#194 External Watchdog Panelised PCB and Testing (plus giveaways)

Prevent microcontroller latch ups and hang ups with this circuit re-setter.
JLCPCB Only $2 for PCB Prototype any colour https://jlcpcb.com/
Special offer for SMT assembly.

We discussed the breadboard circuit in video #190 (https://youtu.be/wcRuVxXlEKw), but here we have the finished product, including the panelised PCB from JLCPCB together with some testing using a signal generator and an oscilloscope.

The 555 is the most popular integrated circuit ever manufactured. As of 2003, it was estimated that 1 billion units were manufactured every year. And we are using it this week in this timer watchdog that power recycles your Arduino (or other µController or module of choice) if it hangs up.

00:00 Welcome Back!
00:43 What is an external watchdog timer?
01:14 JLCPCB services
01:50 Circuit diagram
04:39 PCB Design
09:39 Testing with a waveform generator
14:04 What is this tape?
14:40 Panelisation discussion
18:06 PCB Giveaway (read the pinned comment FIRST please)
20:30 Resources in my GitHub

### List of all my videos
(Special thanks to Michael Kurt Vogel for compiling this)
http://bit.ly/YouTubeVideoList-RalphBacon

### INFORMATION

Elektor Magazine Article (Wolfgang Borst)
UK: https://www.electronics-lab.com/free-elektor-circuit-ne555-watchdog-timer/
DE: https://www.elektormagazine.de/news/kleine-schaltungen-neu-aufgelegt-watchdog-mit-555-folge-6
https://www.elektormagazine.com/news/small-circuits-can-do-the-job-an-ne555-watchdog-timer-part-6

555 timer IC
https://en.wikipedia.org/wiki/555_timer_IC

### HARDWARE
Surface Mount 555 chips, less than $1 for 10 pieces (plus shipping)
https://s.click.aliexpress.com/e/_Bfjexh5a

10pcs NE555 NE555P NE555N 555 Timers DIP-8
https://www.banggood.com/10pcs-NE555-NE555P-NE555N-555-Timers-DIP-8-TEXAS-p-1069802.html?p=FQ040729393382015118&utm_campaign=25129675&utm_content=3897

CJMCU-4599 Si4599 N and P Channel 40V (D -S) MOSFET
banggood.com/CJMCU-4599-Si4599-N-and-P-Channel-40V-D-S-MOSFET-Expansion-Board-Module-p-1350610.html?p=FQ040729393382015118&utm_campaign=25129675&utm_content=3897

10pcs 2N7000 N-Channel Transistor Fast Switch MOSFET TO-92
https://www.banggood.com/10pcs-2N7000-NChannel-Transistor-Fast-Switch-MOSFET-TO92-p-924050.html?p=FQ040729393382015118&utm_campaign=25129675&utm_content=3897

If you like this video please give it a thumbs up, share it and if you're not already subscribed please consider doing so and joining me on my Arduinite journey

My channel, GitHub and blog are here:
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https://www.youtube.com/RalphBacon
https://ralphbacon.blog
https://github.com/RalphBacon
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Видео #194 External Watchdog Panelised PCB and Testing (plus giveaways) канала Ralph S Bacon