created intelligent headlight circuitry. In some headlight modules there is a daytime running light LED string next to the turn signal LEDs. Thanks to a novel scheme, this daytime running light string will blink instead of the turn signal, if the latter fails. This is all made possible by using the HBL5006 LED shunt in conjunction with the LEDs and monitoring circuitry.
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The HBL5006 is used in this headlight along with monitoring circuitry to blink the daytime running lights when a turn signal LED fails.
ON Semiconductor’s LED shunt portfolio is expanding to meet the needs of nearly any LED lighting application. The NUD4700 features a proprietary technology which allows for extremely efficient operation at high currents. The ultra-compact SOD-923 package for the HBL5006 is only 0.65 mm2 in size and is rated for 350 mA operation. LED shunts are simple to add in for enhanced reliability of any LED module, and thus manage to keep our most famous customer safe on Gotham’s streets.
On this occasion as the bat-EV turned to give chase to the arch-villain, Two-Face’s turbo-charged dragster accelerated off into the distance. The bat-EV could easily have followed and caught up but the caped one decided to fire one last volley and turn back into traffic, en route to his appointment. Promises must be kept, even in the face of a mocking enemy. Back at home, Albert heaved a sigh of relief and silently thanked ON Semiconductor for LED bypass shunts.
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Here the NUD4700 is running at 1.3 A with a case temperature measured by a FLIR camera of only 73.3 °C. The device is mounted on a test PCB and the crosshair of the IR camera is on the top of the device.
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