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by teleforce·6y ago·view on hn ↗
Most of the commentators in this topic are probably EE guys, may be I can find my old classmates here, hi guys:-)

Joke aside, AD is probably one of the most profitable companies with unprecedented monopoly on analog components and circuits business. Last week somebody mentioned about Visa and Mastercard duopoly in HN, but with this Maxim acquisition, AD is now the Visa and Mastercard combined while TI is the American Express.

To see how profitable AD is please check this article on the AD's 3rd generation transceiver chip and if you are not reading it, basically it's more profitable than drug [1]!

I am using every single versions of this AD's transceiver chip for my work, now it is in the latest 6th gen. Suffice to say if you're building 5G transceiver you will need AD's 5th gen transceiver. It's probably not an exxaggeration to say that ITU radio/wireless cellular standards' bandwidth actually following the AD's transceiver chips generations since 5G system can be built by the 5th gen chip but not the 4th gen chip (it's for 4G). The closest competitors are transceivers from LT (already acquired by AD) and the Lime Microsystems from Cambridge, UK.

[1]https://zeptobars.com/en/read/AD9361-SDR-Analog-Devices-DAC-...

2 comments
How did you come to the conclusion AD is hugely profitable ?

Thier ROIC is 6.7% https://www.gurufocus.com/term/ROIC/NAS:ADI/Return%2Bon%2BIn...

This is below the SP500 ROIC.

Visa / Mastercard ROIC is >20%

Even with Lime Microsystems, their chip barely functions compared to the equivalent ADI part. Sure, it's nameplate specs are nice but it the dynamic range is crap and the EVM barely passes the LTE spec.

Even worse is that basically the only product using the chip is Lime themselves so trying to spin your own product would be a nightmare. ADI has a nice eval board and reference design for their chips and you can control it using the lib-iio framework which is built into mainline linux.

I really wanted Lime to succeed here, because we could all use the competition, but man, that Lime chip really is absolute crap. It has dead zones all over the spectrum where the LO PLL won't lock, even within the temperature spec. [1]

I returned my LimeSDR Mini after a frustrating weekend and bought a USRP instead, which uses the AD chip, and there's really no comparison.

This is one reason why I said in another comment that I thought it'd be difficult for a fabless upstart to complete on a complex / high-performance design like an ADC. The chip Lime designed is an absolute monster -- it has multiple ADCs, DACs, filter banks, switches, oscillators, PLLs. If any one of them isn't perfect, the whole design is shot. I'd still like for them to succeed, but when you're selling a hundred dollar IC, it really does need to be flawless.

[1] https://discourse.myriadrf.org/t/new-limesdr-mini-loopback-t...

Those deadzones are horrible. Also, the calibration routine is absolutely broken.

For example, when userspace requests a certain TX gain, the chip does some calibration black box magic to determine the best way to distribute that gain across the internal amplifies. Nothing special here, the AD9361 does the same thing. The Lime chip will inexplicably fail the calibration but __will continue to operate__. If the PLL didn't lock, the chip sees something dumb like the loopback being down at -45dBFS so it cranks the gain on all of its internal amplifiers to __correct__ the loss. This results in one or more of the internal amplifiers saturating and you end up with horrible intermod. I was seeing -10dBC ACPR on a simple 1MHz QPSK signal. Sure, you can save off good calibrations or do it by hand, but if the simple loopback cal doesn't work and won't tell the user, the chip is irremediably broken.

>using the lib-iio framework

You say this like it's a good thing. It's one of the most generic, do everything gigantic overhead drivers I've heard of. On the pluto it limits things to 4 MS/s when without that libiio overhead it can push double that over the USB interface. I suppose things might be different with top of the line AD transceivers.

You're right, it's not great for actual products. I was talking more about prototyping and debugging. It's super nice to be able to just do a "cat /sys/bus/iio/.../.../out_voltage1" or build a simple tool that does that for you.
AMEN! I thought it was good for prototyping and on-off devices but I’ve been appalled at how many products ship with it