4/8/12 MHz RC Oscillator

The 4/8/12 MHz RC oscillator is calibrated in production. This calibration can be read through the Get CALIB bit command (refer to the Enhanced Embedded Flash Controller (EEFC)) and the frequency can be trimmed by software through the PMC.

Table 1. 4/8/12 RC Oscillator Characteristics
Symbol Parameter Conditions Min. Typ. Max. Unit
ACC4 4 MHz Total Accuracy(2) 4 MHz output selected (see Note 1) -35 46 %
4 MHz output selected at 25°C (see Notes 1, 3) -1.2 0.8 %
ACC8 8 MHz Total Accuracy 8 MHz output selected at 25°C (see Notes 1, 3) -1.2 0.8 %
ACC12 12 MHz Total Accuracy 12 MHz output selected at 25°C (see Notes 1, 3) -1.6 0.8 %
Temp dependency (see Note 3) 0.07 0.12 %/°C
tSTART Startup Time 20 µs
Notes:
  1. 1.Frequency range can be configured in the Supply Controller registers.
  2. 2.Not trimmed from factory.
  3. 3.After trimming at 25°C and VDDCORE = 1.2V.