This optional upgrade allows ATS9373 to perform analog to digital conversion based on an external clock signal. This upgrade contains all the features of ATS9373: External Clock Upgrade (ATS9373-005), but also guarantees that Fast External clock will work down to 100 MHz frequency.
Two software selectable modes of external clocking are supported: user supplies a 10 MHz reference clock and the on-board VCO locks to it; or Fast External Clock whereby ATS9373 takes one (or two in DES mode) samples for each cycle of the user-supplied clock. Fast External clock frequency must remain in the specified range of 100 MHz to 2 GHz.
What is Screened External Clock?
The ADCs used on ATS9373 have a “minimum clock frequency” specification of 300 MHz, i.e. if the external clock signal is lower than 300 MHz, the ADC may not be able to make proper measurement. Typical problem is that user will see glitches in the output data. Many customer applications need the ATS9373 to work with external clock frequencies lower than 300 MHz.
Fortunately, we have seen that many ATS9373 work perfectly down to 100 MHz clock rate. We have developed a process by which we can “screen” the ATS9373 board for external clock operation down to 100 MHz, i.e. select ATS9373 that works down to 100 MHz clock frequency.
If customer purchases the screened External Clock Upgrade, we will test the ATS9373 at external clock frequency down to 100 MHz to make sure that it works before shipping it to the customer. If the ATS9373 we are testing does not work down to 100 MHz, we will not ship it to the customer and use a different unit that does work down to 100 MHz. The screened option (ATS9373-006) includes ATS9373-005, i.e. if you purchased the screened option, you do not have to purchase the other.