Cmu_Hfxosteadystatectrl - Hfxo Steady State Control - Silicon Laboratories EFR32xG14 Wireless Gecko Reference Manual

11.5.7 CMU_HFXOSTEADYSTATECTRL - HFXO Steady State Control

Offset
0x030
Reset
Access
Name
Bit Name
31:28 REGISHUPPER
Set to steady state value of REGISH + 3.
27 Reserved
26 PEAKDETEN
Direct control allowed when PEAKDETSHUNTOPTMODE=MANUAL and HFXO is ready.
25:24 REGSELILOW
Steady state used during HFXO FSM. Direct control allowed when PEAKDETSHUNTOPTMODE=MANUAL and HFXO is
ready.
23:20 Reserved
19:11 CTUNE
This CTUNE value is applied during the steady state phase of the HFXO (as well as during the peak detection and shunt
current optimization algorithms). Capacitance on HFXTAL_N and HFXTAL_P (pF) = Ctune = Cpar + CTUNE<8:0> X 40fF.
Max Ctune 25pF (CLmax ~12.5pF). CL(DNLmax)=50fF ~ 0.6ppm (12.5ppm/pF).
10:7 REGISH
This REGISH value is applied during the steady state phase of the HFXO. Direct control allowed when PEAKDETSHUN-
TOPTMODE=MANUAL and HFXO is ready. Ish = 120uA + REGISH X 120uA.
6:0 IBTRIMXOCORE
This IBTRIMXOCORE value is applied during the steady state phase of the HFXO. It is also used as the initial value during
the peak detection algorithm. Direct control allowed when PEAKDETSHUNTOPTMODE=MANUAL and HFXO is ready.
Current (uA) = IBTRIMXOCORE x 40uA. Bits 6 and 5 may only be high in the crystal oscillator startup phase..
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Reset Access Description
0xA RW Set Regulator Output Current Level (shunt Regulator). Ish = 120uA
+ REGISHUPPER X 120uA
To ensure compatibility with future devices, always write bits to 0. More information in
tions
0 RW Enables Oscillator Peak Detectors
0x3 RW Controls Regulator Minimum Shunt Current Detection Relative to
Nominal
To ensure compatibility with future devices, always write bits to 0. More information in
tions
0x168 RW Sets Oscillator Tuning Capacitance
0xA RW Sets the Steady State Regulator Output Current Level (shunt Reg-
ulator)
0x07 RW Sets the Steady State Oscillator Core Bias Current.
Bit Position
Reference Manual
CMU - Clock Management Unit
1.2 Conven-
1.2 Conven-
Rev. 1.1 | 318