参数资料
型号: AD7247ABR
厂商: ANALOG DEVICES INC
元件分类: DAC
英文描述: LC2MOS Dual 12-Bit DACPORTs
中文描述: DUAL, PARALLEL, WORD INPUT LOADING, 5 us SETTLING TIME, 12-BIT DAC, PDSO24
封装: SOIC-24
文件页数: 6/12页
文件大小: 392K
代理商: AD7247ABR
AD7237A/AD7247A
REV. 0
–6–
TERMINOLOGY
RELATIVE ACCURACY (LINEARITY)
Relative Accuracy, or endpoint linearity, is a measure of the
maximum deviation of the DAC transfer function from a
straight line passing through the endpoints of the transfer func-
tion. It is measured after allowing for zero and full-scale errors
and is expressed in LSBs or as a percentage of full-scale reading.
DIFFERENTIAL NONLINEARITY
Differential Nonlinearity is the difference between the measured
change and the ideal 1 LSB change between any two adjacent
codes. A specified differential nonlinearity of
±
1 LSB or less
over the operating temperature range ensures monotonicity.
SINGLE SUPPLY LINEARITY AND GAIN ERROR
The output amplifiers of the AD7237A/AD7247A can have true
negative offsets even when the part is operated from a single
+12 V to +15 V supply. However, because the negative supply
rail (V
SS
) is 0 V, the output cannot actually go negative. Instead,
when the output offset voltage is negative, the output voltage
sits at 0 V, resulting in the transfer function shown in Figure 1.
This “knee” is an offset effect, not a linearity error, and the
transfer function would have followed the dotted line if the out-
put voltage could have gone negative.
Figure 1. Effect of Negative Offset (Single Supply)
Normally, linearity is measured between zero (all 0s input code)
and full scale (all 1s input code) after offset and full scale have
been adjusted out or allowed for, but this is not possible in
single supply operation if the offset is negative, due to the knee
in the transfer function. Instead, linearity of the AD7237A/
AD7247A in the unipolar mode is measured between full scale
and the lowest code which is guaranteed to produce a positive
output voltage. This code is calculated from the maximum
specification for negative offset, i.e., linearity is measured be-
tween Codes 3 and 4095.
UNIPOLAR OFFSET ERROR
Unipolar Offset Error is the measured output voltage from
V
OUTA
or V
OUTB
with all zeros loaded into the DAC latches
when the DACs are configured for unipolar output. It is a com-
bination of the offset errors of the DAC and output amplifier.
BIPOLAR ZERO ERROR
Bipolar Zero Error is the voltage measured at V
OUTA
or V
OUTB
when the DAC is connected in the bipolar mode and loaded
with code 2048. It is due to a combination of offset errors in the
DAC, amplifier offset and mismatch in the application resistors
around the amplifier.
FULL-SCALE ERROR
Full-Scale Error is a measure of the output error when the
amplifier output is at full scale (for the bipolar output range full
scale is either positive or negative full scale). It is measured with
respect to the reference input voltage and includes the offset
errors.
DIGITAL FEEDTHROUGH
Digital Feedthrough is the glitch impulse injected for the digital
inputs to the analog output when the data inputs change state,
but the data in the DAC latches is not changed.
For the AD7237A it is measured with
LDAC
held high. For the
AD7247A it is measured with
CSA
and
CSB
held high.
DIGITAL CROSSTALK
Digital crosstalk is the glitch impulse transferred to the output
of one converter due to a change in digital code to the DAC
latch of the other converter. It is specified in nV secs.
DIGITAL-TO-ANALOG GLITCH IMPULSE
This is the voltage spike that appears at the output of the DAC
when the digital code changes before the output settles to its fi-
nal value. The energy in the glitch is specified in nV secs and is
measured for a 1 LSB change around the major carry transition
(0111 1111 1111 to 1000 0000 0000).
相关PDF资料
PDF描述
AD7247ATQ LC2MOS Dual 12-Bit DACPORTs
AD7248A DIODE SW DUAL BAV99 70V@ 215MA SOT-23
AD7245A LC2MOS 12-Bit DACPORTs
AD7245AAN POLARIZED CAPACITOR (RADIAL)
AD7245AAP LC2MOS 12-Bit DACPORTs
相关代理商/技术参数
参数描述
AD7247ABR-REEL 功能描述:IC DAC 12BIT W/AMP W/BUFF 24SOIC RoHS:否 类别:集成电路 (IC) >> 数据采集 - 数模转换器 系列:DACPORT® 产品培训模块:Data Converter Fundamentals DAC Architectures 标准包装:750 系列:- 设置时间:7µs 位数:16 数据接口:并联 转换器数目:1 电压电源:双 ± 功率耗散(最大):100mW 工作温度:0°C ~ 70°C 安装类型:表面贴装 封装/外壳:28-LCC(J 形引线) 供应商设备封装:28-PLCC(11.51x11.51) 包装:带卷 (TR) 输出数目和类型:1 电压,单极;1 电压,双极 采样率(每秒):143k
AD7247ABRZ 功能描述:IC DAC 12BIT LC2MOS DUAL 24SOIC RoHS:是 类别:集成电路 (IC) >> 数据采集 - 数模转换器 系列:DACPORT® 产品培训模块:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 标准包装:50 系列:- 设置时间:4µs 位数:12 数据接口:串行 转换器数目:2 电压电源:单电源 功率耗散(最大):- 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:8-TSSOP,8-MSOP(0.118",3.00mm 宽) 供应商设备封装:8-uMAX 包装:管件 输出数目和类型:2 电压,单极 采样率(每秒):* 产品目录页面:1398 (CN2011-ZH PDF)
AD7247ABRZ-REEL 功能描述:IC DAC 12BIT AMP/BUFF 24SOIC RoHS:是 类别:集成电路 (IC) >> 数据采集 - 数模转换器 系列:DACPORT® 产品培训模块:Data Converter Fundamentals DAC Architectures 标准包装:750 系列:- 设置时间:7µs 位数:16 数据接口:并联 转换器数目:1 电压电源:双 ± 功率耗散(最大):100mW 工作温度:0°C ~ 70°C 安装类型:表面贴装 封装/外壳:28-LCC(J 形引线) 供应商设备封装:28-PLCC(11.51x11.51) 包装:带卷 (TR) 输出数目和类型:1 电压,单极;1 电压,双极 采样率(每秒):143k
AD7247AQ 功能描述:IC DAC 12BIT W/AMP W/BUFF 24CDIP RoHS:否 类别:集成电路 (IC) >> 数据采集 - 数模转换器 系列:DACPORT® 产品培训模块:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 标准包装:1,000 系列:- 设置时间:1µs 位数:8 数据接口:串行 转换器数目:8 电压电源:双 ± 功率耗散(最大):941mW 工作温度:0°C ~ 70°C 安装类型:表面贴装 封装/外壳:24-SOIC(0.295",7.50mm 宽) 供应商设备封装:24-SOIC W 包装:带卷 (TR) 输出数目和类型:8 电压,单极 采样率(每秒):*
AD7247ATQ 功能描述:数模转换器- DAC IMPROVED 12-BIT DACPORT RoHS:否 制造商:Texas Instruments 转换器数量:1 DAC 输出端数量:1 转换速率:2 MSPs 分辨率:16 bit 接口类型:QSPI, SPI, Serial (3-Wire, Microwire) 稳定时间:1 us 最大工作温度:+ 85 C 安装风格:SMD/SMT 封装 / 箱体:SOIC-14 封装:Tube