AD9772A
DIGITAL FILTER SPECIFICATIONS
Parameter
MAXIMUM INPUT DATA RATE (f
DATA
)
DIGITAL FILTER CHARACTERISTICS
Passband Width
1
: 0.005 dB
Passband Width: 0.01 dB
Passband Width: 0.1 dB
Passband Width: –3 dB
LINEAR PHASE (FIR IMPLEMENTATION)
STOPBAND REJECTION
0.606 f
CLOCK
to 1.394 f
CLOCK
GROUP DELAY
2
IMPULSE RESPONSE DURATION
–40 dB
–60 dB
NOTES
1
Excludes sin(x)/x characteristic of DAC.
2
Defined as the number of data clock cycles between impulse input and peak of output response.
Specifications subject to change without notice.
(T
MIN
to T
MAX
, AVDD = 3.3 V, CLKVDD = 3.3 V, PLLVDD = 0 V, DVDD = 3.3 V, I
OUTFS
= 20 mA,
differential transformer coupled output, 50 doubly terminated, unless otherwise noted.)
Min
150
0.401
0.404
0.422
0.479
Typ
Max
Unit
MSPS
f
OUT
/f
DATA
f
OUT
/f
DATA
f
OUT
/f
DATA
f
OUT
/f
DATA
73
21
36
42
dB
Input Clocks
Input Clocks
Input Clocks
0
Table I. Integer Filter Coefficients for Interpolation Filter
(43-Tap Half-Band FIR Filter)
–20
–40
OUTPUT – dB
Lower
Coefficient
H(1)
H(2)
H(3)
H(4)
H(5)
H(6)
H(7)
H(8)
H(9)
H(10)
H(11)
H(12)
H(13)
H(14)
H(15)
H(16)
H(17)
H(18)
H(19)
H(20)
H(21)
H(22)
Upper
Coefficient
H(43)
H(42)
H(41)
H(40)
H(39)
H(38)
H(37)
H(36)
H(35)
H(34)
H(33)
H(32)
H(31)
H(30)
H(29)
H(28)
H(27)
H(26)
H(25)
H(24)
H(23)
Integer
Value
10
0
–31
0
69
0
–138
0
248
0
–419
0
678
0
–1083
0
1776
0
–3282
0
10364
16384
–60
–80
–100
–120
–140
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
FREQUENCY – DC TO
f
DATA
0.8
0.9
1
Figure 2a. FIR Filter Frequency Response—Baseband Mode
1
0.8
NORMALIZED OUTPUT
0.6
0.4
0.2
0
–0.2
–0.4
0
5
10
15
20
25
30
TIME – Samples
35
40
45
Figure 2b. FIR Filter Impulse Response—Baseband Mode
REV. A
–5–
AD [ ANALOG DEVICES ]
