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John Larkin[_3_] John Larkin[_3_] is offline
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Default Thermometer Code Chip

On Sun, 12 Apr 2015 01:15:58 +0200, Dimitrij Klingbeil
wrote:

On 10.04.2015 06:20, rickman wrote:
On 4/4/2015 3:40 PM, Tim Williams wrote:
"rickman" wrote in message
...
Flash converters are the only choice for anything above around
1-2 MSPS last time I looked hard. Maybe they are pushing towards
10 MSPS with SARS and SD converters. But for anything higher a
flash converter is the only choice.

When did you last look? Two decades ago?

All the ones I've seen (within say 5 years) from about 20 to 500
Msps and 8+ bits are pipelined SAR. Usually with terrible INL for
the higher bits versions, but that reflects their usage: AC
circuits, radio (SDR), ultrasound, etc., where low DNL is
priority.

Often, they're also in a series, so you get like, 65-80-110 Msps
and 10-12-14 bits. Likely they use the same configurable die for
everything in that series, and burn some fuses during test to
implement the highest spec the chip meets.


Can you offer a few part numbers?


Pretty much everything 10(+) bit-ish and high-speed from Analog devices,

like the AD9257 or whatever else that starts with AD92... or AD96...

Dimitrij




The LTC2242 family goes from 125 MHz/10 bits up to the one we use,
250/12. Pipeline delay is 5 clocks.

Here's one on a board, 12 bits of LVDS into an Altera FPGA, at 250
MHz.

https://dl.dropboxusercontent.com/u/.../ESM_rev_B.jpg

We are seeing less than 1 LSB of RMS noise. That was shocking,
especially considering all the switching supplies an inch or so away.



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John Larkin Highland Technology, Inc
picosecond timing laser drivers and controllers

jlarkin att highlandtechnology dott com
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