MODEL 744 QUAD LINEAR GATE FAN-IN/OUT

FEATURES
Four Independent Fast Analog Switches
Linear or Logic Fan-In of Four and Fan-Out of Six per Channel
Wideband - DC to 250 MHz
Ideal for Fast Analog Multiplexing or Demultiplexing
Fully Bipolar Operation to +/-2.5 Volts
Reliable - Both Inputs and Outputs are protected

DESCRIPTION

The Model 744 is a four channel unity gain linear gate with fan-in/fan-out packaged in a single width NIM module. The linear gate function allows clipping of bipolar signals producing unipolar pulses for subsequent analog to digital conversion. Also tasks such as analog multi- plexing from N lines to one line are easy to implement, as well as, analog demultiplexing from one line to N lines. Four linear inputs provide summing of linear levels or pulses. Both in- verted and noninverted output levels are produced simultaneously allowing very complex analog triggers to be fast and easy to develop. Direct coupling of all inputs and outputs eliminates the baseline shifts due to rate or duty cycle affects, while also making the device useful for performing logic functions.

 INPUT CHARACTERISTICS
 Summing Inputs   Four LEMO connectors per channel, bipolar input accepts positive or
       negative voltages; impedance 50 ohms +/-2% direct coupled, input
       reflections less than +/-4% for 1 nsec risetime.
 Protection    Protected with clamping diodes, no damage will occur from transients
       of +/-100 Volts (+/-2 amps) for 1 uSec or less duration.
 Gate Input    One LEMO connector per channel, 50 ohm impedance direct coupled;
       the analog switch is normally closed with no gate applied, and will oper
       with a negative NIM level of -500 mV or greater. Gate opening and
       closing times are less than 2 nsec. Accepts normal or complemented
       NIM levels or pulses.
 Off Isolation   Better than 60 db for DC to 100 MHz inputs.
 Gate Feedthrough   Less than 1 pC, or less than +/-40 pVolt second glitch.
 OUTPUT CHARACTERISTICS
 General     Six bridged LEMO output connectors per channel. Four non-inverted
       outputs and two inverted outputs low impedance voltage source output
       stage.
 Protection   : Outputs can be continuously shorted to ground without damage.
 Output Voltage Swing: Bipolar outputs deliver over +/-2 Volts across four 50 ohm loads.

 DC Offset    A front panel 15-turn potentiometer provides +/-500 mVolt adjustment,
       the front panel test point allows easy monitoring of the DC offset.
 GENERAL PERFORMANCE
 Gain      Fixed gain of 1.0 +/-2% both inverted and non-inverted.
 Stability    Better than +/-100 uVolt/'C from DC to 1 MHz, and +/-.05%/'C above
       1 MHz.
 Linearity    +/-0.4%, outputs to +/-2 Volts across two 50 ohm loads or +/-1.5 Volts
       across four 50 ohm loads.
 Bandwidth    DC to 250 MHz, 3 db point 1 Volt peak to peak.
 Wideband Noise   Less than 500 uvolts RMS, referred to the input, <30 nV/Hz^.5).
 Risetime     Typically 1.4 nSec, for a 1 Volt output excursion.
 Crosstalk    Greater than 60 db, DC to 100 MHz.
 Power Supply    +6V @ 425 mA  +12V @ 170 mA  +24V @ 85 mA
 Requirements    -6V @ 425 mA  -12V @ 170 mA  -24V @ 85 mA