ATS460: External Clock Upgrade

While the ATS460 features low jitter, high reliability 125 MHz and 100 MHz oscillators as sources of the timebase system, there are occasions when ATS460 has to be synchronized to an external clock source. ATS460 External Clock option provides an SMA input for an external clock signal, which can be a sine wave or LVTTL signal. In order to operate the ADC under optimal conditions, the user must set the appropriate frequency range for the external clock being supplied. The following ranges are supported:

Fast External Clock: 80 MHz < fEXT < 125 MHz
Medium External Clock: 10 MHz < fEXT < 80 MHz
Slow External Clock: fEXT < 10 MHz

The active edge of the external clock is software selectable between the rising or falling edge.

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  • Provides 3 modes of External clocking:
    • Fast External Clock
    • Medium External Clock
    • Slow External Clock
  • Selectable 50 Ohm or 1 kOhm input impedance

Powerful Slow External Clock

ATS460 uses ADC converters that cannot operate below 10 MHz clock frequency. For customers who have clocks that are slower than 10 MHz, AlazarTech has designed the powerful Slow External Clock.

Slow External Clock must be a 3.3 Volt LVTTL signal. Sine wave or other types of signals are not allowed.

In this mode, the ADCs run at 125 MHz internal frequency, but the hardware detects a rising (or falling) edge of the incoming Slow External Clock and latches one sample point for each edge. This results in a sampling jitter of ±8 ns, which may or may not be acceptable in a particular application.