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A digital speedometer is a device that gives the current speed of a moving object. It can generally be seen on motor vehicles. Like older models, this device is also essential in vehicle operation as it gives the person controlling the vehicle / machine an awareness of their speed so that they can maintain the correct speed and avoid colliding with something in road.
The digital speedometer has a couple of advantages over its ancestor, the analog speedometer. One of the advantages is that digitals produce more accurate and reliable readings. This is because digital speedometers use speed sensors that actually read the speed of the vehicle’s movement and then send the results to the speedometer’s microprocessor, which is responsible for the display. Another advantage is that digital speedometers show the speed measurement in numbers, which is much more legible than the clock-like display of analogs. Drivers suffering from impaired vision would surely prefer digital ones, as they would no longer need to look at pointers and somehow unclear lines between digits on the clock-like display.
There were not many revisions on the digital speedometer. In fact, only a couple of new parts have been added for it to do its job properly. As I mentioned in the previous paragraph, you have and always should have a microprocessor that comes with an IC1 and an IC3. The IC1 acts as a mini computer and regulates the speedometer voltage, while the IC3, a mini inverter, provides many special functions such as latch, reset functions, and trigger signal functions. As for the speedometer display, a 2-column LCD mini-monitor is provided which can display up to 16 characters.
Outside of the mini-computer system is the IC4 and a detector that measures the rotational speed of the wheels. A magnet is attached to a wheel to detect. It will pass through the detector once for each rotation of the wheels; each rotation equates to a single detection. The detector will generate pulses depending on the number of detections it has made (the ratio is 1: 1). The pulses will then be calculated by IC1, after which the digits indicating speed (miles or kilometers) per hour will appear on the LCD screen. An interesting feature has also been added to the latest models, namely the ability to calculate how far the vehicle has traveled from the last time the engine was started to the last time it was stopped.
It is a fact that both analog and digital speedometers cannot give the exact speed at which a vehicle is operating. However, the digital speedometer has the advantage over analog in terms of accuracy, as it is the “upgrade” from its predecessor. They may have some differences, but they share a common purpose, namely to guide the driver for safe driving.