125 MSPS Monolithic
350 MHz Sampling Bandwidth
125 MHz Sampling Rate
Excellent Hold Mode Distortion
–75 dB @ 50 MSPS (25 MHz VIN)
–57 dB @ 125 MSPS (50 MHz VIN)
7 ns Acquisition Time to 0.1%
<1 ps Aperture Jitter
66 dB Feedthrough Rejection @ 50 MHz
3.3 nV/√Hz Spectral Noise Density
Direct IF Sampling
Digital Sampling Oscilloscopes
Test Equipment/CCD Testers
DDS DAC Deglitcher
The AD9101 is an extremely accurate, general purpose, high
speed sampling amplifier. Its fast and accurate acquisition speed
allows for a wide range of frequency vs. resolution performance.
The AD9101 is capable of 8 to 12 bits of accuracy at clock rates
of 125 MSPS or 50 MSPS, respectively. This level of perfor-
mance makes it an ideal driver for almost all 8- to 12-bit A/D
encoders on the market today.
In effect, the AD9101 is a track-and-hold with a post amplifier.
This configuration allows the front end sampler to operate at
relatively low signal amplitudes. This results in dramatic im-
provement in both track and hold mode distortion while keeping
The gain-of-four output amplifier has been optimized for fast
and accurate large signal step settling characteristics even when
heavily loaded. This amplifier’s fast Settling Time Linearity
(STL) characteristic causes the amplifier to be transparent to
the low signal level distortion of the sampler. When sampled,
output distortion levels reflect only the distortion performance
of the sampler.
Dramatic SNR and distortion improvements can be realized
when using the AD9101 with high speed flash converters. Flash
converters generally have excellent linearity at dc and low fre-
quencies. However, as signal slew rate increases, their perfor-
mance degrades due to the internal comparators’ aperture delay
variations and finite gain bandwidth product.
FUNCTIONAL BLOCK DIAGRAM
The benefits of using a track-and-hold ahead of a flash converter
have been well known for many years. However, before the
AD9101, there was no track-and-hold amplifier with sufficient
bandwidth and linearity to markedly increase the dynamic per-
formance of such flashes as the AD9002, AD9012, AD9020,
A new application made possible by the AD9101 is direct IF-
to-digital conversion. Utilizing the Nyquist principle, the IF
frequency can be rejected, and the baseband signal can be
recovered. As an example, a 40 MHz IF is modulated by a
10 MHz bandwidth signal. By sampling at 25 MSPS, the signal
of interest is detected.
The AD9101 is offered in commercial and military temperature
ranges. Commercial versions include the AD9101AR in plastic
SOIC and AD9101AE in ceramic LCC. Military devices are
available in ceramic LCC. Contact the factory for availability of
versions in DIP and/or military versions.
1. Guaranteed Hold-Mode Distortion
2. 125 MHz Sampling Rate to 8 Bits; 50 MHz to 12 Bits
3. 350 MHz Sampling Bandwidth
4. Super-Nyquist Sampling Capability
5. Output Offset Adjustable
Information furnished by Analog Devices is believed to be accurate and
reliable. However, no responsibility is assumed by Analog Devices for its
use, nor for any infringements of patents or other rights of third parties
which may result from its use. No license is granted by implication or
otherwise under any patent or patent rights of Analog Devices.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.