Datasheet

AD9523 Data Sheet
Rev. C | Page 52 of 60
Table 52. PLL1 Output Control (PLL1_OUT, Pin 72)
Address Bits Bit Name Description
0x1BA [7:5] Reserved Reserved
4 PLL1 output CMOS driver
strength
CMOS driver strength
1: weak
0: strong
[3:0] PLL1 output divider 0000: divide-by-1
0001: divide-by-2 (default)
0010: divide-by-4
0100: divide-by-8
1000: divide-by-16
No other inputs permitted
Table 53. PLL1 Output Channel Control
Address Bits Bit Name Description
0x1BB 7 PLL1 output driver power-down PLL1 output driver power-down
[6:4] Reserved Reserved
3 Route VCXO clock to
Channel 3 divider input
1: channel uses VCXO clock. Routes VCXO clock to divider input.
0: channel uses VCO divider output clock
2 Route VCXO clock to
Channel 2 divider input
1: channel uses VCXO clock. Routes VCXO clock to divider input.
0: channel uses VCO divider output clock
1 Route VCXO clock to
Channel 1 divider input
1: channel uses VCXO clock. Routes VCXO clock to divider input.
0: channel uses VCO divider output clock
0 Route VCXO clock to
Channel 0 divider input
1: channel uses VCXO clock. Routes VCXO clock to divider input.
0: channel uses VCO divider output clock
Readback (Address 0x22C to Address 0x22D)
Table 54. Readback Registers (Readback 0 and Readback 1)
Address Bits Bit Name Description
0x22C 7 Status PLL2 reference clock 1: OK
0: off/clocks are missing
6 Status PLL1 feedback clock 1: OK
0: off/clocks are missing
5 Status VCXO 1: OK
0: off/clocks are missing
4 Status REF_TEST 1: OK
0: off/clocks are missing
3 Status REFB 1: OK
0: off/clocks are missing
2
Status REFA
1: OK
0: off/clocks are missing
1 Lock detect PLL2 1: locked
0: unlocked
0 Lock detect PLL1 1: locked
0: unlocked
0x22D [7:4] Reserved Reserved
3 Holdover active 1: holdover is active (both references are missing)
0: normal operation
2 Selected reference
(in auto mode)
Selected reference (applies only when the device automatically selects the reference;
for example, not in manual control mode)
1: REFB
0: REFA
1 Reserved Reserved
0 VCO calibration in progress 1: VCO calibration in progress
0: VCO calibration not in progress