Oscillator Circuits

Rudolf F. Graf

• Publisher: Newnes
• Year: 1996
• ISBN:
  9780080513416
• Topic: Design
• Subtopic: Industrial Design

This series of circuits provides designers with a quick source for oscillator circuits. Why waste time paging through huge encyclopedias when you can choose the topic you need and select any of the specialized circuits sorted by application?This book in the series has 250-300 practical, ready-to-use circuit designs, with schematics and brief explanations of circuit operation. The original source for each circuit is listed in an appendix, making it easy to obtain additional information.

• Ready-to-use circuits
• Grouped by application for easy look-up
• Circuit source listings

1

Audio Oscillators

The sources of the following circuits are contained in the Sources section, which begins on page 173. The figure number contained in the box of each circuit correlates to the source entry in the Sources section.

Wen-Bridge Sine-Wave Oscillator

Phase-Shift Oscillator

Wien-Bridge Oscillator

Code-Practice Oscillator

Tone Encoder

Feedback Oscillator

Wien-Bridge Oscillator

Wen-Bridge Oscillator

Phase-Shift Oscillator

800-Hz Oscillator

Wien-Bridge Oscillator

Wien-Bridge Sine-Wave Oscillator

Sine-Wave Oscillator

Easily Tuned Sine-/Square-Wave Oscillator

Very-Low-Frequency Generator

Audio Oscillator

Electronic Bagpipe

Simple Audio Sine-Wave Generator

Low-Cost Wien-Bridge Oscillator

Modified UJT Relaxation Oscillator

A 555 RC Audio Oscillator

Wien-Bridge Oscillator Uses CMOS Chip

Adjustable Sine-Wave Audio Oscillator

One-IC Audio Generator

Simple Two-Tone Generator

Low-Distortion Thermally Stabilized Wien-Bridge Oscillator

Audio Oscillator

Audio Generator

Single-Supply Wien-Bridge Oscillator

Super-Low-Distortion Variable Sine-Wave Oscillator

1-kHz Oscillator

Inexpensive Oscillator is Temperature Stable

Code-Practice Oscillator

Audio Oscillator

WIEN-BRIDGE SINE-WAVE OSCILLATOR

The 2N5457 JFET, as a voltage variable resistor in the amplifier feedback loop, produces a low distortion, constant amplitude sine wave getting the amplifier loop gain just right. The LM103 zener diode provides the voltage reference for the peak sine wave amplitude.

Fig. 1-1 NATIONAL SEMICONDUCTOR

PHASE-SHIFT OSCILLATOR

Circuit uses a simple RC network to produce an exceptionally shrill tone from a miniature speaker. With the parts values shown, the circuit oscillates at a frequency of 3.6 kHz and drives a miniature 2½Π speaker at ear-piercing volume. The output waveform is a square wave with a width of 150 µs, sloping rise and fall times, and a peak-to-peak amplitude of 4.2 volts (when powered by 9 volts). Current drain of the oscillator is 90 mA at 9 volts, and total power dissipation at this voltage is 0.81 watt, which is well below the 1.25 watts the 14-pin version will absorb (at room temperature) before shutting down.

Fig. 1-2 NATIONAL SEMICONDUCTOR

WIEN-BRIDGE OSCILLATOR

Fig. 1-3 FAIRCHILD CAMERA

Field effect transistor, Q1, operates in the linear resistive region to provide automatic gain control. Because the attenuation of the RC network is one-third at the zero phase-shift oscillation frequency, the amplifier gain determined by resistor R2 and equivalent resistor R1 must be just equal to three to make up the unity-gain positive-feedback requirement needed for stable oscillation. Resistors R3 and R4 are set to approximately 1000 ohms less than the required R1 resistance. The FET dynamically provides the trimming resistance needed to make R1 one-half of the resistance of R2. The...

Table of contents

• Cover image
• Title page
• Table of Contents
• Copyright
• Other Books in this Series
• Introduction
• Chapter 1: Audio Oscillators
• Chapter 2: Crystal Oscillators
• Chapter 3: Function Generators
• Chapter 4: Miscellaneous Oscillators
• Chapter 5: Multivibrators and Square-Wave Oscillators
• Chapter 6: RF Oscillators
• Chapter 7: Sirens, Warblers and Wailers
• Chapter 8: Voltage-Controlled Oscillators
• Sources
• Index