16 Aug
2015
16 Aug
'15
4:55 p.m.
I believe that is true, it is a SAR type of ADC. That is an import
piece of information there concerning reading the ADC too fast.
Because I have one instrument that is working properly I can use that as
a baseline to look at how fast the ADC is being pinged on.
This gives me something to go on.
On 8/16/2015 12:56 AM, dwight wrote:
Most of these older module use successive
approximation
converters. If you read them too fast, you'll only get a partial
conversion.
A number of manufactures made these modules. Analog Devices,
Harris, Beckman and several others.
Dwight
From: ard at p850ug1.demon.co.uk
To: cctech at classiccmp.org
Subject: RE: Analog to Digital Converter
Date: Sat, 15 Aug 2015 16:40:40 +0000
I have a number of laboratory instruments that
are from the 1990 time
frame. They produce digital data that is the digitized signal from a
detector, the data can be from 512 to 65K samples long. The ADC used in
these instruments is a 16bit 100ksample/sec design. The ADC is in a 3
by 4 inch metal box with a row of pins on each long edge.
[...]
What is inside the box? Is it a hybrid circuit?
I came across somewhat similar looking ADC and DAC modules in an I2S image
display system. These were flat metal cans with pins on the bottom, going into
individual sockets on the PCB.
In that case the can could be opened up quite easily (I think just a couple of points
to unsolder. Inside was a PCB _stuffed_ with components, including several possibly
custom metal-can ICs (in the case of the ADC I susect fast analogue comparators).
Have you tried to open your module? It may not be potted.
-tony