What is RTC?

Crystal oscillator

Quartz Oscillator 3225 20M OSC

Introduction: This article mainly introduces what RTC is, don't understand what it is, Dongdong's children's shoes, let's learn it, it is very upright~~~

1. What is RTC --Introduction

RTC , English full name: Real-time clock, Chinese name: Real-time clock, refers to the electronic device that can output the actual time like a clock, usually an integrated circuit, so it is also called a clock chip. The real-time clock chip is one of the most widely used consumer electronics products in daily life. It provides people with accurate real-time time, or provides an accurate time reference for electronic systems. Currently, real-time clock chips mostly use a higher precision crystal oscillator as a clock source.

2. What is RTC - advantages

The RTC can provide a stable clock signal for subsequent circuits. A system without a real-time clock can also calculate the actual time, but using a real-time clock has the following advantages:

1) Low power consumption (extraordinary when using auxiliary power)

2) Let the main system handle more time-sensitive work

3) Sometimes it is more accurate than other methods of output

The GPS receiver can reduce the time it takes to power on if it is paired with a real-time clock. It can compare the time it gets to the time it was last received. If the time difference between the two is within a few hours, the last ephemeris can still be valid and can be used normally.

3. What is RTC - performance indicators

The real-time clock typically has a backup power source that can be used to continue calculating time when the main Power Supply is powered down or unavailable. Its main performance indicators are divided into the following categories:

Control method: two-wire system, three-wire system, four-wire system.

Crystal oscillator: divided into built-in crystal oscillator and external crystal oscillator.

Current consumption, time fine-tuning range, time accuracy and whether there is TTF function.

4. What is RTC --function

The most important function of RTC is to provide the calendar function in 2099. For time, no matter whether it is fast or slow, the matching capacitor plays a very important role in the peripheral device of RTC. It can properly correct the relationship between crystal and RTC. Match the problem. In particular, RTCs such as the H1208 have built-in matching capacitors, which ensures the consistency of RTC accuracy. Some RTCs do not go faster, and some go slower.

Expand reading:

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