参数资料
型号: AD9280ARSZ
厂商: Analog Devices Inc
文件页数: 4/24页
文件大小: 0K
描述: IC ADC CMOS 8BIT 32MSPS 28-SSOP
产品变化通告: AD9280 Pin Configuration Description Change 21/Apr/2010
标准包装: 47
位数: 8
采样率(每秒): 32M
数据接口: 并联
转换器数目: 1
功率耗散(最大): 110mW
电压电源: 单电源
工作温度: -40°C ~ 85°C
安装类型: 表面贴装
封装/外壳: 28-SSOP(0.209",5.30mm 宽)
供应商设备封装: 28-SSOP
包装: 管件
输入数目和类型: 1 个单端,单极
产品目录页面: 780 (CN2011-ZH PDF)
AD9280
–12–
EXTERNAL REFERENCE OPERATION
Using an external reference may provide more flexibility and
improve drift and accuracy. Figures 21 through 23 show ex-
amples of how to use an external reference with the AD9280.
To use an external reference, the user must disable the internal
reference amplifier by connecting the REFSENSE pin to VDD.
The user then has the option of driving the VREF pin, or driv-
ing the REFTS and REFBS pins.
The AD9280 contains an internal reference buffer (A2), that
simplifies the drive requirements of an external reference. The
external reference must simply be able to drive a 10 k
load.
Figure 21 shows an example of the user driving the top and bottom
references. REFTS is connected to a low impedance 2 V source
and REFBS is connected to a low impedance 1 V source. REFTS
and REFBS may be driven to any voltage within the supply as long
as the difference between them is between 1 V and 2 V.
2V
1V
AVDD
2V
1V
MODE
10k
A/D
CORE
4.2k
TOTAL
REFTS
REFBS
10 F
0.1 F
REFTF
REFBF
0.1 F
AIN
0.1 F
AD9280
10k
REF
SENSE
SHA
A2
Figure 21. External Reference Mode—1 V p-p Input Span
Figure 22 shows an example of an external reference generating
2.5 V at the shorted REFTS and REFBS inputs. In this in-
stance, a REF43 2.5 V reference drives REFTS and REFBS. A
resistive divider generates a 1 V VREF signal that is buffered by
A3. A3 must be able to drive a 10 k
, capacitive load. Choose
this op amp based on noise and accuracy requirements.
3.0V
2.0V
2.5V
AVDD
AIN
REFTS
REFTF
REFBF
REFBS
VREF
REFSENSE
MODE
AD9280
0.1 F
A3
1.5k
1k
10 F
0.1 F
+5V
0.1 F
10 F
AVDD
1.0 F
0.1 F
AVDD
0.1 F
AVDD/2
REF43
Figure 22. External Reference Mode—1 V p-p Input
Span 2.5 VCM
Figure 23a shows an example of the external references driving
the REFTF and REFBF pins that is compatible with the
AD876. REFTS is shorted to REFTF and driven by an external
4 V low impedance source. REFBS is shorted to REFBF and
driven by a 2 V source. The MODE pin is connected to GND
in this configuration.
4V
2V
0.1 F
AVDD
10 F
0.1 F
4V
2V
VIN
REFTS
REFTF
REFBF
REFBS
VREF
REFSENSE
MODE
AD9280
Figure 23a. External Reference—2 V p-p Input Span
6
5
8
7
+5V
C3
0.1 F
C4
0.1 F
REFTS
REFTF
C2
10 F
C6
0.1 F
2
3
6
C5
0.1 F
REFBS
REFBF
4
C1
0.1 F
AD9280
REFT
REFB
Figure 23b. Kelvin Connected Reference Using the AD9280
STANDBY OPERATION
The ADC may be placed into a powered down (sleep) mode by
driving the STBY (standby) pin to logic high potential and
holding the clock at logic low. In this mode the typical power
drain is approximately 4 mW.
The ADC will “wake up” in 400 ns (typ) after the standby pulse
goes low.
CLAMP OPERATION
The AD9280ARS features an optional clamp circuit for dc
restoration of video or ac coupled signals. Figure 24 shows the
internal clamp circuitry and the external control signals needed
for clamp operation. To enable the clamp, apply a logic high to
the CLAMP pin. This will close the switch SW1. The clamp
amplifier will then servo the voltage at the AIN pin to be equal
to the clamp voltage applied at the CLAMPIN pin. After the
desired clamp level is attained, SW1 is opened by taking
CLAMP back to a logic low. Ignoring the droop caused by the
input bias current, the input capacitor CIN will hold the dc
voltage at AIN constant until the next clamp interval. The input
resistor RIN has a minimum recommended value of 10
, to
maintain the closed-loop stability of the clamp amplifier.
REV. E
相关PDF资料
PDF描述
ICL3222ECAZ TRANSMITTER/RCVR RS232 LP 20SSOP
LTC1440CMS8 IC COMP W/REF LP SINGLE 8-MSOP
AD7266BCPZ-REEL7 IC ADC 12BIT 2MSPS 3CH 32LFCSP
ICL3222CAZ TRANSMITTER/RCVR RS232 LP 20SSOP
ICL3222EIBZ IC 2DRVR/2RCVR RS232 3V 18-SOIC
相关代理商/技术参数
参数描述
AD9280ARSZRL 功能描述:IC ADC 8BIT CMOS 32MSPS 28SSOP RoHS:是 类别:集成电路 (IC) >> 数据采集 - 模数转换器 系列:- 标准包装:2,500 系列:- 位数:16 采样率(每秒):15 数据接口:MICROWIRE?,串行,SPI? 转换器数目:1 功率耗散(最大):480µW 电压电源:单电源 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:38-WFQFN 裸露焊盘 供应商设备封装:38-QFN(5x7) 包装:带卷 (TR) 输入数目和类型:16 个单端,双极;8 个差分,双极 配用:DC1011A-C-ND - BOARD DELTA SIGMA ADC LTC2494
AD9280-EB 制造商:Analog Devices 功能描述:EVAL BD FOR AD9280 - Bulk
AD9280JRS 制造商:未知厂家 制造商全称:未知厂家 功能描述:Analog-to-Digital Converter, 8-Bit
AD9280JRSRL 制造商:未知厂家 制造商全称:未知厂家 功能描述:Analog-to-Digital Converter, 8-Bit
AD9281 制造商:AD 制造商全称:Analog Devices 功能描述:Dual Channel 8-Bit Resolution CMOS ADC