SNAS605AS March 2013 – May 2020 LMK04821 , LMK04826 , LMK04828
PRODUCTION DATA.
This register controls the PLL1 phase detector.
BIT | NAME | POR DEFAULT | DESCRIPTION | |
---|---|---|---|---|
7:6 | PLL1_WND_SIZE | 3 | PLL1_WND_SIZE sets the window size used for digital lock detect for PLL1. If the phase error between the reference and feedback of PLL1 is less than specified time, the PLL1 lock counter increments. | |
Field Value | Definition | |||
0 (0x00) | 4 ns | |||
1 (0x01) | 9 ns | |||
2 (0x02) | 19 ns | |||
3 (0x03) | 43 ns | |||
5 | PLL1_CP_TRI | 0 | This bit allows for the PLL1 charge pump output pin, CPout1, to be placed into TRI-STATE.
0: PLL1 CPout1 is active 1: PLL1 CPout1 is at TRI-STATE |
|
4 | PLL1_CP_POL | 1 | PLL1_CP_POL sets the charge pump polarity for PLL1. Many VCXOs use positive slope.
A positive-slope VCXO increases output frequency with increasing voltage. A negative-slope VCXO decreases output frequency with increasing voltage. 0: Negative-slope VCO/VCXO 1: Positive-slope VCO/VCXO |
|
3:0 | PLL1_CP_GAIN | 4 | This bit programs the PLL1 charge pump output current level. | |
Field Value | Gain | |||
0 (0x00) | 50 µA | |||
1 (0x01) | 150 µA | |||
2 (0x02) | 250 µA | |||
3 (0x03) | 350 µA | |||
4 (0x04) | 450 µA | |||
... | ... | |||
14 (0x0E) | 1450 µA | |||
15 (0x0F) | 1550 µA |