Nuts About Neon
31-07-2023A Deep Dive Into The Bright Lights of Neon
Everyone wants Bluetooth. And this is our take on a quality Bluetooth receiver. Neon is a wonder of a small device. It's deceptively small and simple, but inside there's a large assortment of great features, creative engineering, and downright "that shouldn't be possible" type stuff. So let's dive right in:
Here's the guts of Neon. It's a single, multi-layer PCB assembly. There are two PCBs layered together to get us the space inside we need. The upper PCB contains the main control ICs, the lower PCB contains the big power and analog stuff. Let's start with the back... (the side opposite the buttons).
The back contains most of the critical ICs and circuitry. The Qualcomm QCC3034 resides here, as does the Qualcomm RF Amplifier. This is the main brains of the device, where all the decoding, Bluetooth protocol, and overall control resides. It's also where we spent months writing the embedded firmware that allows us to do that magical dual source thing that Neon does. No, that's not a standard feature! In fact, when we showed that functionality to a few Qualcomm RF engineers at a trade show, they wanted to know how we did it - because none of their chips are supposed to be able to do it. No, we didn't tell them, and no we're not going to, either.
The back also contains the amplifier. This is the discrete audio amp that cranks out that amazing 140+ mW into 32 Ohms. A full 2.2Vrms output is available here - enough to run just about any headphone on the market, It backs that voltage up with 100 mA continuous current capacity, so you're not going to clip even with low impedance cans. And the power supply is attached directly to the amp, with thick traces on the inner layers of the main PCB, so we can pull all the power from the battery that we need, with no worries.
The last few things on the back are the jacks. The 3.5mm TRRS and the USB C connector. The 3.5mm is obvious - that's where you plug in, and it contains a switch that turns the entire unit on when you plug in. The USB C? That's for charging the battery. That's it. Yeah, seems kind of wasteful, but it's an easy connection and we have a lot more USB C products coming, so - why not?
NOW - on to the front! This is the side you're most familiar with - the side with the buttons. They're arrange logically, directly under the molded plungers. The volume up, triple button, and volume down are all small snap disc buttons. They need to be snappy, and since there's really no timing information with them, we can use snap activation buttons.
Next, we have the LEDs. There's a blue and green LED mounted side by side. These live right under the LED light pipe, and are lit up by the QCC3034 based upon operating mode. Yeah, they're tiny - about 1.6mm x 0.8mm! But they are high efficiency units, and we use resistive loading to adjust the intensity so we avoid any ugly audio issues from PWM for LED brightness control.
At the bottom, we see the Source Button. This is the coolness of Neon - making and maintaining two connections to sources. This button needs to be reliable for timing, so we use a real mechanical plunger type button. It's a LOT more money than a snap button, but that's the price you pay for precision.
Over to the top right, we see the high gain chip antenna. We use a discrete antenna here for maximum output AND spherical radiation pattern. It's why Neon works for 10+ meters without an issue.
Lastly, we see the power supply. These regulators produce the voltage rails from the battery as needed, but we use ultra-low noise units with less than 100 nV of noise, so we keep everything clean and tight.
And there you have it! Neon's guts, spread out for you to see. All the fun parts, how we laid it all out. The back has the battery sandwiched on top of it, the cutout at the top contains the microphone, and we pop it into our high durability thermo copolymer chassis with snap closures to keep it nice and secure. Neon - not just a pretty face and stellar performer, it's got great guts, too!
BONUS: for reading this intro to Neon, you can get 10% off the price of Neon using the discount code NEONGUTS. Good through August 31, 2023! Save 10% by showing you've read this informative post!