BY DUANE MATTERN
Lease Versus Purchase
There are many equipment leasing companies out there. Unfortunately, they rarely list prices or the details of their
equipment on their websites. Also, most of the logic analyzers for lease are the big expensive monsters with lease prices
in the order of $500.00/month. My requirements were only for 15 channels, possibly 12 months, and under $1,500.00.
This pretty much ruled out the lease option — at least for the full-featured logic analyzer. So, I ruled out leasing and
went shopping.
Shopping
Where do you do your shopping? When I’m looking for electronics, I typically look in past issues of Nuts & Volts
Magazine before doing a search on Google. Once I have a product name, I’ll look in Google’s Groups to see if anyone
has made comments (good or bad) about the equipment. I have seen a number of ads for PC-based electronic
equipment that uses USB for communication. In fact, I have been involved with the development of such equipment
using the ICs from FTDIchip.com From ads in Nuts & Volts, I knew that USB-based logic analyzers existed, so I
started my Google search with the keywords, “USB Logic Analyzer.” That immediately brought up a number of items
that I have summarized in Table 1.
Product Selection
All of the products in Table 1 would probably work for my application. From a software point of view, USBee looks
neat because it has an application programmer’s interface, which could be used to expand its functionality. However,
it only had eight channels and I needed 15. Also, it uses USB 2.0, which my PCs support, but I have not yet used it.
The equipment from Link Instruments was pricey when compared to the other devices. I ruled out the Ant16 because
I thought the buffer size of 2,048 samples/channel wouldn’t support my requirement of collecting data for several
seconds.
I ended up selecting the DigiView DV1-100 device over the Janatek Lu LA-USB device because of the price and
also because I hoped that the DigiView’s hardware data compression would allow me to look at long time sequences
of the switching data. Also, Tech Tools was the vendor for the DigiView equipment and I’ve done business with them in
the past.
Table 1. Summary of USB Logic Analyzer Search
Name
# of Chs
Buffer Size
Sample
Rate/ch
Comments
Price
Ant8/Ant16
16
2,048 samples/ch
500 MSa/s
500MHz Async,
100MHz sync
$299.00
Tech Tools DigiView
18
132,000 samples
100 MSa/s
w/data compression
$495.95
Link Instruments
LA-4540
16
24
8@512k, 8@256k
16@256k, 8@128k
500 MSa/s
250 MSa/s
various models
$2,200.00
Janatek Lu LA-USB
16
1,048,000 samples/ch
200 MSa/s
$750.00-$1,100.00
USBee (a number of
different models)
8
1 million samples up to
available PC memory
24 MSa/s
USB 2.0 for max. rate
$395.00-$895.00
JULY 2004
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