4 ms·
The cheapest ones at Digikey are going for 10 cents (compared to 35 cents for the cheapest small microcontrollers [PSOC or a 10F200]). So I guess they still ha
by swamp40 11y ago
The cheapest ones at Digikey are going for 10 cents (compared to 35 cents for the cheapest small microcontrollers [PSOC or a 10F200]).
So I guess they still have some use.
Probably sell mostly to hobbyists, universities and old designs though.
- mrob 11y agoThe microcontroller doesn't need the external resistors and capacitor. If the 555 circuit needs a big capacitor then the microcontroller circuit could be cheaper.
- pjc50 11y agoThe microcontroller does, however, need a decoupling capacitor and the inclusion of a program in manufacturing. It may also be pickier about power supplies.
- mrob 11y agoTrue, but ideally the 555 should have a decoupling capacitor too, and the decoupling capacitor is very small and cheap.
- dheera 11y agoHobbyists hardly use these things anymore, because they require all that external stuff -- resistors, capacitors -- before you get what you want out of them. They're not self-contained. These days you can just program a PIC or something, drop it on your broadboard, and you get whatever signal you want out of them with software, without any components besides the chip itself, and maybe a quartz crystal if you want better accuracy (although I really wish they'd package a crystal inside the DIP as well to make it even more self-contained).
- beeforpork 11y agoThe DS3231 RTC clock chip indeed has an accurate crystal oscilator inside the package, so, yeah, put em in an AVR why not!