The instrument provides eight decade ranges of pulse periods/frequencies (50 ns to 5 s/20 MHz to 0.2 Hz) and eight decade ranges of pulse duration (25 ns to 2.5 s). Provisions are made for the application of external signals, if desired, to control the pulse repetition frequency (prf) ; to gate the output; and to modulate the amplitude, period, and duration of the pulses.
Both positive and negative ground-based pulses of up to 10 V and offsets to + 1 V are produced simultaneously, and their amplitude and offsets can be independently set with front-panel controls. Also on the front panel are calibrated controls for adjusting pulse amplitude, pulse period/frequency, and pulse duration. Control is also provided for output impedance, single pulsing, input threshold for external prf sources, and for producing square waves.
Many features of the GR 1340 have been incorporated to aid in the testing of integrated circuits. Its 20-MHz operation, adjustable offset, square-wave outout, and ability to operate at the standard 5-V logic level with a 50-ohm source impedance are especially valuable in integrated-circuit testing. The ability to linearly modulate the pulse amplitude, duration, and period makes the 1340 useful in automatic and semiautomatic measurements.. PULSE PERIOD (PRF) Internally Generated: 50 ns to 5 s (20 MHz to 0.2 Hz) in 8 decade ranges. Single-pulse push button on panel. Externally Controlled: 1 Hz to 20 MHz; triggers on any waveform of >3 V pk-pk. Input re- sistance approx 100 k ohm. Output pulse is started by negative-going transition. Period control acts as input trigger-level control in external mode.
OUTPUT-PULSE CHARACTERISTICS Duration: 25 ns to 2.5 s in 8 decade ranges, or square wave. Rise and Fall Times: 5 ns -2 ns at 5 V, 50 ohm load, and 50 ohm source resistance. Amplitude: Positive and negative ground-based pulses available simultaneously with indepen- dent amplitude and offset control. Source current continuously adjustable to at least 0.2 A (i.e., across 50 ohm load, 10 V from high source resistance or 5 V from 50 ohm source). Offset: Continuously adjustable source current from -20 to +20 mA. Source Resistance: 50 ohm, or high (approx 1 kohm) for 5O-ohm loads. Distortion: Preshoot, overshoot, ringing, etc, <0.5 V (5% of max output). Duty Ratio: Duty ratios of over 70% can be obtained on all ranges except decreasing to approx 50% at 50 ns period in 50 to 500 ns range. SYNCHRONIZING PULSE Waveform: Square wave. Negative transition precedes start of output pulse b y approx 35 ns; positive transition can be used for half-period pretriggering. Amplitude: 2.5V pk-pk positiive square wave behind 500-ohm source impedance. MODULATION AND GATING Modulation: Period and duration are linearly controllable by an external voltage between -0.5 and -5.0 V. Amplitude of the positive- pulse output is linearly controllable by an external voltage of 0 to +5 V, the negative- pulse output by 0 to -5 V. Period and duration are modulatable over the decade range set by range switches; amplitude can be modulated over its full range. Amplitude modulation can be used for noncoherent gating of output pulse. Gating: An impedance of <=600 ohm to ground inhibits output; +4 to +8 V allows normal output; 1340's can be used to gate 1340's. GENERAL Power Required: 100 to 125VAC or 200 to 250VAC, 50 to 400 Hz, 30 W.