Design Of TCXO Chip

From the beginning of electronic technical appearance, there conies out many different ways to get frequency source. Because of the good frequency stability, quartz crystal oscillator is mainly used as the precise frequency source. But with the quick progressing of portable electronic products (eg: communication equipment), the requirement of the frequency source is more and more precise. The crystal has an intrinsic temperature characteristic that the oscillator frequency will be deviate from temperature as a 3^rd order curve. This characteristic influences the usable temperature range of crystal oscillator. There are two ways to get stable frequency source in a wide range, which are temperature control and temperature compensation.Temperature control is a way that the sensitive components of the oscillator are placed in a temperature stable chamber. In the case of a crystal oscillator, the crystal is placed in a thermal oven that is held at a constant temperature. By this way, oscillators can escape from the influence of temperature, and the oscillators can get extremely stable precise frequency. However, because of the significant size and large current draw, it cannot fit to the application of portable electronic products.Temperature compensation is the other way to get the stable precise frequency source. At first, the temperature signal is measured through the temperature sensor, and then the voltage, which will be imposed into the voltage controlled crystal...