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Re:Silicon die teardown: a look inside an early 555 timer chip by altcognito on Tuesday January 25, 2022 @12:29AM (#30068468)
How do you get such a wide range of times with such a tiny capacitor? I imagine there is some magic with multiplying this effect across multiple caps?
Re:Silicon die teardown: a look inside an early 555 timer chip by kens on Tuesday January 25, 2022 @01:31AM (#30068839)
For a short delay, you use a small resistor and a small capacitor. For a long delay, you use a large resistor and a large capacitor. The result is that it supports "timing from microseconds through hours." The timing resistors and capacitors are external, so you can select whatever values you want for your application.
Re:Silicon die teardown: a look inside an early 555 timer chip by bonzini on Tuesday January 25, 2022 @03:02AM (#30069377)
It's not necessarily tiny. You could use an electrolytic capacitor with a capacity of a few millifarads, for example. However, the tolerance of larger capacitors is larger (usually 20%, and up to 50%) so that quickly becomes expensive. It's more likely that you'll generate a 10 second or less pulse with the 555 and then make it longer using (for example) T flip-flops. A single 744040 ripple counter IC for example can divide the output by up to 4096.