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Model T940 User Manual
Publication No. 980938 Rev. K
DRM Timing Characteristics J-2
Astronics Test Systems
External AUX Output T
i
ming Adjustments
LVTTL: timing reference
ECL: 0 ns (same as LVTTL)
Programmable: +8 ns (slower)
422/485: TBD
TRG Input Timing Adjustments
TTLTRG Bus: timing reference (based on the leading edge*)
ECLTRG Bus: +5 ns (slower)
Note: The TTLTRG Bus open-collector recovery time is 17 ns min. and
increases ~4 ns for each DRM installed. Other VXI modules installed in the
same chassis may further aggravate the recovery time.
*
The leading edge for the TTLTRG Bus is a falling edge.
TRG Output T
i
ming Adjustments
TTLTRG Bus: timing reference (to the leading edge)
ECLTRG Bus: -1 ns (faster)
AUX Input to TRG
AUX LVTTL to TTLTRG Bus: 16 ns
TRG Input to AUX Output
TTLTRG to AUX LVTTL: 15 ns (LE)
DRS Timing Adjustments
Independent: timing reference
Linked: +1 ns
VXI Local Bus: ~1.5 ns/DRM
TTLTRG Bus: ~1 ns/DRM
ECLTRG Bus: ~1 ns/DRM
External T0CLK to T0CLK In (at min. delay setting)
Independent:
AUX LVTTL to LVTTL: 86 ns (500 MHz master clock)
AUX LVTTL to LVTTL: 140 ns (250 MHz master clock)