Zakładka z wyszukiwarką danych komponentów
  Polish  ▼
ALLDATASHEET.PL

X  

AD7228ABN Arkusz danych(PDF) 6 Page - Analog Devices

Numer części AD7228ABN
Szczegółowy opis  LC2MOS Octal 8-Bit DAC
Download  8 Pages
Scroll/Zoom Zoom In 100%  Zoom Out
Producent  AD [Analog Devices]
Strona internetowa  http://www.analog.com
Logo AD - Analog Devices

AD7228ABN Arkusz danych(HTML) 6 Page - Analog Devices

  AD7228ABN Datasheet HTML 1Page - Analog Devices AD7228ABN Datasheet HTML 2Page - Analog Devices AD7228ABN Datasheet HTML 3Page - Analog Devices AD7228ABN Datasheet HTML 4Page - Analog Devices AD7228ABN Datasheet HTML 5Page - Analog Devices AD7228ABN Datasheet HTML 6Page - Analog Devices AD7228ABN Datasheet HTML 7Page - Analog Devices AD7228ABN Datasheet HTML 8Page - Analog Devices  
Zoom Inzoom in Zoom Outzoom out
 6 / 8 page
background image
AD7228A
REV. A
–6–
Table II. Unipolar Code Table
DAC Latch Contents
MSB
LSB
Analog Output
1 1 1 1
1 1 1 1
+V
REF
255
256


1 0 0 0
0 0 0 1
+V
REF
129
256


1 0 0 0
0 0 0 0
+V
REF
128
256


=+
V
REF
2
0 1 1 1
1 1 1 1
+V
REF
127
256


0 0 0 0
0 0 0 1
+V
REF
1
256


0 0 0 0
0 0 0 0
0 V
Note: 1 LSB = (VREF)(2
–8) = V
REF
1
256


BIPOLAR OUTPUT OPERATION
Each of the DACs on the AD7228A can be individually config-
ured for bipolar output operation. This is possible using one ex-
ternal amplifier and two resistors per channel. Figure 8 shows a
circuit used to implement offset binary coding (bipolar opera-
tion) with DAC1 of the AD7228A. In this case
V
OUT =
1
+ R2
R1


• D
1 • V REF
() – R2
R1


• V
REF
()
With R1 = R2
VOUT = (2D1 – 1) • (VREF)
where D1 is a fractional representation of the digital word in
latch 1 of the AD7228A. (0
≤ D
1
≤ 255/256)
Figure 8. Bipolar Output Circuit
Table III. Bipolar Code Table
DAC Latch Contents
MSB
LSB
Analog Output
1 1 1 1
1 1 1 1
+V
REF
127
128


1 0 0 0
0 0 0 1
+V
REF
1
128


1 0 0 0
0 0 0 0
0 V
0 1 1 1
1 1 1 1
–V
REF
1
128


0 0 0 0
0 0 0 1
–V
REF
127
128


0 0 0 0
0 0 0 0
–V
REF
128
128


= –V
REF
Mismatch between R1 and R2 causes gain and offset errors, and
therefore, these resistors must match and track over temperature.
Once again, the AD7228A can be operated from single supply
or from dual supplies. Table III shows the digital code versus
output voltage relationship for the circuit of Figure 8 with
R1 = R2.
AC REFERENCE SIGNAL
In some applications it may be desirable to have an ac signal ap-
plied as the reference input to the AD7228A. The AD7228A
has multiplying capability within the upper (+10 V) and lower
(+2 V) limits of reference voltage when operated with dual sup-
plies. Therefore, ac signals need to be ac coupled and biased up
before being applied to the reference input. Figure 9 shows a
sine-wave signal applied to the reference input of the AD7228A.
For input frequencies up to 50 kHz, the output distortion typi-
cally remains less than 0.1%. The typical 3 dB bandwidth for
small signal inputs is 800 kHz.
Figure 9. Applying a AC Signal to the AD7228A
TIMING DESKEW
A common problem in ATE applications is the slowing or
“rounding-off” of signal edges by the time they reach the
pin-driver circuitry. This problem can easily be overcome by
“squaring-up” the edge at the pin-driver. However, since each
edge will not have been “rounded-off” by the same extent, this
“squaring-up” could lead to incorrect timing relationship be-
tween signals. This effect is shown in Figure 10a.
Figure 10a. Time Skewing Due to Slowing of Edges
The circuit of Figure 10b shows how two DACs of the
AD7228A can help in overcoming this problem. The same two
signals are applied to this circuit as were applied in Figure 10b.
The output of each DAC is applied to one input of a high-speed
comparator, and the signals are applied to the other inputs.
Varying the output voltage of the DAC effectively varies the
trigger point at which the comparator flips. Thus the timing re-
lationship between the two signals can be programmably cor-
rected (or deskewed) by varying the code to the DAC of the
AD7228A. In a typical application, the code is loaded to the


Podobny numer części - AD7228ABN

ProducentNumer częściArkusz danychSzczegółowy opis
logo
Analog Devices
AD7228ABN AD-AD7228ABN Datasheet
210Kb / 8P
   LC2MOS Octal 8-Bit DAC Mount Packages
REV. A
AD7228ABN AD-AD7228ABN Datasheet
210Kb / 8P
   LC2MOS Octal 8-Bit DAC
REV. A
AD7228ABN AD-AD7228ABN Datasheet
169Kb / 8P
   LC2MOS Octal 8-Bit DAC
REV. A
AD7228ABN AD-AD7228ABN Datasheet
169Kb / 8P
   LC2MOS Octal 8-Bit DAC
REV. A
AD7228ABN AD-AD7228ABN Datasheet
169Kb / 8P
   LC2MOS Octal 8-Bit DAC
REV. A
More results

Podobny opis - AD7228ABN

ProducentNumer częściArkusz danychSzczegółowy opis
logo
Analog Devices
AD7228UQ AD-AD7228UQ Datasheet
169Kb / 8P
   LC2MOS Octal 8-Bit DAC
REV. A
AD7228KN AD-AD7228KN Datasheet
210Kb / 8P
   LC2MOS Octal 8-Bit DAC
REV. A
AD7228UQ AD-AD7228UQ Datasheet
169Kb / 8P
   LC2MOS Octal 8-Bit DAC
REV. A
AD7228KR AD-AD7228KR Datasheet
210Kb / 8P
   LC2MOS Octal 8-Bit DAC
REV. A
AD7228 AD-AD7228 Datasheet
457Kb / 16P
   LC2MOS Octal 8-Bit DAC
AD7228LP AD-AD7228LP Datasheet
169Kb / 8P
   LC2MOS Octal 8-Bit DAC
REV. A
AD7228A AD-AD7228A Datasheet
210Kb / 8P
   LC2MOS Octal 8-Bit DAC Mount Packages
REV. A
AD7568BPZ AD-AD7568BPZ Datasheet
354Kb / 14P
   LC2MOS Octal 12-Bit DAC
REV. C
AD7568 AD-AD7568 Datasheet
241Kb / 12P
   LC2MOS Octal 12-Bit DAC
REV. B
AD7568BSZ AD-AD7568BSZ Datasheet
354Kb / 14P
   LC2MOS Octal 12-Bit DAC
REV. C
More results


Html Pages

1 2 3 4 5 6 7 8


Arkusz danych Pobierz

Go To PDF Page


Link URL




Polityka prywatności
ALLDATASHEET.PL
Czy Alldatasheet okazała się pomocna?  [ DONATE ] 

O Alldatasheet   |   Reklama   |   Kontakt   |   Polityka prywatności   |   Linki   |   Lista producentów
All Rights Reserved©Alldatasheet.com


Mirror Sites
English : Alldatasheet.com  |   English : Alldatasheet.net  |   Chinese : Alldatasheetcn.com  |   German : Alldatasheetde.com  |   Japanese : Alldatasheet.jp
Russian : Alldatasheetru.com  |   Korean : Alldatasheet.co.kr  |   Spanish : Alldatasheet.es  |   French : Alldatasheet.fr  |   Italian : Alldatasheetit.com
Portuguese : Alldatasheetpt.com  |   Polish : Alldatasheet.pl  |   Vietnamese : Alldatasheet.vn
Indian : Alldatasheet.in  |   Mexican : Alldatasheet.com.mx  |   British : Alldatasheet.co.uk  |   New Zealand : Alldatasheet.co.nz
Family Site : ic2ic.com  |   icmetro.com