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Schematic RC time constant: 1K * 1u = 1ms, Vc = V1 * [1 – exp(-t/RC)] When t = 1RC, Vc = 0.63V1 = 3.15V; When t = 2RC, Vc = 0.86V1 = 4.30V; When t = 3RC, Vc = 0.95V1 = 4.75V; Recommendation: A tool for calculating time constant Device information: Device Model Element Signal source V1 VPULSE/ SOURCE Resistor R1 R/ ANALOG Capacitor C1 C/ ANALOG GND 0   Signal source description: V1: Starting voltage V2: Pulse voltage TD: Delay time, set 1ms here for easy observation TR: Rise time, set 0.5us here TF: Fall time, no need to set PW: Pulse width, no need to set, that is, the pulse width is unlimited PER: Pulse period, no need to set Simulation Results Simulation settings: Add Trace: Add Toggle Curse, Mark Label, Text Label: It can be seen that one time constant corresponds to a voltage of 3.1612V; two time constants correspond to a voltage of 4.3232V; three time constants correspond to a voltage of 4.7510V, which is similar to the theoretical calculation.

As a hardware engineer in electronic design, level conversion is a topic everyone must face. The main chip pins use 1.2V, 1.8V, 3.3V, etc., and the external interface chip uses 1.8V, 3.3V. , 5V, etc. Because the level does not match, level conversion is necessary. Every engineer has his own set of conversion schemes. Today we will summarize the six level conversion methods, and summarize various advantages and disadvantages to avoid unnecessary troubles in the design process. Note : All links in the text are pages or posts explaining  related knowledge. Hope you don't mind! and don't miss the great content! All of them are from an excellent website called Apogeeweb which can be very helpful for learning about electronics and semiconductors. Level conversion method Below we will evaluate from the five dimensions of speed, drive capability, leakage current, cost, and the number of channels. 1) Transistor level conversion method; 2) Dedicated level conversion chip; 3) Current-lim...

1. Readers Suitable For This Article First of all, this article is suitable for those rookie-level electronic enthusiasts , those who want to use their soldering iron to solder some gadgets or buy some electronic modules to realize their interactive creativity. This article is not suitable for professional-level readers. In order to make it understandable for enthusiasts, it is inevitable to adjust some contents that do not affect the principles, so don't be so serious if you see some "mistakes". In addition, the vast majority of Datasheets are in English, so this also requires readers to have a certain level of English reading. Finally, a complete understanding of a Datasheet is actually a fairly superb skill. This requires not only deep knowledge of electronics, IC manufacturing technology, circuit design, but also a variety of professional knowledge. Here, the author can only make a rough outline introduction, at least let the reader have a basic concept in future appl...