参数资料
型号: EVAL-AD7690SDZ
厂商: Analog Devices Inc
文件页数: 4/24页
文件大小: 0K
描述: BOARD EVAL FOR AD7690
标准包装: 1
系列: PulSAR®
ADC 的数量: 1
位数: 18
采样率(每秒): 400k
数据接口: DSP,MICROWIRE?,QSPI?,串行,SPI?
输入范围: ±VREF
在以下条件下的电源(标准): 17mW @ 100kSPS
工作温度: -40°C ~ 85°C
已用 IC / 零件: AD7690
已供物品:
AD7690
Rev. B | Page 12 of 24
THEORY OF OPERATION
SW+
MSB
65,536C
IN+
LSB
COMP
CONTROL
LOGIC
SWITCHES CONTROL
BUSY
OUTPUT CODE
CNV
REF
GND
IN–
4C
2C
C
131,072C
SW–
MSB
65,536C
LSB
4C
2C
C
131,072C
0
57
92
-00
6
Figure 24. ADC Simplified Schematic
CIRCUIT INFORMATION
The AD7690 is a fast, low power, single-supply, precise, 18-bit
ADC using a successive approximation architecture.
The AD7690 is capable of converting 400,000 samples per
second (400 kSPS) and powers down between conversions.
When operating at 1 kSPS, for example, it consumes 50 μW
typically, ideal for battery-powered applications.
The AD7690 provides the user with an on-chip track-and-hold
and does not exhibit pipeline delay or latency, making it ideal
for multiple multiplexed channel applications.
The AD7690 is specified from 4.75 V to 5.25 V and can be
interfaced to any 1.8 V to 5 V digital logic family. It is housed in
a 10-lead MSOP or a tiny 10-lead QFN (LFCSP) that allows
space savings and flexible configurations.
It is pin-for-pin compatible with the 18-bit AD7691 and AD7982
and the 16-bit AD7687, AD7688, and AD7693.
CONVERTER OPERATION
The AD7690 is a successive approximation ADC based on a
charge redistribution DAC. Figure 24 shows the simplified
schematic of the ADC. The capacitive DAC consists of two
identical arrays of 18 binary-weighted capacitors, which are
connected to the two comparator inputs.
During the acquisition phase, terminals of the array tied to the
comparator’s input are connected to GND via SW+ and SW.
All independent switches are connected to the analog inputs.
Thus, the capacitor arrays are used as sampling capacitors and
acquire the analog signal on the IN+ and IN inputs. When the
acquisition phase is complete and the CNV input goes high, a
conversion phase is initiated. When the conversion phase
begins, SW+ and SW are opened first. The two capacitor
arrays are then disconnected from the inputs and connected to
the GND input. Therefore, the differential voltage between the
IN+ and IN inputs captured at the end of the acquisition phase
is applied to the comparator inputs, causing the comparator to
become unbalanced. By switching each element of the capacitor
array between GND and REF, the comparator input varies by
binary-weighted voltage steps (VREF/2, VREF/4 ... VREF/262,144).
The control logic toggles these switches, starting with the MSB,
to bring the comparator back into a balanced condition. After
the completion of this process, the part returns to the
acquisition phase, and the control logic generates the ADC
output code and a busy signal indicator.
Because the AD7690 has an on-board conversion clock, the
serial clock, SCK, is not required for the conversion process.
相关PDF资料
PDF描述
0210490944 CABLE JUMPER 1.25MM .051M 25POS
EVAL-AD7980SDZ BOARD EVAL FOR AD7980
PH50S2412 CONVERTER DC/DC 12V 50W 6-PIN
1624094-9 INDUCTOR 220UH 100MA 1812
EVAL-AD7685SDZ BOARD EVAL FOR AD7685
相关代理商/技术参数
参数描述
EVAL-AD7691CBZ 功能描述:BOARD EVALUATION FOR AD7691CBZ RoHS:是 类别:编程器,开发系统 >> 评估板 - 模数转换器 (ADC) 系列:PulSAR® 产品培训模块:Obsolescence Mitigation Program 标准包装:1 系列:- ADC 的数量:1 位数:12 采样率(每秒):94.4k 数据接口:USB 输入范围:±VREF/2 在以下条件下的电源(标准):- 工作温度:-40°C ~ 85°C 已用 IC / 零件:MAX11645 已供物品:板,软件
EVAL-AD7691SDZ 功能描述:BOARD EVAL FOR AD7691 RoHS:是 类别:编程器,开发系统 >> 评估板 - 模数转换器 (ADC) 系列:PulSAR® 产品培训模块:Obsolescence Mitigation Program 标准包装:1 系列:- ADC 的数量:1 位数:12 采样率(每秒):94.4k 数据接口:USB 输入范围:±VREF/2 在以下条件下的电源(标准):- 工作温度:-40°C ~ 85°C 已用 IC / 零件:MAX11645 已供物品:板,软件
EVAL-AD7693CB 制造商:Analog Devices 功能描述:EVAL KIT FOR 16BIT, 0.5 LSB, 500 KSPS PULSARDIFFERENTIAL ADC - Bulk
EVAL-AD7693CBZ 功能描述:BOARD EVALUATION FOR AD7693 RoHS:是 类别:编程器,开发系统 >> 评估板 - 模数转换器 (ADC) 系列:PulSAR® 产品培训模块:Obsolescence Mitigation Program 标准包装:1 系列:- ADC 的数量:1 位数:12 采样率(每秒):94.4k 数据接口:USB 输入范围:±VREF/2 在以下条件下的电源(标准):- 工作温度:-40°C ~ 85°C 已用 IC / 零件:MAX11645 已供物品:板,软件
EVAL-AD7693SDZ 功能描述:数据转换 IC 开发工具 EVAL BOARD 16-bit ADC 500kSPS RoHS:否 制造商:Texas Instruments 产品:Demonstration Kits 类型:ADC 工具用于评估:ADS130E08 接口类型:SPI 工作电源电压:- 6 V to + 6 V