High-precision temperature-controlled crystal oscillator

Abstract

The invention discloses a high-precision temperature-controlled crystal oscillator, the circuit of the oscillator comprises a temperature-controlled circuit and a main oscillation part circuit, wherein the temperature-controlled circuit comprises a medium value-B thermistance RT1 of a negative temperature coefficient, two operational amplifiers IC1A and IC1B and two plug-and-play (PNP) triodes Q1 and Q2. Considering the advantages and disadvantages of two parties in the traditional technology, a double-operation-amplifier and double-monitoring-point temperature-controlled circuit is originally created, so a precise temperature-controlled effect of three operation amplifiers can be realized; the simultaneous monitoring of thermal parameters and current parameters is utilized, so the heating control is more precise and more correct; and moreover, the production cost is reduced, and the thermistance is accessed to the circuit in a grounding way simultaneously, so the thermistance is convenient to debug, the mass production can be realized, and stronger competitive strength can be realized compared with the foreign similar products.

Description

[0001] technical field [0002] The invention relates to the technical field of electronics and circuits, in particular to a circuit of a temperature-controlled crystal oscillator, including a sampling circuit and a main oscillator circuit. Background technique [0003] The constant temperature crystal oscillator is realized by constant temperature and precise temperature control of the crystal. As a precise time-frequency signal source, it is widely used in electronic instruments such as global positioning systems, communications, metering, telemetry and remote control, spectrum and network analyzers. It is the core device of all electronic equipment and is known as the "heart". [0004] At present, the main form of the domestic temperature control circuit is the single-variable control type with a single op-amp, and the heating tube generally uses a field effect tube. This kind of heating and temperature control circuit is too simple because it only has a single set of va...

AI Technical Summary

Problems solved by technology

This kind of heating and temperature control circuit is too simple because it only has a single set of variable parameters, and the temperature control is not very precise, which leads to large temperature fluctuations in the constant temperature tank of the product, which in turn affects the performance of the entire product; while some foreign manufacturers use Three operational amplifier temperature control circuit, this kind of heating circuit is complex, high cost, cumbersome debugging, has high requirements for technical personnel, and increases the material cost of the product at the same time, so the competitive advantage is not obvious, it is difficult to popularize and apply

Since the induction effect of the temperature sensor is relatively slow, if the temperature induction is used to control the heating tube to work, the effect is not ideal.

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