758 OCTAL LOGIC UNIT
The model 758 is a high performance, eight channel, two-input logic unit packaged in a single width NIM module. It performs logical AND, OR, Fan-in and Fan-out functions.
Each channel has two logic inputs, an output width control, and three outputs. A two position switch is common to all eight channels for selecting either the AND/OR logic functions.
Inhibiting of the logic unit 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.
- 150 MHz Rate Capability
- Deadtimeless Updating Operation
- Eight Independent Channels
- 1 nSec Input Coincidence Width (Overlap times of 1nSec or greater will produce outputs.)
- Fast Veto and Bin Gate Inhibiting
- Input to Ouput Delay Less than 8.0 nSec.
- Logic Inputs
- Two LEMO connector inputs per section;
- 50 ohm input impedance, ±2%, direct coupled;
- accepts NIM level logic signals (-500mV or greater).
- Outputs will be produced with inputs of 1 nSec or greater width.
- Inputs are protected against damage from ±100 Volt transients of 1 μSec duration.
- Fast Veto
- One LEMO connector input common to all eight channels;
- accepts normal NIM level pulse(-500 mV), 50 ohm impedance, direct coupled;
- The veto input must precede by 5 nSec, the negative edge of input signal that would ordinarily satisfy the logic conditions;
- Requires a 4 nSec minimum input pulse width.
- Bin Gate
- Rear panel slide switch enables or disables the slow bin gate via the rear connector. Signal levels are in accordance with the TID-20893 standard.
- Inhibits the module within 10 nSec after the bin gate signal is applied.
- Three (3) LEMO connector outputs per section; One negative NIM bridged pair and one complemented output.
- The bridged output delivers -32 mA (-1.6 Volts), into a single 50 ohm load and -16 mA (-800 mV) with both terminated.
- The complement is quiescently -16 mA and goes to 0 mA during output.
- The output rise and fall times are less than 1.5 nSec from 10% to 90% levels.
- Width Control
- One front panel control per channel;
- 15-turn screwdriver adjustment;
- outputs continuously variable from 4 nSec to 150 nSec, updating;
- Output width stability is ±0.15%/oC 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 a 100% duty cycle can be achieved.