AD8002 Analog Devices, AD8002 Datasheet - Page 12

• Manufacturer Part Number: AD8002
• Description: Dual 600 MHz, 50 mW Current Feedback Amplifier
• Manufacturer: Analog Devices

Specifications of AD8002

• Vcc-vee: 6V to 12V
• Isy Per Amplifier: 11.5mA
• Packages: DIP,SOIC,SOP
• -3db Bandwidth: 600MHz
• Slew Rate: 1.2kV/µs
• Vos: 2mV
• Ib: 3µA
• # Opamps Per Pkg: 2
• Input Noise (nv/rthz): 2nV/rtHz

AD8002
Driving A-to-D Converters
The AD8002 is well suited for driving high-speed analog-to-
digital converters such as the AD9058. The AD9058 is a dual
8-bit 50 MSPS ADC. In Figure 10, the AD8002 is shown driv-
ing the inputs of the AD9058 which are configured for 0 V to 2 V
ranges. Bipolar input signals are buffered, amplified (–2×), and
offset (by 1.0 V) into the proper input range of the ADC. Using
ANALOG
ANALOG
0.5V
0.5V
IN B
IN A
0.1 F
274
274
1.1k
1.1k
–2V
RZ1, RZ2 = 2,000
50
50
549
AD8002
AD8002
20k
1/2
1/2
549
SIP (8-PKG)
AD707
20k
0.1 F
20
20
ENCODE
0.1 F
40
38
43
6
2
3
1
8
–V
–V
A
A
+V
+V
+V
COMP
ENCODE A
IN B
IN A
REF A
REF B
INT
REF A
REF B
4,19, 21
10
AD9058
(J-LEAD)
the AD9058’s internal 2 V reference connected to both ADCs
as shown in Figure 10 reduces the number of external compo-
nents required to create a complete data acquisition system. The
20 Ω resistors in series with ADC inputs are used to help the
AD8002s drive the 10 pF ADC input capacitance. The AD8002
adds only 100 mW to the power consumption, while not limit-
ing the performance of the circuit.
25, 27, 42
ENCODE B
36
D
D
D
D
7A
7B
0A
0B
(LSB)
(MSB)
(LSB)
(MSB)
+V
–V
S
S
50
5, 9, 22,
24, 37, 41
18
17
16
15
14
13
12
11
28
29
30
31
32
33
34
35
7, 20,
26, 39
0.1 F
74ACT04
0.1 F
1N4001
RZ1
RZ2
–5V
1k
+5V
10pF
CLOCK
8
8