A. Specifications
Inputs
INPUT - Accepts positive or negative signals from an associated preamplifier; ampli-
tude
±
10 V divided by the selected gain,
±
12 V maximum; rise time: less than the se-
lected flat top time setting; decay time constant: 40
µ
s to 1.7 ms for RC Preamp mode,
infinity for TRP mode; Z
in
varies with Coarse Gain and polarity setting from 500 to
2k.
GATE IN - Accepts a positive logic pulse or dc level; high amplitude
≥
+2.5 V, Low
amplitude
≤
+400 mV, 0 to +7 V maximum; dc coupled; open input allows PHA opera-
tion; Loading is 1k to +5 V with Coincidence selected and 1k to 0 V for Anticoinci-
dence; width
≥
50 ns; In COINC (ANTIcoincidence) mode a positive (negative) logic
pulse or dc level during the rise time and flat top of the trapezoidal waveform will en-
able the conversion in process; if the GATE IN is low (high) during this time the im-
pending conversion will be disabled; the reconstructed trapezoidal waveform may be
viewed on the MONITOR output.
INHIBIT - Accepts a standard TTL logic signal; functionality is dependent on which
Inhibit Mode is selected. NORM selected: resets and inhibits the pileup rejector and
extends the Dead Time signal for the duration of the INH signal; RESET preamp se-
lected: inhibits the 9660 during the preamplifier reset cycle, the leading edge of the
INH signal resets the pileup rejector and initiates the 9660 to automatically disable
pulse processing and extend the system dead time for the duration of the resultant
overload event. The total inhibit time is the OR” of the external INH signal and the
9660 reset disable time, whichever is longer. Positive true or negative true signal po-
larities, user selectable; minimum pulse width is 1
µ
s; loading 4.7K; logic high
≥
+3.6
V, logic low
≤
+1 V; 0 to +12 V maximum; rear panel BNC connector.
ICB - Provides for connection to the Instrument Control Bus. Computer control of the
Model 9660 is through this bidirectional interface; rear panel 20-pin ribbon cable con-
nector.
Outputs
MONITOR - Provides viewing of sampled data, reconstructed in time; digitally fil-
tered Trapezoidal/Triangular pulse; amplitude linear to +8 V, 8 V max; Z
out
≈
50
Ω
;
short circuit protected; front panel BNC connector; provided as a user aid to assist
with setup.
Appendix A - Specifications
56
Model 9660-9660A ICB Digital Signal Processor