參數(shù)資料
型號: AD9050
廠商: Analog Devices, Inc.
英文描述: RES, MF, STR, 0.25W, 4K75, 1%
中文描述: 10位,40 MSPS/60 MSPS的A / D轉換
文件頁數(shù): 8/12頁
文件大?。?/td> 151K
代理商: AD9050
AD9050
–8–
REV. B
T HE ORY OF OPE RAT ION
Refer to the block diagram on the front page.
T he AD9050 employs a subranging architecture with digital
error correction. T his combination of design techniques en-
sures true 10-bit accuracy at the digital outputs of the converter.
At the input, the analog signal is buffered by a high speed differ-
ential buffer and applied to a track-and-hold (T /H) that holds
the analog value present when the unit is strobed with an
ENCODE command. T he conversion process begins on the
rising edge of this pulse. T he two stage architecture completes a
coarse and then a fine conversion of the T /H output signal.
Error correction and decode logic correct and align data from
the two conversions and present the result as a 10-bit parallel
digital word. Output data are strobed on the rising edge of the
ENCODE command. T he subranging architecture results in
five pipeline delays for the output data. Refer to the AD9050
T iming Diagram.
USING T HE AD9050
3 V System
T he digital input and outputs of the AD9050 can be easily
configured to directly interface to 3 V logic systems. T he en-
code input (Pin 13) is T T L compatible with a logic threshold of
1.5 V. T his input is actually a CMOS stage (refer to Equivalent
Encode Input Stage) with a T T L threshold, allowing operation
with T T L, CMOS and 3 V CMOS logic families. Using 3 V
CMOS logic allows the user to drive the encode directly without
the need to translate to +5 V. T his saves the user power and
board space. As with all high speed data converters, the clock
signal must be clean and jitter free to prevent the degradation of
dynamic performance.
T he AD9050 outputs can also directly interface to 3 V logic
systems. T he digital outputs are standard CMOS stages (refer
to AD9050 Output Stage) with isolated supply pins (Pins 20, 22
V
DD
). By varying the voltage on the V
DD
pins, the digital output
levels vary respectively. By connecting Pins 20 and 22 to the
3 V logic supply, the AD9050 will supply 3 V output levels.
Care should be taken to filter and isolate the output supply of
the AD9050 as noise could be coupled into the ADC, limiting
performance.
Analog Input
T he analog input of the AD9050 is a differential input buffer
(refer to AD9050 Equivalent Analog Input). T he differential
inputs are internally biased at +3.3 V, obviating the need for
external biasing. Excellent performance is achieved whether the
analog inputs are driven single-ended or differential (for best
dynamic performance, impedances at AIN and AINB should
match).
Figure 16 shows typical connections for the analog inputs when
using the AD9050 in a dc coupled system with single ended
signals. All components are powered from a single +5 V supply.
T he AD820 is used to offset the ground referenced input signal
to the level required by the AD9050.
AC coupling of the analog inputs of the AD9050 is easily ac-
complished. Figure 17 shows capacitive coupling of a single
ended signal while Figure 18 shows transformer coupling differ-
entially into the AD9050.
+5V
AD8041
1k
1k
+5V
AD9050
9
10
+5V
1k
AD820
V
–0.5V to +0.5V
1k
0.1μF
0.1μF
Figure 16. Single Supply, Single Ended, DC Coupled
AD9050
+5V
AD8011
1k
1k
+5V
AD9050
9
10
–5V
V
–0.5V to +0.5V
0.1μF
0.1μF
Figure 17. Single Ended, Capacitively Coupled AD9050
+5V
AD8011
1k
1k
+5V
9
10
–5V
V
–0.5V to +0.5V
0.1μF
AD9050
T1-1T
50
Figure 18. Differentially Driven AD9050 Using Trans-
former Coupling
T he AD830 provides a unique method of providing dc level shift
for the analog input. Using the AD830 allows a great deal of
flexibility for adjusting offset and gain. Figure 19 shows the
AD830 configured to drive the AD9050. T he offset is provided
by the internal biasing of the AD9050 differential input (Pin 9).
For more information regarding the AD830, see the AD830
data sheet.
V
–0.5V to +0.5V
1
2
3
4
AD830
+15V
–5V
7
10
9
0.1
μ
F
+5V
AD9050
Figure 19. Level Shifting with the AD830
相關PDF資料
PDF描述
AD9050BR 10-Bit, 40 MSPS/60 MSPS A/D Converter
AD9050BRS 10-Bit, 40 MSPS/60 MSPS A/D Converter
AD9051 10-Bit, 60 MSPS A/D Converter
AD9051-2V 10-Bit, 60 MSPS A/D Converter
AD9051-2VPCB 10-Bit, 60 MSPS A/D Converter
相關代理商/技術參數(shù)
參數(shù)描述
AD9050/PCB 制造商:Analog Devices 功能描述:
AD9050BR 制造商:Analog Devices 功能描述:ADC Single Pipelined 40Msps 10-bit Parallel 28-Pin SOIC W 制造商:Analog Devices 功能描述:A/D Converter (A-D) IC 制造商:Analog Devices 功能描述:1-CH 10-BIT PROPRIETARY METHOD ADC, PARALLEL ACCESS, PDSO28
AD9050BR-REEL 制造商:Analog Devices 功能描述:ADC Single Pipelined 40Msps 10-bit Parallel 28-Pin SOIC W T/R
AD9050BRS 制造商:Analog Devices 功能描述:ADC Single Pipelined 40Msps 10-bit Parallel 28-Pin SSOP 制造商:Analog Devices 功能描述:IC 10-BIT ADC
AD9050BRS-60 制造商:Analog Devices 功能描述:ADC Single Pipelined 60Msps 10-bit Parallel 28-Pin SSOP 制造商:Rochester Electronics LLC 功能描述:10BIT 40MSPS ADC - Bulk