SNAS835A September 2022 – February 2025 LMK5B33414
PRODUCTION DATA
The APLL loop filter components can be programmed to optimize the APLL LBW depending on the phase noise of the XO input. The BAW APLL supports a programmable LBW from 100Hz to 10kHz (typical range) and the conventional LC APLL supports a programmable LBW from 100kHz to 1MHz (typical range). Figure 8-24 shows the APLL loop filter structure between the PFD/charge pump output and VCO control input.
The BAW APLL is configured with a narrow LBW by default in TICSPRO and the ROM pages. As a result, the low jitter VCBO dominates the clock output phase noise in the carrier offset range from 8kHz to around 400kHz.
Using the default APLL loop filter settings listed in Table 8-3, the LBW for each APLL is summarized in Table 8-4.
COMPONENT | LOCATION | TYPE | DEFAULT VALUES FOR APLL1 | DEFAULT VALUES FOR APLL2 | DEFAULT VALUES FOR APLL3 |
---|---|---|---|---|---|
Charge pump | Internal | Programmable | 6.4mA | 3.4mA | 2.0mA |
C1 | Internal | Fixed | 100pF | 100pF | 100pF |
C2 | External(1) | Fixed | 100nF | 100nF | 470nF |
C3 | Internal | Programmable | 70pF | 70pF | 70pF |
C4 | Internal | Programmable | 70pF | 70pF | 70pF |
R2 | Internal | Programmable | 0.222kΩ | 0.183kΩ | 0.301kΩ |
R3 | Internal | Programmable | 0.657kΩ | 0.657kΩ | 5.5kΩ |
R4 | Internal | Programmable | 0.657kΩ | 0.657kΩ | 5.5kΩ |
APLL | VCO RANGE [MHz] | LBW [kHz](1) |
---|---|---|
1 | 4800 to 5350 | 282.5 to 291.8 |
2 | 5600 to 5950 | 152.8 to 137.8 |
3 | 2500 | 4.9 |