AD8137_05 Datasheet, PDF (1/24 Pages) Analog Devices – Low Cost, Low Power 12-Bit Differential ADC Driver

FEATURES
Fully differential
Extremely low power with power-down feature
2.6 mA quiescent supply current @ 5 V
450 µA in power-down mode @ 5 V
High speed
110 MHz large signal 3 dB bandwidth @ G = 1
450 V/µs slew rate
12-bit SFDR performance @ 500 kHz
Fast settling time: 100 ns to 0.02%
Low input offset voltage: ±2.6 mV max
Low input offset current: 0.45 µA max
Differential input and output
Differential-to-differential or single-ended-to-differential
operation
Rail-to-rail output
Adjustable output common-mode voltage
Externally adjustable gain
Wide supply voltage range: 2.7 V to 12 V
Available in small SOIC package
APPLICATIONS
12-bit ADC drivers
Portable instrumentation
Battery-powered applications
Single-ended-to-differential converters
Differential active filters
Video amplifiers
Level shifters
GENERAL DESCRIPTON
The AD8137 is a low cost differential driver with a rail-to-rail
output that is ideal for driving 12-bit ADCs in systems that are
sensitive to power and cost. The AD8137 is easy to apply, and its
internal common-mode feedback architecture allows its output
common-mode voltage to be controlled by the voltage applied
to one pin. The internal feedback loop also provides inherently
balanced outputs as well as suppression of even-order harmonic
distortion products. Fully differential and single-ended-to-
differential gain configurations are easily realized by the
AD8137. External feedback networks consisting of four resistors
determine the amplifier’s closed-loop gain. The power-down
feature is beneficial in critical low power applications.
Low Cost, Low Power 12-Bit
Differential ADC Driver
AD8137
FUNCTIONAL BLOCK DIAGRAM
–IN 1
V_OCM 2
V_S+ 3
+OUT 4
AD8137
8 +IN
7 PD
6 V_S–
5 –OUT
Figure 1.
3
2
G=1
1
0
–1
G=2
G=5
–2
–3
–4
–5
–6
G = 10
–7
–8
–9
–10 _{RG = 1kΩ}
–11 V_{O, dm} = 0.1V p-p
–12
0.1
1
10
100
FREQUENCY (MHz)
Figure 2. Small Signal Response for Various Gains
1000
The AD8137 is manufactured on Analog Devices’ proprietary
second generation XFCB process, enabling it to achieve high
levels of performance with very low power consumption.
The AD8137 is available in the small 8-lead SOIC package and
3 mm × 3 mm LFCSP. It is rated to operate over the extended
industrial temperature range of −40°C to +125°C.
Rev. B
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