Pulser

A pulser, or pulser circuit, is an electronic device that generates pulses—short, transient electrical signals that differ from the steady input level. Pulses can be voltage or current and are used to initiate or synchronize processes in a wide range of systems. Pulsers are designed to produce pulses with precise timing, amplitude, and duration.

Basic pulser architectures rely on switched elements such as transistors, thyratrons, spark gaps, or other fast switches, controlled by a timing network that sets the onset and width of the pulse. They can be single-shot, creating one pulse on command, or repetitively triggered to produce a train of pulses at a chosen rate. Digital and analog techniques shape rise and fall times, pulse width, and amplitude. Some pulsers are designed to drive high-impedance loads, while others deliver short, high-current pulses into matched impedances.

Key specifications include peak voltage or current, pulse width (often nanoseconds to milliseconds), repetition rate, duty cycle, jitter (timing accuracy), rise and fall times, and output impedance. Stability and timing accuracy are critical in synchronization tasks or measurement systems. Noise, overshoot, and pulse distortion are important considerations in design and testing.

Applications span scientific instrumentation and industry. Pulsers trigger pulsed lasers, pump microwave amplifiers, drive radar and lidar transmitters, enable time-domain reflectometry, and facilitate pulsed-power experiments and particle accelerators. They support fast gating in NMR, MRI, and spectroscopy, and are often paired with pulse shaping or arbitrary waveform generators to achieve complex pulse schemes.

Variants include pulse generators, impulse generators, and arbitrary waveform generators with pulsed outputs; modern units may offer programmable pulse shapes, synchronization features, and software interfaces.