Amazon Echo Flex: Microphone mute button appears to be real and functional

#1

Post by picture » Tue, Jan 12, 2021, 4:26 AM UTC

Amazon Echo Flex: Microphone mute button appears to be real and functional
electronupdate.blogspot.com

Re: Amazon Echo Flex: Microphone mute button appears to be real and functional

#2

Post by teruakohatu » Tue, Jan 12, 2021, 4:52 AM UTC

Tldr; it is real.

Re: Amazon Echo Flex: Microphone mute button appears to be real and functional

#3

Post by colejohnson66 » Tue, Jan 12, 2021, 4:53 AM UTC

Nice to see electronupdate here. For those who don’t know, he also has a YouTube channel[0] where he does teardowns of random ICs. It’s quite interesting seeing the die shots. I’m assuming this post is a continuation of his “part 1” post/video from a week and a half ago[1] about the Echo Flex.

His videos are definitely not scripted (and barely edited), which can be off putting to some (hearing “umm”s among other things), and he doesn’t go into the detail that Ken Shirriff (@kens) does, but they’re interesting nonetheless.

[0]: https://youtube.com/c/electronupdate

[1]: https://youtu.be/gYPLunFMIEI

Re: Amazon Echo Flex: Microphone mute button appears to be real and functional

#4

Post by markdown » Tue, Jan 12, 2021, 5:02 AM UTC

teruakohatu wrote: post #2

Tldr; it is real.

Thanks. Annoying that clickbait titles are allowed here.

Re: Amazon Echo Flex: Microphone mute button appears to be real and functional

#5

Post by sircastor » Tue, Jan 12, 2021, 5:03 AM UTC

This is a really great breakdown of what’s going on in device. I really appreciate the case removal to look at the inside of the chips, as well as the general explanation of the circuits involved.

Re: Amazon Echo Flex: Microphone mute button appears to be real and functional

#6

Post by colejohnson66 » Tue, Jan 12, 2021, 5:05 AM UTC

markdown wrote: post #4

teruakohatu wrote: post #2

Tldr; it is real.

Thanks. Annoying that clickbait titles are allowed here.

The rule is there not to prevent clickbait, but to prevent editorializing the title when it’s posted. The reason is editorializing inserts biases and possible wrongs (unintentionally).

However, it is clickbait, by definition, but it’s not clickbait. If it was, I’d expect: “You’ll never guess what your Echo Flex does when you do this one thing!”

Re: Amazon Echo Flex: Microphone mute button appears to be real and functional

#7

Post by jojobas » Tue, Jan 12, 2021, 5:15 AM UTC

The implication is that the microphone emits completely no signal without power and doesn't have any capacitor to last even a few seconds.

Surely the most valuable data is just after the mute is turned on?

Re: Amazon Echo Flex: Microphone mute button appears to be real and functional

#8

Post by kevin_thibedeau » Tue, Jan 12, 2021, 5:15 AM UTC

The parallel flops are probably hardening against bit flips from ESD events. There aren't any other active protection devices and phantom flips probably showed up at some point during testing of earlier prototypes.

Re: Amazon Echo Flex: Microphone mute button appears to be real and functional

#9

Post by osamagirl69 » Tue, Jan 12, 2021, 5:33 AM UTC

Very nice writeup, I love the combination of fun writing style and hand drawn schematics with things quickly escalating to decapping chips.

Also nice to see that the led is a real one, even if the micro does have the ability to override the mute switch... I guess the 80's scifi movies with red glowing eyes to indicate the 'evil' subroutene was activated got it pretty close!

Re: Amazon Echo Flex: Microphone mute button appears to be real and functional

#10

Post by spicybright » Tue, Jan 12, 2021, 5:39 AM UTC

kevin_thibedeau wrote: post #8

The parallel flops are probably hardening against bit flips from ESD events. There aren't any other active protection devices and phantom flips probably showed up at some point during testing of earlier prototypes.

I'm honestly surprised they went that far, and happy they did.