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LINEAR SAWTOOTH GENERATOR
TRIGGERED_SAWTOOTH_GENERATOR Reprinted Url Of This Article: http://www.seekic.com/circuit_diagram/Basic_Circuit/TRIGGERED_SWEEP.html
Sawtooth Generator For Sweep Generators
OP_AMP_SAWTOOTH_GENERATOR
Triggered Sweep / Timebase Generator

Bridged Differential Amplifier

A symmetrical differential amplifier, with common-mode servo controlling bias voltage. (-Out + +Out) / 2 should remain constant. Addition of a buffer (e.g., emitter follower) to each side should give a balanced (bridgable) power amplifier, taking care to allow feedback to adjust AC balance as well as quiescent operating point. Half the time, I can convince myself this circuit will be stable...

Oscilloscope-Triggered Sweep using 555 IC

We can use the 555 timer to hold the cost down of adding a triggered sweep to an economy oscilloscope. The timer is triggered by the circuit’s input op amp, adjusting its flip-flop and cutting off its discharge transistor so that capacitor C can charge. The flip-flop resets and the transistor conducts when capacitor voltage reaches the timer’s control voltage (0.33Vcc), discharging the capacitor. By substituting a constant-current source for the frequency adjust resistor (R), we can achieve greater linearity. Here’s the circuit diagram:

Combination of 555 timer and standard opamp minimizes cost of adding triggered sweep to oscilloscope not having this feature. Timer is triggered by applying vertical-amplifier signal through opamp, initiating charging of sweep capacitor C. When capacitor voltage reaches control voltage of timer (0.33 VCC), flip-flop in timer resets and capacitor discharges to form retrace of sweep.- Signetics Analog Data Manual, Signetics, Sunnyvale, CA, 1977, p 726.

Developed for use with general-purpose CR0 in troubleshooting digital circuits, to provide one horizontal sweep of cathoderay beam each time circuit is triggered by input signal pulse. Noninverting input of 741 opamp is connected to vertical amplifier of CRO,and inverting input is used to control trigger level. When input signal rises above trigger level, output of opamp swings to -V and makes output of 555 timer go high, allowing output capacitor to charge at constant cuirent through transistor in series with resistor. Resultis nearly perfect ramp voltage. All diodes are 1N914. an is any PNP switching transiston-W. J. Prudhomme, Trigger Your Oscilloscope, Kilobaud, Aug. 1977, p 34-38.

LINEAR SAWTOOTH GENERATOR

http://www.tradeofic.com/Circuit/352-LINEAR_SAWTOOTH_GENERATOR.html

NE555 2N3906
The 2N3906 transistor is used as a constant-current source, to assure that the 555-based sawLooth generator generates a linear ramp waveform.

TRIGGERED_SAWTOOTH_GENERATOR

Reprinted Url Of This Article:
http://www.seekic.com/circuit_diagram/Basic_Circuit/TRIGGERED_SWEEP.html

Two 2N3904 transistors and a 555 form a triggered sawtooth generator. A sawtooth or other rising voltage input provides a pulse output when the trigger point is reached.

Sawtooth Generator For Sweep Generators

http://www.next.gr/rf/receivers/sawtooth-generator-for-sweep-generators-l14342.html

This circuit will generate a linear sawtooth between 30 Hz and 3 000 Hz. Ql is a constant-current s
ource that charges CI until the output level at Q3 emitter triggers U1A and U1B, which turns on Q4 and discharges CI. The frequency range can be varied by changing the value of CI. This circuit should be good to several tens of kHz.

OP_AMP_SAWTOOTH_GENERATOR

http://www.seekic.com/circuit_diagram/Signal_Processing/OP_AMP_SAWTOOTH_GENERATOR.html

The sawtooth generator circuit shown is reset at the end of each cycle. The result is a constant peak-to-peak output throughout the circuit's frequency range.The constant-current generator circuit, the voltage-follower circuit, and the comparator circuit produce the waveform. A 555 timer IC (U2) is configured as a one-shot multivibrator that's triggered by the comparator's negative output pulse.

Triggered Sweep / Timebase Generator

http://www.williamson-labs.com/scope-main.htm

Oscilloscopes have several sync modes: internal sync; external sync; line sync and delayed sync. The selection of any of these sync sources sends the signal to the "sync detector." For example: if the internal sync is selected, it sends the input signal, picked-off from the vertical input amplifier, to the "sync detector" which is a fast analog comparator that gets its other comparison input from a front panel mounted control, called the "LEVEL" control. This allows the user to preset the exact voltage level and polarity, at which the scope "triggers" the sweep generator to sweep the beam across the screen once. Every time the signal goes above this preset voltage (except during an active sweep time), a new sweep is started: this is called "Triggered Sweep."