SIS Documentation
SIS3800
Scaler/Counter
Page 25 of 39
15 Signal Specification
15.1 Control Signals
The width of the clear and external latch shadow pulse has to be greater or equal 10 ns, an
external inhibit has to be present for the period you desire to disable counting. An internal
delay of some 15 ns has to be taken into account for all external signals.
15.2 Inputs
The SIS3800 is specified for counting rates of 200 MHz for ECL and NIM signals and 100
MHz for the TTL case. Thus the minimum high and low level duration is 2.5 ns (5 ns
respective). Signal deterioration over long cables has to be taken into account.
16 Operating Conditions
16.1 Power Consumption/Voltage requirement
Although the SIS3800 is prepared for a number of VIPA features, it was decided to use an ob
board DC/DC converter to generate the –5 V, which are needed for driver and receiver chips,
to allow for the use of the module in all 6U VME environments. The power consumption is
counting rate dependent, it varies from the idle value of +5 V 3,3 A to +5 V 4,5 A with all
channels counting at 200 MHz(i.e. the power consumption is < 23 W).
16.2 Cooling
Forced air flow is required for the operation of the SIS3800 board.
16.3 Insertion/Removal
Please note, that the VME standard does not support live insertion (hot swap). Hence crate
power has to be turned off for installation and removal of SIS3800 scalers.
The leading pins on the SIS3800 VME64x VME connectors and connected on board circuitry
are designed for hot swap in conjunction with a VME64x backplane (a VME64x backplane
can be recognised by the 5 row VME connectors, while the standard VME backplane has
three row connectors only).
Artisan Technology Group - Quality Instrumentation ... Guaranteed | (888) 88-SOURCE | www.artisantg.com
