（TCXO2520及VC-TCXO2520尺寸脚位说明）
Temperature Compensated Crystal Oscillators (TCXO)
TCXO is the Crystal Oscillator with good temperature characteristics of Crystal unit and opposite temperature characteristics circuit (temperature compensation circuit) across a wide temperature range.
标准频率：19.2MHz/26MHz/38.4MHz
外部尺寸 ：2.5 ×2.0 × 0.8mm
应用领域：GPS, RF, 无线通信设备LTE, WiMAX, Wi-Fi, W-LAN, IoT等
输出波形：削峰正弦波（ Clipped Sine Wave）
电源电压 ：1.8 V Typ./ 2.8 V Typ./ 3.0 V Typ./ 3.3 V Typ.
额定电压范围：1.8V ±0.1V / 2.8V ±5% / 3.0V ±5% / 3.3V ±5%
频率电源电压特征：VCC ± 5%条件下：±0.1 × 10-6 Max.
频率负载变动特征：10kΩ // 10pF ±10%条件下：±0.1 × 10-6 Max.
频率温度特征
±0.5 × 10-6 Max. (-40°C to +85°C)
±2.0 × 10-6 Max. (-40°C to +85°C)
工作温度范围：-40°C to +85°C
频率温度特征： ±0.5 × 10-6 Max. / G: -40°C to +85°C
特性：低相位噪音
频率老化：±0.5 × 10-6 Max.
功耗：1.5 mA Max.~ 2.0 mA Max.
输入电阻：500 kΩ Min.
占空比：45% to 55%
振荡启动时间：1.0 ms Max.
温补晶振TCXO测试电路如下：
压控温补晶振VC-TCXO测试电路如下：
备注：
1、请保持“N.C.”引脚开路状态。
2、“N.C.” 引脚不能用作接地引脚。
3、为了维持稳定运行，在接近晶体产品的电源输入端处（在VCC-GND 之间）添加一个0.01~0.1uF的去耦电容。
What is a voltage controlled temperature compensated crystal oscillator?
Temperature Compensated Crystal Oscillators (TCXOs) deliver excellent temperature characteristics combined with low power consumption and fast warmup. Voltage Controlled Temperature Compensated Crystal Oscillators (VC-TCXOs) combine the same excellent temperature characteristics, low power consumption and fast warmup with a voltage control function to allow precise tuning of the output frequency after PCB assembly.
Voltage control can also be used during operational life, to compensate for any effects of aging as well as offering the ability to pull back to nominal frequency where there is a change of circuit conditions. TCXOs and VC-TCXOs are used where the stability of a standard Crystal Clock Oscillator is insufficient.
