* 150 MHZ RATE CAPABILITY
* DEADTIMELESS UPDATING
OPERATION
* FOUR OUTPUTS PER
CHANNEL
* FAST VETO AND BIN
GATE INHIBITING
* LINEAR SUMMED OUTPUT
DESCRIPTION
The model 710 is a high-performance, eight-channel, leading edge
discriminator packaged in a single-width
NIM module. It features independent threshold and
width controls, a fast veto for inhibiting, a prompt linear
summed output, and a versatile output configuration with
four updating outputs per channel.
The 710 has high input sensitivity of -10 mV variable to -1 volt via
a 15-turn front panel control. A front panel test point on
each channel provides a DC voltage equal
to ten times the actual threshold to insure accurate settings.
A unique summed output, common to all eight channels, delivers - 1 mA of current for each activated channel, thus allowing a fast decision to be made on the number of channels simultaneously hit. Up to 16 channels can be "OR'D" directly by cable to other summed outputs providing a versatile scheme to form a trigger.
Inhibiting of the discriminator can be accomplished in two ways. A front panel LEMO input accepts a NIM level pulse for fast simultaneous inhibiting of all eight channels. Secondly, a slow bin gate via the rear panel connector inhibits the module and is enabled or disabled from a rear panel slide switch.
Output durations are continuously variable via a front panel control over the range of 4nSec to 150nSec. The updating design permits deadtimeless operation which is desirable for fast coincidence applications at high rates.
The 710 has four high-impedance current switching outputs per channel. They are configured as one pair of double-amplitude bridged outputs, one normal NIM level and one complemented NIM level. When only one output from the bridged pair is used, a double-amplitude NIM pulse (- 32 mA) is generated for driving long cables. Two normal NIM levels are produced when both of the bridged outputs operate into 50 ohm loads. The output risetimes and falltimes are typically 1 nSec, and their shapes are unaffected by the loading conditions of the other outputs.
INPUT CHARACTERISTICS
General:
One LEMO connector input per
channel; 50 ohms, +/-1%, DC coupled; less than
2% input reflection for a 2.0nSec input risetime. Input
protection clamps at +0.7V and -5.0V and can withstand
+/- 2 amps for 1uSec with no damage to
the input.
Threshold:
-10 mV to 1 volt; one front panel 15 turn screwdriver adustment for
each channel; better than 0.2%/degC stability; front panel test point
provides a DC voltage ten (10) times the actual threshold setting.
Fast Veto:
One LEMO connector input common
to all eight (8) channels; accepts normal NIM level pulse (-500
mV); the veto input must precede the negative
edge of input pulse by 5nSec; 4nSec minimum input
width.
Bin Gate:
Rear panel slide switch enables or disables bin slow
gate in accordance with TID-20893.
OUTPUT CHARACTERISTICS
General:
Four (4) LEMO connector outputs per channel; one set of negative bridged
outputs; one normal NIM level and one complementary output. The bridged
pair deliver a double-amplitude pulse of -32mA
(-1.6 volts into a single 50 ohm load, or -800 mV when both
outputs are 50 ohm terminated). The normal
NIM output delivers -16mA (- 800mV into 50 ohms). The complementary
output is quiescently -16mA (-800 mV into 50 ohms) and delivers 0mA (0
volts into 50 ohms) during output. Output rise-times and falltimes
are less than 1.5nSec from 10% to 90% levels.
Width Control:
One front panel control per channel; 15 turn screwdriver adjustment;
outputs continuously variable from 4nSec to 150nSec.
Output width stability is +/-1.5%/degC of setting.
Updating Operation:
The output pulse will be extended if a new input pulse occurs while
the output is active. This provides deadtimeless operation
and 100% duty cycle can be achieved.
Summed Output:
One LEMO connector output common to all eight (8) channels; -1mA output
pulse (- 50mV into 50 ohms) for each channel fired. Output
duration is equal to the output width setting of the respective channel.
Output risetimes and fall-times are less than 2.5 nSec into
50 ohms. Up to 16 channels can be directly "OR'D"
by cable. -1V of dynamic range.
GENERAL PERFORMANCE
Continuous Repetition Rate:
Greater than 150MHz, with output width set at minimum.
Pulse-Pair Resolution:
Better than 6.5nSec, with output width set at minimum.
Input to Output Delay:
Less than 8nSec.
Multiple Pulsing:
One and only one output pulse regardless of input pulse amplitude or
duration.
Power Supply Requlrements:
-6V @ 420mA +6V @ 415mA
-12V@165mA +12V @ 0mA
-24V@80mA + 24V @ 80mA
115VAC @ 75 mA
NOTE: All currents are wlthin NIM specification limits
allowing a full bin to be operated without overloading.
Operating Temperature:
0degC to 70degC ambient.
Packaging:
Standard single width NIM module in accordance with TID-20893 and section
ND-524.
Quality Control:
Standard 36-hour, cycled burn-in with switched power cycles.