View Single Post
Old 09-12-2014, 12:05 AM   #1102 (permalink)
Permanent Apprentice
Join Date: Jul 2010
Location: norcal oosae
Posts: 523
Thanks: 351
Thanked 297 Times in 213 Posts
To be perfectly honest, no. In fact, unless some trickiness is employed, I'm not sure the digital output can't be more quickly interpreted. Also, the Tamagawa version is used by Toyota - they have two in every Prius ( motor, generator ) So, the reliability of the concept and that IC is well proven.

My design should be cheaper, because both will need a custom PC board - that cost will be the same. Differences in circuit component cost are the main issues.

Actually, I found this out about 3/4 of the way through the AD app note: It makes perfect sense, as the IC has no power connections or heat sinks. They both need the power circuitry to drive the resolver. They also need the power supply to drive that amp. In other words, about 1/2 of the cost of the circuit that I am working on is that driver. It is the reason for the previous post. And - it doesn't go away with the AD chip or the Tamagawa chip; you're just confined to 10kHz or maybe 20kHz.

The other device that's a major cost in my previous design is the analog switch. The price of this comes down dramatically when it's spec'd for sub 5V, always positive. Power for this IC also becomes much easier.

So, in the end I have to deal with the same problems - just understanding the core nature of the problems is helping provide a much less expensive solution.
  Reply With Quote
The Following User Says Thank You to e*clipse For This Useful Post:
thingstodo (09-12-2014)