(Intro Sound) - [Jason] So, to start off with, you know, a Fitbit style wearable, you know, I'm thinking something
that is relatively narrow, needs to be comfortable
to wear 24 hours a day, usually has a very sleek form factor to make sure that it's, you know, as least noticeable as possible. As a result, the size of the product instantly makes me think, well, if I want to use low frequency, I will probably need to have a
coil that's relatively thick, has a lot of windings, in order to get the necessary
electrical characteristics to get efficient power transfer. There are better options. RF, NFC, and high-frequency both utilize, in the case of RF, you know, a Bluetooth antenna, something
similar of that nature where it could be printed
on a flex substrate and NFC and high-frequency
which, you know, the coils are on the range of nanohenries, which means one or two turns on a coil as opposed to qi, which
requires microhenries which means, you know,
tens to twenties of turns. So, from my thought process,
RF, NFC, and high-frequency both allow you to integrate wireless power into this specific industrial design while maintaining the
electrical performance that you're looking for. - [Speaker] Great. And so, when we get to question two, Jason,
the coil to coil distance and how many receivers need to charge, we see that NFC and high-frequency
are still tracking okay, but what's going on with RF to
make that a bit of a concern? - [Jason] So with- with RF, the current FCC certified RF transmitters have a max output power
of about 1.5 Watts. With RF, according to Friis equation, every time you double the
distance from the transmitter, your power transfer
capability will drop by half. So, if you look at these
products that, you know, usually require on the order of, you know, hundreds of milliwatts to about 1.5 watts. With RF, you start to get really limited with the ability to charge
your device on the go. If there was an RF
infrastructure, you know, having RF chargers placed everywhere, you might be able to get
enough trickle charge throughout the day to
support your product. However, you know, when you're thinking about fitness wearables, such as a Fitbit, you're out and about, you're outside, you are running, you're biking. So, the ability to charge
your device reliably becomes very difficult and in order to get that
quick charge ability, you would essentially need to
place your wearable right next to the RF transmitter,
which kind of, you know, is impractical and kind
of eliminates the purpose of RF charging. So, from that case, you know, we have the ability to
transfer power to the wearable in the ranges that we're looking for, but from a use case, NFC and high frequency
make a lot more sense. You have a higher power
capability, you know, up to three watts with NFC and more with high- with high frequency, which gives you that same user experience. And now, you know, people
are pretty accustomed to the- the apple watch experience, right? Where you have the little
dongle that attaches to the back or you have a cradle where
you place your device into. You want to get that topped off, You want to get it charged, and you want to be on your way, and you don't want to
have to worry about it. That's why I give NFC and high-frequency the plus in this category because we can charge a device quickly and it also allows the
same user experience people are currently used to. - [Speaker] Perfect. So, when we move to question three, we start to see even a little
bit more separ- separation of- of a preferred method here. Does the product need
data transfer capabilities greater than 10 kilobits per second? First, why would a wrist wearable
need something like that, and since it does, you know, why- why are we seeing some clear- clear winner in the pack here? - [Jason] So, you know, the apple watch has wireless charging in it. However, if you remove one of the straps, there is a hidden debug
port off to the side. So, if you truly want to
make a wireless device, you need to be able to
provide a data channel that would give, you know,
developers, debuggers the ability to enter low level, let's say, programming, or, you know, communication with the device without having to rely on the battery or the other
radios inside the device. You know, if you're
picturing a situation where your watch is dead and you're
trying to debug something, you're still gonna need
to charge the device up. So, in this case, starting with RF, you know RF has the ability
to transfer data, you know? It's based off of similar frequencies like wifi and Bluetooth. We have very high data capabilities. However, in a situation where you are in a dead battery situation, you just don't have
enough power to be able to boot up the system and
provide any meaningful data back and forth. High frequency, you can supply the power, but like I mentioned earlier, with the inbound communication, you know, we're kind of limited to
about 10 kilobits a second. That might be enough for some
basic charging information going back and forth, but if you're trying to, you know, do UART or send some kind of higher level data, the speeds aren't really there. With NFC, with the ability to transfer up to 848 kilobits a second, you know, we have been able to design
systems that essentially are over their UART. So, we are giving developers and let's say product designers the ability to keep those
necessary low level functions enabled while completely
making the device sealed. So, that's why I give
NFC the benefit here, because it has a higher
data transfer capability that we can use to address
some of the issues that, let's say, product designers have had because they need to keep a debug port attached to their product. - [Speaker] Great. And so on question four,
we see a little bit of a question mark, with regards
to power level needed to- to- to- power and charge
the device on the RF side. Why is that Jason? - [Jason] So like I mentioned
a little bit earlier with RF technologies, your power from the transmitter to the receiver drops by two every time
you double the distance. So, in the case of RF,
you know, the- the idea is to be able to walk into a room and deliver power to your device and keep it charged up. Unfortunately, that's on
the order of milliwatts if you're walking through a room. Because of that, I give it- I give it a minus. The infrastructure's not there yet, the locations where these
wearables are being used probably will not have an RF power transmitter. So, you can only expect
a couple milliwatts unless you place this device directly in front of the transmitter. So, I give it a minus from a use case. and from a cost perspective. These transmitters tend
to be a lot more expensive because they have to be able to supply power to an entire room. NFC and high-frequency both,
you know, are closely coupled and have the ability to, you know, deliver the necessary power level up to three watts. That is more than enough
for a lot of these products. So, that's why I give NFC and
high-frequency the thumbs up in this specific question. - [Speaker] Sure. And for question five, you've mentioned a couple times that RF doesn't have the infrastructure there and we had the same thing
come up with the laptops for high-frequency, but you've given a real positive mark here
for question five for NFC. Why is that? - [Jason] So, in 2019, the NFC form ratified the WLC
wireless charging standard for NFC. There are multiple people
currently developing, the Universal Stylist
Initiative is using NFC as its main tr- main standard for wireless power transfer. In addition to that, you know, there are rumors that
mobile phones are also going to start having NFC
charging enabled inside of them. So, from that aspect, from a
charging infrastructure aspect, NFC seems like the clear path forward here because the infrastructure
is being developed and being creative. In addition to that, NFC also
has its data infrastructure. So, the same coil that
we'd be using for NFC, charging your device can
also be used for tap to pair, potentially tap to pay, and other user benefits that
come from that data link. Based off that, NFC makes
the clear path to me, whether it is going to be
something that requires kind of a proprietary ecosystem or utilizing the entire
NFC infrastructure, it gives developers the
options that they need to give the necessary user
experience they're looking for. - [Speaker] Sure. And
because of some of the similarities in terms of
question one and question two and even question three, another category like
smart glasses really comes into play here as a kind
of map, similarly to this. We're using our NFC- Nueva
NFC development platform on both wrist wearables and smart glasses based on these product constraints and coming up with some
really exciting solutions. (suspenseful music)