AD900 Analog Devices, Inc., AD900 Datasheet - Page 10

• Manufacturer Part Number: AD900
• Description: Highspeed 6-bit Aidconverter
• Manufacturer: Analog Devices, Inc.

ANALOGDEVICES fAX-ON-DEMAND HOTLINE
acquisition circuit must be carefully bypassed to its ground re-
The capacitors which are used should have a high resonant fre-
quency to iI}sure they maintain their characteristics in the range
Every power supply line leading into a high speed PCB or data
tUrn to prevent noise from entering the circuit. Ceramic capaci-
tors, ranging in value from O.OIIJ-Fto O.IIJ-F, should be used
generously in the layoUt, mounted as closely as possible to the
device or circuit being bypassed.
of frequencies involved in the encoding process. Ceramic surface
mount (chip) capacitors meet that requirement and are easily
placed near the package connections.
At least one high quality tanatalum capacitor of 3IJ-F- 20J.l.F
should be assigned to each power supply voltage, mounted as
near as possible to the incoming power pins to minimize low
frequency ripple.
Handling the AD9006/AD9016 Package
Several precautions have been included in the design of the
AD9006/AD9016 converter to help reduce its sensitivity to elec-
trostatic discharge (ESD). But the user should always use nor-
REV. A
-........
Step.
The overflow bit is always 0 ""cept where noted in parentheses ( l. ."iSB INVERT.
and OVERFLOW
.OVERFLOW
"trip point" occurs at approximately
~
00
01
3]
32
33
63
63+
62
I
i
i
!
i
;
Input Volta~;-r
(FS =zl.OV)
.'
-=-1
-1.000,
..0.968
-0.031
+0.031
+0.938
+0.969
+ 1.000
INHIBIT
0.000
INHIBIT
,~"l";
I
i
I
arc considered dc controls. They are tied to ground fof logic" I" and - V, for log;" "0"; their
MSB INVERT '"'I
-
Do-D4 INV = 1
Page
#OVERFLOW
(1)000000#
(0)111111*
000000
000001
Olllll
100001
100000
111110
III III
True
1.3V.
~5
AD9006/AD9016
--
INHIBIT
Binary
MSB INVERT =0
Do-D4 INV =0
"."0."
(1)111111#
(0)000000*
Inverted
-11-
111111
011111
011110
000001
000000
111110
100000
--~-
mal ESD precautions to help insure device reliability and avoid
degrading the unit's performance.
leadless 68-pin ceramic chip carriers; these are shown in the data
(LC), respectively. Both of these packages have been specially
Package options which are available include both leaded and
sheet as leaded ceramic chip carrier and leadless chip carrier
designed to maintain the converter's high frequency parameters
while operating over a standard military temperature range.
Regardless of package type, the top of the package (containing
connected to the device substrate and is designed to be used as a
heat sink. The substrate is connected to - Vs internally; there-
fore the top of the package should be allowed to "float" in volt-
age. The bottom of the package is not connected internally on
the model number and the Analog Devices logo) is internally
the device.
High speed devices such as the AD9006/AD9016 converters
should be soldered into final applications. There is a temptation
to use sockets, but they can limit dynamic performance and
should be used only for evaluation or prototype applications.
Truth Table
.........
MSB INVERT = 0
Do-D. INVERT
Do-D4 INV = 1
(1)100000#
(0)011111 *
000000
000001
100000
011110
011111
10000I
111111
True
Offset Twos Complement
AD9006/AD9016
MSB INVERT = I
Do-D4 INV~O
(1)011111#
(0)100000*
Inverted
011111
011110
000000
100000
111111
111110
100001
m-