Case Studies
Chip Testing for Cordless Phones
A customer makes 900 MHz and 2.1 GHz portable phones using a specific chip that they purchase from a chip manufacturer. To ensure the quality of their product, the company tests each chip to avoid repair and debugging later on in the quality control department.
The chips that they are testing control channel switching. This function is used when the current channel becomes too noisy. They need to simulate data coming from the ADC on the phone and other user inputs, such as channel selection. To do this, they require a digital pattern of 24 bits and another device that can acquire 24-bit wide digital data coming out of the chip under test.
GAGE'S SOLUTION
Gage recommended a CompuGen 3250 and a CompuScope 3200. These cards are the best combination for digital testing. The CG3250 is a 32-bit pattern generator, capable of generating at up to 50 MHz with up to 8 MegaSamples of on-board memory for long pattern generation. The CS3200 is a 32-bit logic analyzer card with up to 2 GigaBytes of on-board acquisition memory.
The biggest advantage of these cards is the fact that they can be synchronized together with a common clock. The clock signal is generated by the CG3250, on its standard clock-out pin, and is used to clock the CS3200 using its standard external clock input. This ensures that they will not get unsynchronized data that could be interpreted as bad results by the analysis software.
The CG3250 and CS3200 have the same multi-pin connector. This connector mates with a 6-foot pleated foil cable that provides optimal transmission of high-speed digital signals. The pin assignments are the same on the CG3250 and CS3200 so that the cable can be used to directly connect the two cards for a "loop-back" test.
The customer must build his own applications because of their application-specific testing and software analysis. Accordingly, we suggested one of our CompuScope Software Development Kits as well as one of our CompuGen Digital Software Development Kits.
PRODUCT RECOMMENDED
CompuScope 3200 - 128MB
CompuGen 3250 - 8M
CompuScope SDK for C/C++ for Windows
CompuGen Digital SDK for Windows 95/98/NT
This application note is provided "as is" without any warranties of any kind, either expressed or implied, including but not limited to the implied warranties of merchantability or fitness for a particular purpose. Gage Applied Technologies further does not warrant the accuracy and completeness of the material contained herein. Gage Applied Technologies may make changes to this material, or to the products described in it, at any time without notice.
print this
email this
