AD8027/AD8028
Rev. C | Page 10 of 24
FREQUENCY (MHz)
0.1
1
10
100
1000
CLOSED-
L
OOP
GAI
(
d
B)
G = +1
VOUT = 200mV p-p
–8
–7
–6
–5
–4
–3
–2
–1
0
1
2
3
4
VICM = VS+ – 0.2V
SELECT = HIGH
VICM = 0V
SELECT = HIGH OR TRI
VICM = VS– + 0.2V
SELECT = TRI
VICM = VS+ – 0.3V
SELECT = HIGH
VICM = VS– + 0.3V
SELECT = TRI
03327-A-015
Figure 16. Small Signal Frequency Response vs.
Input Common-Mode Voltages
FREQUENCY (MHz)
0.001
0.01
0.1
1
10
100
1000
–130
–140
–120
–110
–100
–90
–80
–70
–60
–50
–40
–30
–20
–10
CROS
S
T
ALK
(dB)
03327-A-016
G = +1
VS = 5V
RL = 1kΩ
A TO B
B TO A
CROSSTALK = 20log (VOUT/VIN)
1/2
AD8028
+
U1
R3
1k
Ω
R2
50
Ω
R1
50
Ω
V1
VI
–
1/2
AD8028
+
U2
VOUT
–
Figure 17. AD8028 Crosstalk Output to Output
FREQUENCY (Hz)
OPEN-
L
OOP
GAIN
(
d
B)
PH
A
SE
(
D
egrees)
10
100
1k
10k
100k
1M
10M
100M
1G
–25
–5
15
35
55
75
95
115
135
–10
0
10
20
30
40
50
60
70
80
90
100
110
GAIN
PHASE
03327-A-017
Figure 18. Open-Loop Gain and Phase vs. Frequency
1
10
100
1k
10k
100k
FREQUENCY (Hz)
1M
10M
100M
1G
10
100
CURRE
NT
NOIS
E
(pA/
Hz)
1
10
100
VOLTA
GE
N
OISE
(
n
V/
H
z
)
VOLTAGE
CURRENT
03327-A-018
Figure 19. Voltage and Current Noise vs. Frequency
100
FREQUENCY (MHz)
0.1
1
10
1000
5.9
6.0
6.1
6.2
6.3
6.4
6.5
6.6
6.7
6.8
6.9
CLOSED-
L
OOP
GAIN
(
d
B)
G = +2
RL = 150Ω
VOUT = 2V p-p
VOUT = 200mV p-p
03327-A-019
Figure 20. 0.1 dB Flatness Frequency Response
FREQUENCY (MHz)
0.1
1
20
10
DISTORTION
(
d
B)
–140
–120
–100
–80
–60
–40
–20
G = +1
VOUT = 2V p-p
RL = 1kΩ
SECOND HARMONIC: SOLID LINE
THIRD HARMONIC: DASHED LINE
VS = +3V
VS = +5V
VS = ±5V
03327-A-020
Figure 21. Harmonic Distortion vs. Frequency and Supply Voltage