The startup time is calculated by the following formula as described in Startup Time (1) . The temperature characteristics of the startup time are determined by the temperature characteristics of L1, RL and |-R|.

Tstr: Startup time
k: Proportionality constant
L₁: Equivalent motional inductance of crystal unit
|-R|: Negative resistance of the circuit (absolute value)
R_L: load resonance resistance of crystal unit

1. Temperature characteristics of "L₁: Equivalent motional inductance of crystal unit"
In operating temperature range specified in the specifications, L₁ is almost the same.

2. Temperature characteristics in "R_L: load resonance resistance in crystal unit"
In operable temperature range specified in the specifications, R_L is almost the same.

3. "|-R|: Temperature characteristics of circuit negative resistance (RMS Value)"
As described in Negative resistance (4) , "The tendency generally decreases linearly from low temperature to high temperature."

This means that the higher the temperature, the greater the startup time.