SNAS841 October 2023 LMK04714-Q1
PRODUCTION DATA
The FIN0/FIN1 input pins can be used with an external VCO. The input may be single-ended or differential. At high frequency, the input impedance to FIN0/FIN1 is low. A resistive pad is recommended for matching.
Table 8-9 list the required programming fields necessary to set up the device for PLL with an external VCO.
FIELD | REGISTER ADDRESS |
FUNCTION | VALUE | SELECTED VALUE |
---|---|---|---|---|
PLL1_NCLK_MUX | 0x13F | Selects the input to the PLL1 N divider. | 1 | Feedback Mux |
PLL2_NCLK_MUX | 0x13F | Selects the input to the PLL2 N divider | 0 | PLL2 P |
FB_MUX_EN | 0x13F | Enables the Feedback Mux. | 1 | Enabled |
FB_MUX | 0x13F | Selects the output of the Feedback Mux. | 0, 1, or 2 | Select between DCLKout6, DCLKout8, SYSREF |
OSCin_PD | 0x140 | Powers down the OSCin port. | 0 | Powered up |
CLKin0_DEMUX | 0x147 | Selects where the output of CLKIN0 is directed. | 2 | PLL1 |
CLKin1_DEMUX | 0x147 | Selects where the output of CLKIN1 is directed. | 0 or 2 | FIN or PLL1 |
VCO_MUX | 0x138 | Selects the VCO 0, 1 or an external VCO | 0 or 1 | VCO 0 or VCO 1 |