MODEL 776 PHOTOMULTIPLIER PREAMPLIFIER

FEATURES
* Ideal for many types of detectors
* High packaging density - 16 channels/single width NIM
* Wideband - Direct Coupled to 275 MHz
* Low noise performance
* Excellent stability
* LOW cost

The model 776 is a 16 channel preamplifier packaged in a single width NIM module. Each channel has a non-inverting voltage gain of 10 and operates from DC to over 275 MHz, with two 50 ohm outputs per amplifier. It is designed for use with detectors having negatively going output pulses. Both the input stage and output stages are protected for reliable operation.

 INPUT CHARACTERISTICS

 Impedance     : 50 ohms +2%, reflections less than +4% for 2 nsec input
        risetimes.

 Protection     : No damage to the input stage will result from transients
        of +/-100 Volts (+2 amps) for 1 usec or less duration.

 Wideband Noise    : Less than 25 uVolts RMS, referred to the input.

 Input Offset Voltage  : Less than +/-300 uVolts.

 overdrive Recovery Time : Less than 15 nSec for a 1 Volt input.

 OUTPUT CHARACTERISTICS

 Type      : Two bridged; Voltage source output stage, each output
        capable of driving a 50 ohm load.

 Output Voltage Swing  : Greater than -3 Volts across 25 ohm load. +.5 Volts
        across 50 ohm load. +.25 Volts across 25 ohm load.

 Output Protection   : Outputs can be continuously shorted to ground without
        suffering damage.

 Offset Voltage    : Less than +4 mVolts, an internal 15-turn potentiometer
        allows control of +/-10 mvolt to compensate for offsets
        due to ground drops or source impedances other than
        50 ohms. All channels vary simultaneously.

 GENERAL CHARACTERISTICS

 Gain       10 +2%, non-inverting

 Stability      +/-5.0 uVolt/'C, referred to the input.

 Linearity      +/-.l% to -3 Volts, DC to 100 MHz

 Bandwidth      DC to 275 MHz minimum, 3 db point.

 Risetime      Less than 1.3 nsec.

 Crosstalk      Greater than 60 db, DC to 100 MHz.

 Input/Output Delay    Typically 3.0 nsec.

 Power Supply Requirements: +6 V @ 320 mA  +12 V @ 150 mA
        -6 V @ 320 mA  -12 V @ 150 mA