Acqiris U5309A User Manual page 52

5.3 Trigger output
Specifications
Figure 5.2 - Trigger output block diagram.
In the default software configuration, the output swing is 1.6 V (±0.8 V) when unloaded and 0.8 V (±0.4
V) when terminated on 50 Ω. The rise and fall times are 2.5 ns typical. The offset can be adjusted by
software control in the range [–2.5 V to +2.5 V] unloaded, or [-1.25 V to +1.25 V] into 50 Ω. The
maximum output current capability is ±15 mA. As the output is retro-terminated, it is possible to drive a
50 Ω line un-terminated (HiZ) without loss of performance.
For a TTL compatible signal, set the offset to 1.0 V and the swing at destination will be +0.2 to +1.8 V.
For an ECL compatible signal, terminated on 50 Ω to –1.2 V, set the offset to –1.2 V and the output will
be in the range [–0.8 to –1.6 V]).
Alternatively, to reduce the current drawn from the ADC card, the terminations shown here can be
used:
Figure 5.3 - Suggested trigger signal terminations.
The external trigger output functionality is implemented in the hardware. No trigger out signal occurs
for software-generated or digital triggers.
52 U5309A User's Manual