- 您现在的位置：买卖IC网 > PDF目录17039 > EVAL-AD7623CBZ (Analog Devices Inc)BOARD EVALUATION FOR AD7623 PDF资料下载
参数资料
| 型号： | EVAL-AD7623CBZ |
| 厂商： | Analog Devices Inc |
| 文件页数： | 11/28页 |
| 文件大小： | 0K |
| 描述： | BOARD EVALUATION FOR AD7623 |
| 标准包装： | 1 |
| 系列： | PulSAR® |
| ADC 的数量： | 1 |
| 位数： | 16 |
| 采样率（每秒）： | 1.33M |
| 数据接口： | 串行，并联 |
| 输入范围： | ±VREF |
| 在以下条件下的电源（标准）： | 50mW @ 1.33MSPS |
| 工作温度： | -40°C ~ 85°C |
| 已用 IC / 零件： | AD7623 |
| 已供物品： | 板 |
| 相关产品： | AD7623ASTZ-ND - IC ADC 16BIT 1.33MSPS DFF 48LQFP AD7623ACPZ-ND - IC ADC 16BIT 1.33MSPS 48LFCSP AD7623ACPZRL-ND - IC ADC 16BIT 1.33MSPS 48LFCSP AD7623ASTZRL-ND - IC ADC 16BIT 1.33MSPS DFF 48LQFP |
第1页第2页第3页第4页第5页第6页第7页第8页第9页第10页当前第11页第12页第13页第14页第15页第16页第17页第18页第19页第20页第21页第22页第23页第24页第25页第26页第27页第28页
AD7623
Rev. 0 | Page 19 of 28
External Reference (PDBUF = High, PRBUF = High)
To use an external reference directly on the REF pin, PDREF
and PDBUF should both be high. PDREF and PDBUF power
down the internal reference and the internal reference buffer,
respectively.
For improved drift performance, an external reference, such as
the AD780 or ADR431, can be used. The advantages of directly
using the external voltage reference are:
SNR and dynamic range improvement (about 1.7 dB)
resulting from the use of a reference voltage very close to
the supply (2.5 V) instead of a typical 2.048 V reference
when the internal reference is used. This is calculated by
=
048
.
2
50
.
2
log
20
SNR
Power savings when the internal reference is powered
down (PBREF = PDBUF = high).
Reference Decoupling
Whether using an internal or external reference, the AD7623
voltage reference input (REF) has a dynamic input impedance;
therefore, it should be driven by a low impedance source with
efficient decoupling between the REF and REFGND inputs.
This decoupling depends on the choice of the voltage reference,
but usually consists of a low ESR capacitor connected to REF
and REFGND with minimum parasitic inductance. A 10 μF
(X5R, 1206 size) ceramic chip capacitor (or 47 μF tantalum
capacitor) is appropriate when using either the internal
reference or one of these recommended reference voltages:
The low noise, low temperature drift ADR431 and AD780
The low power ADR291
The low cost AD1582
The placement of the reference decoupling is also important to
the performance of the AD7623. The decoupling capacitor
should be mounted on the same side as the ADC right at the
REF pin with a thick PCB trace. The REFGND should also
connect to the reference decoupling capacitor with the shortest
distance.
For applications that use multiple AD7623 devices, it is more
effective to use the internal reference buffer to buffer the
reference voltage.
The voltage reference temperature coefficient (TC) directly
impacts full scale; therefore, in applications where full-scale
accuracy matters, care must be taken with the TC. For instance,
a ±15 ppm/°C TC of the reference changes full-scale by ±1 LSB/°C.
Temperature Sensor
The TEMP pin measures the temperature of the AD7623. To
improve the calibration accuracy over the temperature range,
the output of the TEMP pin is applied to one of the inputs of
the analog switch (such as ADG779), and the ADC itself is used
to measure its own temperature. This configuration is shown
in Figure 28.
05574-028
ADG779
AD8021
CC
ANALOG INPUT
(UNIPOLAR)
AD7623
IN+
TEMPERATURE
SENSOR
TEMP
Figure 28. Use of the Temperature Sensor
POWER SUPPLY
The AD7623 uses three sets of power supply pins: an analog
2.5 V supply AVDD, a digital 2.5 V core supply DVDD, and a
digital input/output interface supply OVDD. The OVDD supply
allows direct interface with any logic working between 2.3 V
and 5.25 V. To reduce the number of supplies needed, the digital
core (DVDD) can be supplied through a simple RC filter from
the analog supply, as shown in Figure 23.
Power Sequencing
The AD7623 is independent of power supply sequencing once
OVDD does not exceed DVDD by more than 0.3 V until
DVDD = 2.3 V during any time; for instance, at power-up or
power-down (see the Absolute Maximum Ratings section).
Additionally, it is very insensitive to power supply variations
over a wide frequency range as shown in Figure 29.
05574-029
FREQUENCY (kHz)
P
S
RR
(dB)
45
75
70
65
60
55
50
1
10
100
1k
10k
EXT REF
INT REF
Figure 29. PSRR vs. Frequency
相关PDF资料 |
PDF描述 |
|---|---|
| RMC05DREN-S93 | CONN EDGECARD 10POS .100 EYELET |
| 0210491052 | CABLE JUMPER 1.25MM .030M 35POS |
| N001-025-BL-R | CABLE PATCH CAT5E BLUE 25' |
| EVAL-AD7622CBZ | BOARD EVALUATION FOR AD7622 |
| RBC08DREN-S93 | CONN EDGECARD 16POS .100 EYELET |
相关代理商/技术参数 |
参数描述 |
|---|---|
| EVAL-AD7623EDZ | 功能描述:BOARD EVAL FOR AD7623 RoHS:是 类别:编程器，开发系统 >> 评估板 - 模数转换器 (ADC) 系列:* 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-AD7625EDZ | 功能描述:数据转换 IC 开发工具 Eval Board 16-BIT 5MSPS ADC I.C 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 |
| EVAL-AD7626EDZ | 功能描述:数据转换 IC 开发工具 Eval Board 16 Bit 10MSPS DIFF ADC 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 |
| EVAL-AD7631CBZ | 制造商:Analog Devices 功能描述:EVALUATION BOARD - Boxed Product (Development Kits) |
| EVAL-AD7631EDZ | 功能描述:BOARD EVAL FOR AD7631 RoHS:是 类别:编程器，开发系统 >> 评估板 - 模数转换器 (ADC) 系列:* 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 |
发布紧急采购，3分钟左右您将得到回复。