Pulse circuits ( 12 ) :

Pulse circuits are circuits which generate a pulse with predeterminedpulse width at constant predetermined rate or at on-need basis.
 

• 555 makes handy voltage-to-time converter - This circuit is a simple, low-cost voltage-to-time converter using the ubiquitous 555 timer chip.   
• Circuit forms constant-current SCR - Resembling an SCR, this circuit provides a constant current of controlled pulse width and amplitude to a load.   
• CMOS buffer delivers precise current pulses - this circuit delivers stable, fast-settling reference-current pulses   
• Delay line aids in one-shot simulations - Many designers use small pulse generators to delay signals, open timing windows, drive sample/hold circuits, and other functions. Though the hardware implementation of these generators does not pose any problems, the lack of dedicated circuitry sometimes puzzles the Spice simulation of the system.   
• High-speed pulse generator has programmable levels - This circuit can create fast rise time pulses whose high and low levels are programmable. Signal rise times in nanoseconds range. Pulse rate can be controlled with external circuit.   
• Micropower pulse generator - produces clean 2mS logic pulses at rate of one per second while drawing only 1 microamp from a 9 volt battery, uses 2 transistor acting as programmable unijunction transistor, pdf file   
• One-shot remembers input-pulse width   
• Pulse discriminator excises narrow pulses - circuit deletes narrow pulses from fixed-frequency PWM waveforms   
• Pulse-width trimmer outdoes one-shots - trims the trailing portion of a large-width input pulse to a size as narrow as 10 nsec irrespective of the input-pulse width, circuit doesn't require a capacitor to generate the timing pulse   
• Repeating one-shot yields clean, stable pulses   
• Time Domain Reflectometer (TDR) - produces very sharp pulses in range of 10 ns to 5 us   
• �C squares input signal - converting a random-width pulse to a signal with the same frequency but with a 50% duty cycle isn't easy but a small microcontroller can do it   

 back to : Links >> Electronic Circuits >> Oscillators