AD9000SD AD [Analog Devices], AD9000SD Datasheet - Page 7

• Manufacturer Part Number: AD9000SD
• Description: High Speed 6-Bit A/D Converter
• Manufacturer: AD [Analog Devices]

TYPICAL APPLICATION
The AD9000 is a relatively flexible device that can be config-
ured in a number of ways. One very useful feature of the
AD9000 is the open emitter outputs. The open emitters allow
the outputs of several AD9000s to be OR-wired in stacking
applications for increased resolution. This kind of application
depends on the return-to-zero nature of the output bits when
AIND + V
AD9000, this is not always an advantage. The circuit below
illustrates one method of converting the outputs to nonreturn-
to-zero.
The 10197 (standard 10K ECL logic) hex-AND group senses
the active OVERFLOW output and forces all other bits to logic
REV. A
REF
(overflow). In circuits that employ only one
Figure 6.
–7–
HIGH. The 10151 latch is not required for AD9000 applica-
tions, but it may ease data transfer sensitivities in asynchronous
data collection systems.
The reference driver circuits should provide a low source im-
pedance to prevent noise on the reference inputs from affecting
the AD9000’s accuracy. This is accomplished to a large extent
by adequately decoupling the reference pins to ground. An
improved method is employed below. The reference voltages
(+V
tion. This has the advantages of wide bandwidth (hence low
impedance over a wide frequency range to eliminate high
frequency noise components), and improved temperature
stability.
REF
, –V
REF
) are buffered by a transistor/amplifier combina-
AD9000