参数资料
型号: MAX194BEWE+T
厂商: Maxim Integrated Products
文件页数: 15/24页
文件大小: 0K
描述: IC ADC 14BIT 85KSPS 16-SOIC
产品培训模块: Lead (SnPb) Finish for COTS
Obsolescence Mitigation Program
标准包装: 1,000
位数: 14
采样率(每秒): 85k
数据接口: QSPI?,串行,SPI?
转换器数目: 1
功率耗散(最大): 80mW
电压电源: 模拟和数字,双 ±
工作温度: -40°C ~ 85°C
安装类型: 表面贴装
封装/外壳: 16-SOIC(0.295",7.50mm 宽)
供应商设备封装: 16-SOIC W
包装: 带卷 (TR)
输入数目和类型: 1 个单端,单极;1 个单端,双极
MAX194
14-Bit, 85ksps ADC with 10A Shutdown
22
______________________________________________________________________________________
MAX194
10
F
VDDD
VDDA
VSSA
VSSD
AGND
DGND
5V
0.1
F
0.1
F
10
F
10
10
10
F
0.1
F
0.1
F
10
F
100
0.01
1
10
100
1000
10,000 100,000
0.1
MAX194-FIG23
CONVERSIONS PER SECOND
POWER
DISSIPATION
(mW)
1
10
20
s WAKE-UP DELAY
0.05LSB ERROR
3.2
s WAKE-UP DELAY
0.1LSB ERROR
graph of theoretical power consumption vs. conver-
sions per second for the MAX194 that assumes the
conversion clock is 1.7MHz and the converter is shut
down as much as possible between conversions.
Stop CLK before shutting down the MAX194. CLK must
be stopped without generating short clock pulses. Short
CLK pulses (less than 150ns), or shutting down the
MAX194 without stopping CLK, may adversely affect the
MAX194’s internal calibration data. In applications
where CLK is free-running and asynchronous, use the
circuit of Figure 24 to stop CLK cleanly.
To minimize the time required to settle and perform a
conversion, shut the converter down only after a con-
version is finished and the desired mode (unipolar or
bipolar) has been set. This ensures that the sampling
capacitor array is properly connected to the input sig-
nal. If shut down in mid-conversion, when awakened,
the MAX194 finishes the old conversion, allows four
clock (CLK) cycles for input acquisition, then begins
the new conversion.
_____________Dynamic Performance
High-speed sampling capability, 85ksps throughput,
and wide dynamic range make the MAX194 ideal for
AC applications and signal processing. To support
these and other related applications, Fast Fourier
Transform (FFT) test techniques are used to guarantee
the ADC’s dynamic frequency response, distortion, and
noise at the rated throughput. Specifically, this involves
applying a low-distortion sine wave to the ADC input
and recording the digital conversion results for a
specified time. The data is then analyzed using an FFT
algorithm, which determines its spectral content.
Conversion errors are then seen as spectral elements
other than the fundamental input frequency.
Signal-to-Noise Ratio and
Effective Number of Bits
Signal-to-Noise Ratio (SNR) is the ratio between the
RMS amplitude of the fundamental input frequency to
the RMS amplitude of all other ADC output signals. The
output band is limited to frequencies above DC and
below one-half the ADC sample rate. This usually (but
not always) includes distortion as well as noise compo-
nents. For this reason, the ratio is sometimes referred to
as Signal-to-Noise + Distortion (SINAD).
The theoretical minimum ADC noise is caused by quan-
tization error and is a direct result of the ADC’s resolu-
tion: SNR = (6.02N + 1.76)dB, where N is the number
of bits of resolution. A perfect 14-bit ADC can, there-
fore, do no better than 86dB. An FFT plot of the output
shows the output level in various spectral bands. Figure
25 shows the result of sampling a pure 1kHz sinusoid at
85ksps with the MAX194.
By transposing the equation that converts resolution to
SNR, we can, from the measured SNR, determine the
effective resolution or the “effective number of bits” the
ADC provides: N = (SNR - 1.76) / 6.02. Substituting
SINAD for SNR in this formula results in a better
Figure 22. Supply Bypassing and Grounding
Figure 23. Power Dissipation vs. Conversions/sec When
Shutting the MAX194 Down Between Conversions
相关PDF资料
PDF描述
VE-J4X-MX-F4 CONVERTER MOD DC/DC 5.2V 75W
MX7828LCWI+ IC ADC 8BIT HS 28-SOIC
MS27473P16B55S CONN PLUG 55POS STRAIGHT W/SCKT
VE-J4X-MX-F3 CONVERTER MOD DC/DC 5.2V 75W
VE-J4X-MX-F2 CONVERTER MOD DC/DC 5.2V 75W
相关代理商/技术参数
参数描述
MAX194BMDE 功能描述:模数转换器 - ADC RoHS:否 制造商:Texas Instruments 通道数量:2 结构:Sigma-Delta 转换速率:125 SPs to 8 KSPs 分辨率:24 bit 输入类型:Differential 信噪比:107 dB 接口类型:SPI 工作电源电压:1.7 V to 3.6 V, 2.7 V to 5.25 V 最大工作温度:+ 85 C 安装风格:SMD/SMT 封装 / 箱体:VQFN-32
MAX194EVC16-DIP 功能描述:模数转换器 - ADC Programmers, Development Systems RoHS:否 制造商:Texas Instruments 通道数量:2 结构:Sigma-Delta 转换速率:125 SPs to 8 KSPs 分辨率:24 bit 输入类型:Differential 信噪比:107 dB 接口类型:SPI 工作电源电压:1.7 V to 3.6 V, 2.7 V to 5.25 V 最大工作温度:+ 85 C 安装风格:SMD/SMT 封装 / 箱体:VQFN-32
MAX194EVKIT-DIP 功能描述:数据转换 IC 开发工具 Programmers, Development Systems 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
MAX19505ETM+ 功能描述:模数转换器 - ADC 8-Bit 2Ch 65Msps 1.8V Precision ADC RoHS:否 制造商:Texas Instruments 通道数量:2 结构:Sigma-Delta 转换速率:125 SPs to 8 KSPs 分辨率:24 bit 输入类型:Differential 信噪比:107 dB 接口类型:SPI 工作电源电压:1.7 V to 3.6 V, 2.7 V to 5.25 V 最大工作温度:+ 85 C 安装风格:SMD/SMT 封装 / 箱体:VQFN-32
MAX19505ETM+T 功能描述:模数转换器 - ADC 8-Bit 2Ch 65Msps 1.8V Precision ADC RoHS:否 制造商:Texas Instruments 通道数量:2 结构:Sigma-Delta 转换速率:125 SPs to 8 KSPs 分辨率:24 bit 输入类型:Differential 信噪比:107 dB 接口类型:SPI 工作电源电压:1.7 V to 3.6 V, 2.7 V to 5.25 V 最大工作温度:+ 85 C 安装风格:SMD/SMT 封装 / 箱体:VQFN-32