ad80164absvz Analog Devices, Inc., ad80164absvz Datasheet - Page 37

• Manufacturer Part Number: ad80164absvz
• Description: Dual, 12-/14-/16-bit,1 Gsps Digital-to-analog Converters
• Manufacturer: Analog Devices, Inc.

Table 19. VCO Frequency Range vs. PLL Band Select Value
PLL Band Select
111111 (63)
111110 (62)
111101 (61)
111100 (60)
111011 (59)
111010 (58)
111001 (57)
111000 (56)
110111 (55)
110110 (54)
110101 (53)
110100 (52)
110011 (51)
110010 (50)
110001 (49)
110000 (48)
101111 (47)
101110 (46)
101101 (45)
101100 (44)
101011 (43)
101010 (42)
101001 (41)
101000 (40)
100111 (39)
100110 (38)
100101 (37)
100100 (36)
100011 (35)
100010 (34)
100001 (33)
100000 (32)
011111 (31)
011110 (30)
011101 (29)
011100 (28)
011011 (27)
011010 (26)
011001 (25)
011000 (24)
010111 (23)
010110 (22)
010101 (21)
010100 (20)
010011 (19)
010010 (18)
010001 (17)
010000 (16)
001111 (15)
001110 (14)
PLL Lock Ranges over Temp, −40°C to at +85°C
f
1975
1956
1938
1923
1902
1883
1870
1848
1830
1822
1794
1779
1774
1748
1729
1730
1699
1685
1684
1651
1640
1604
1596
1564
1555
1521
1514
1480
1475
1439
1435
1402
1397
1361
1356
1324
1317
1287
1282
1250
1245
1215
1210
1182
1174
1149
1141
1115
1109
LOW
VCO Frequency Range in MHz
Auto mode
f
2026
2008
1992
1977
1961
1942
1931
1915
1897
1885
1869
1853
1840
1825
1810
1794
1780
1766
1748
1729
1702
1681
1658
1639
1606
1600
1575
1553
1529
1505
1489
1468
1451
1427
1412
1389
1375
1352
1336
1313
1299
1277
1264
1242
1231
1210
1198
1178
1166
HIGH
Rev. 0 Page 37 of 68
PLL Band Select
001101 (13)
001100 (12)
001011 (11)
001010 (10)
001001 (9)
001000 (8)
000111 (7)
000110 (6)
000101 (5)
000100 (4)
000011 (3)
000010 (2)
000001 (1)
000000 (0)
VCO Frequency Ranges
Because the PLL band covers greater than a 2× frequency range,
there can be two options for the PLL band select: one at the low
end of the range and one at the high end of the range. Under
these conditions, the VCO phase noise is optimal when the user
selects the band select value corresponding to the high end of the
frequency range. Figure 75 shows how the VCO bandwidth and
the optimal VCO frequency varies with the band select value.
VCO Frequency Ranges over Temperature
The specifications given over temperature in Table 19 are for
a single part in a single lot. Part-to-part and lot-to-lot these
specifications can exhibit a mean shift of several register
settings. Systems should be designed to take this potential
shift into account to maintain optimal PLL performance.
In a system that may see wide temperature swings, it may be
necessary for the user to sense the edges of the currently used
lock range. The user would then switch to the next lock range
to avoid potentially losing lock on the PLL.
PLL Lock Ranges over Temp, −40°C to at +85°C
AD9776A/AD9778A/AD9779A
f
1086
1078
1055
1047
1026
1019
998
991
976
963
950
935
922
911
LOW
VCO Frequency Range in MHz
f
1145
1135
1106
1103
1067
1072
1049
1041
1026
1011
996
981
966
951
HIGH