AD8351
Low Distortion
Differential RF/IF Amplifier
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FEATURES
–3 dB Bandwidth of 2.2 GHz for A
V
= 12 dB
Single Resistor Programmable Gain
0 dB ≤ A
V
≤ 26 dB
Differential Interface
Low Noise Input Stage 2.7 nV/√Hz @ A
V
= 10 dB
Low Harmonic Distortion
–79 dBc Second @ 70 MHz
–81 dBc Third @ 70 MHz
OIP3 of 31 dBm @ 70 MHz
Single-Supply Operation: 3 V to 5.5 V
Low Power Dissipation: 28 mA @ 5 V
Adjustable Output Common-Mode Voltage
Fast Settling and Overdrive Recovery
Slew Rate of 13,000 V/s
Power-Down Capability
10-Lead MSOP Package
APPLICATIONS
Differential ADC Drivers
Single-Ended-to-Differential Conversion
IF Sampling Receivers
RF/IF Gain Blocks
SAW Filter Interfacing
FUNCTIONAL BLOCK DIAGRAM
VOCM
VPOS
OPHI
OPLO
COMM
PWUP
RGP1
INHI
INLO
RGP2
AD8351
BIAS CELL
GENERAL DESCRIPTION
The AD8351 is a low cost differential amplifier useful in RF and
IF applications up to 2.2 GHz. The voltage gain can be set from
unity to 26 dB using a single external gain resistor. The AD8351
provides a nominal 150 Ω differential output impedance. The
excellent distortion performance and low noise characteristics of
this device allow for a wide range of applications.
The AD8351 is designed to satisfy the demanding performance
requirements of communications transceiver applications. The
device can be used as a general-purpose gain block, an ADC driver,
051015 20 25 30 35
2
3
+
RG
AD8351
100nF
100nF
25⍀
25⍀
AD6645
14-BIT ADC
INHI
INLO
200⍀
AD8351
AD8351 WITH 10 dB OF
GAIN DRIVING THE
AD6645 (R
L
= 1k⍀)
ANALOG INPUT: 70MHz
ENCODE : 80MHz
SNR : 69.1dB
FUND : –1.1dBFS
HD2 : –78.5dBc
HD3 : –80.7dBc
THD : –75.9dBc
SFDR : 78.2dBc
0
–10
–20
–40
–30
–50
–60
–70
–80
–90
–120
–100
–130
–110
and a high speed data interface driver, among other functions. The
AD8351 can also be used as a single-ended-to-differential
amplifier with similar distortion products as in the differential
configuration. The exceptionally good distortion performance
makes the AD8351 an ideal solution for 12-bit and 14-bit IF
sampling receiver designs.
Fabricated in ADI’s high speed XFCB process, the AD8351
has high bandwidth that provides high frequency performance
and low distortion. The quiescent current of the AD8351 is 28 mA
typically. The AD8351 amplifier comes in a compact 10-lead
MSOP package and will operate over the temperature range
of –40°C to +85°C.
REV. B
