SPRSP92D February 2023 – December 2024 AM69 , AM69A
PRODUCTION DATA
Refer to the PDF data sheet for device specific package drawings
Figure 6-28 shows the recommended crystal circuit. All discrete components used to implement the oscillator circuit should be placed as close as possible to the OSC1_XI and OSC1_XO pins.
The crystal must be in the fundamental mode of operation and parallel resonant. Table 6-23 summarizes the required electrical constraints.
PARAMETER | MIN | TYP | MAX | UNIT | |||
---|---|---|---|---|---|---|---|
Fxtal | Crystal Parallel Resonance Frequency | 19.2 | 27 | MHz | |||
Fxtal | Crystal Frequency Stability and Tolerance | Ethernet RGMII and RMII not used | ±100 | ppm | |||
Ethernet RGMII and RMII using derived clock | ±50 | ||||||
CL1+PCBXI | Capacitance of CL1 + CPCBXI | 12 | 24 | pF | |||
CL2+PCBXO | Capacitance of CL2 + CPCBXO | 12 | 24 | pF | |||
CL | Crystal Load Capacitance | 6 | 12 | pF | |||
Cshunt | Crystal Circuit Shunt Capacitance | 19.2MHz ≤ Fxtal ≤ 20MHz | ESRxtal ≤ 30 Ω | 7 | pF | ||
30 Ω ≤ ESRxtal ≤ 80 Ω | 5 | pF | |||||
80 Ω ≤ ESRxtal ≤ 100 Ω | 3 | pF | |||||
20MHz ≤ Fxtal ≤ 24.576MHz | ESRxtal ≤ 30 Ω | 7 | pF | ||||
30 Ω ≤ ESRxtal ≤ 60 Ω | 5 | pF | |||||
60 Ω ≤ ESRxtal ≤ 80 Ω | 3 | pF | |||||
Not Supported: 80 Ω ≤ ESRxtal | – | ||||||
24.576MHz ≤ Fxtal ≤ 25MHz | ESRxtal ≤ 30 Ω | 7 | pF | ||||
30 Ω ≤ ESRxtal ≤ 50 Ω | 5 | pF | |||||
50 Ω ≤ ESRxtal ≤ 80 Ω | 3 | pF | |||||
Not Supported: 80 Ω ≤ ESRxtal | – | ||||||
25MHz ≤ Fxtal ≤ 27MHz | ESRxtal ≤ 30 Ω | 7 | pF | ||||
30 Ω ≤ ESRxtal ≤ 50 Ω | 5 | pF | |||||
Not Supported: 50 Ω ≤ ESRxtal | – | ||||||
ESRxtal | Crystal Effective Series Resistance | 100 | Ω |
When selecting a crystal, the system design must consider the temperature and aging characteristics of a based on the worst case environment and expected life expectancy of the system.
Table 6-24 details the switching characteristics of the oscillator and the requirements of the input clock.
PARAMETER | PACKAGE | MIN | TYP | MAX | UNIT | ||
---|---|---|---|---|---|---|---|
CXI | XI Capacitance | ALY | 1.989 | pF | |||
CXO | XO Capacitance | ALY | 1.971 | pF | |||
CXIXO | XI to XO Mutual Capacitance | ALY | 0.01 | pF | |||
ts | Start-up Time | 9.5(1) | ms | ||||
PARAMETER | PACKAGE | MIN | TYP | MAX | UNIT | ||
CXI | XI Capacitance | ALY | 1.989 | pF | |||
AND | 2.548 | pF | |||||
CXO | XO Capacitance | ALY | 1.971 | pF | |||
AND | 2.878 | pF | |||||
CXIXO | XI to XO Mutual Capacitance | ALY | 0.01 | pF | |||
AND | 0.01 | pF | |||||
ts | Start-up Time | 9.5(1) | ms |