參數(shù)資料
型號: MAX1444EHJ
廠商: MAXIM INTEGRATED PRODUCTS INC
元件分類: ADC
英文描述: 10-Bit, 40Msps, 3.0V, Low-Power ADC with Internal Reference
中文描述: 10-CH 10-BIT PROPRIETARY METHOD ADC, PARALLEL ACCESS, PQFP32
封裝: 5 X 5 MM, TQFP-32
文件頁數(shù): 18/20頁
文件大小: 401K
代理商: MAX1444EHJ
M
10-Bit, 40Msps, 3.0V, Low-Power
ADC with Internal Reference
18
______________________________________________________________________________________
power-supply sequencing when powering up or down.
With the outputs of the MAX4252 matching better than
0.1%, the buffers and subsequent lowpass filters can
be replicated to support as many as 32 ADCs. For
applications that require more than 32 matched ADCs,
a voltage reference and divider string common to all
converters is highly recommended.
Grounding, Bypassing,
and Board Layout
The MAX1444 requires high-speed board layout design
techniques. Locate all bypass capacitors as close to
the device as possible, preferably on the same side as
the ADC, using surface-mount devices for minimum
inductance. Bypass V
DD
, REFP, REFN, and COM with
two parallel 0.1μF ceramic capacitors and a 2.2μF
bipolar capacitor to GND. Follow the same rules to
bypass the digital supply (OV
DD
) to OGND. Multilayer
boards with separated ground and power planes pro-
duce the highest level of signal integrity. Consider
using a split ground plane arranged to match the physi-
cal location of the analog ground (GND) and the digital
output driver ground (OGND) on the ADC's package.
The two ground planes should be joined at a single
point so that the noisy digital ground currents do not
interfere with the analog ground plane. The ideal loca-
tion of this connection can be determined experimen-
tally at a point along the gap between the two ground
planes that produces optimum results. Make this con-
nection with a low-value, surface-mount resistor (1
to
5
), a ferrite bead, or a direct short. Alternatively, all
ground pins could share the same ground plane if the
ground plane is sufficiently isolated from any noisy, dig-
ital systems ground plane (e.g., downstream output
buffer or DSP ground plane). Route high-speed digital
signal traces away from sensitive analog traces. Keep
all signal lines short and free of 90
°
turns.
Static Parameter Definitions
Integral Nonlinearity
Integral nonlinearity (INL) is the deviation of the values
on an actual transfer function from a straight line. This
straight line can be either a best straight-line fit or a line
drawn between the endpoints of the transfer function
once offset and gain errors have been nullified. The
MAX1444
s static linearity parameters are measured
using the best straight-line fit method.
Differential Nonlinearity
Differential nonlinearity (DNL) is the difference between
an actual step width and the ideal value of 1LSB. A
DNL error specification of less than 1LSB guarantees
no missing codes and a monotonic transfer function.
Dynamic Parameter Definitions
Aperture Jitter
Figure 12 depicts the aperture jitter (t
AJ
), which is the
sample-to-sample variation in the aperture delay.
Aperture Delay
Aperture delay (t
AD
) is the time defined between the
falling edge of the sampling clock and the instant when
an actual sample is taken (Figure 12).
Signal-to-Noise Ratio (SNR)
For a waveform perfectly reconstructed from digital
samples, the theoretical maximum SNR is the ratio of
the full-scale analog input (RMS value) to the RMS
quantization error (residual error). The ideal, theoretical
minimum A/D noise is caused by quantization error only
and results directly from the ADC
s resolution (N bits):
SNR
(MAX)
= (6.02 x N + 1.76)dB
In reality, there are other noise sources besides quanti-
zation noise: thermal noise, reference noise, clock jitter,
etc. SNR is computed by taking the ratio of the RMS
signal to the RMS noise, which includes all spectral
components minus the fundamental, the first five har-
monics, and the DC offset.
HOLD
ANALOG
INPUT
SAMPLED
DATA (T/H)
T/H
t
AD
t
AJ
TRACK
TRACK
CLK
Figure 12. T/H Aperture Timing
相關(guān)PDF資料
PDF描述
MAX1446 10-Bit, 60Msps, 3.0V, Low-Power ADC with Internal Reference
MAX1446EHJ 10-Bit, 60Msps, 3.0V, Low-Power ADC with Internal Reference
MAX1447 1C Remote and Local TEMPERATURE SENSOR with N-Factor and Series Resistance Correction 16-SSOP/QSOP -40 to 125
MAX1496EAI 3.5- and 4.5-Digit, Single-Chip ADCs with LED Drivers
MAX1496EPI 3.5- and 4.5-Digit, Single-Chip ADCs with LED Drivers
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
MAX1444EHJ/V+ 功能描述:模數(shù)轉(zhuǎn)換器 - ADC ANALOG TO DIGITAL CONVERTER RoHS:否 制造商:Texas Instruments 通道數(shù)量:2 結(jié)構(gòu):Sigma-Delta 轉(zhuǎn)換速率:125 SPs to 8 KSPs 分辨率:24 bit 輸入類型:Differential 信噪比:107 dB 接口類型:SPI 工作電源電壓:1.7 V to 3.6 V, 2.7 V to 5.25 V 最大工作溫度:+ 85 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:VQFN-32
MAX1444EHJ/V+T 功能描述:模數(shù)轉(zhuǎn)換器 - ADC 10-Bit 40Msps 3.0V Low-Power ADC with Internal Reference RoHS:否 制造商:Texas Instruments 通道數(shù)量:2 結(jié)構(gòu):Sigma-Delta 轉(zhuǎn)換速率:125 SPs to 8 KSPs 分辨率:24 bit 輸入類型:Differential 信噪比:107 dB 接口類型:SPI 工作電源電壓:1.7 V to 3.6 V, 2.7 V to 5.25 V 最大工作溫度:+ 85 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:VQFN-32
MAX1444EHJ+ 功能描述:模數(shù)轉(zhuǎn)換器 - ADC 10-Bit 40Msps 3V High Speed ADC RoHS:否 制造商:Texas Instruments 通道數(shù)量:2 結(jié)構(gòu):Sigma-Delta 轉(zhuǎn)換速率:125 SPs to 8 KSPs 分辨率:24 bit 輸入類型:Differential 信噪比:107 dB 接口類型:SPI 工作電源電壓:1.7 V to 3.6 V, 2.7 V to 5.25 V 最大工作溫度:+ 85 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:VQFN-32
MAX1444EHJ+T 功能描述:模數(shù)轉(zhuǎn)換器 - ADC 10-Bit 40Msps 3V High Speed ADC RoHS:否 制造商:Texas Instruments 通道數(shù)量:2 結(jié)構(gòu):Sigma-Delta 轉(zhuǎn)換速率:125 SPs to 8 KSPs 分辨率:24 bit 輸入類型:Differential 信噪比:107 dB 接口類型:SPI 工作電源電壓:1.7 V to 3.6 V, 2.7 V to 5.25 V 最大工作溫度:+ 85 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:VQFN-32
MAX1444EHJ-T 功能描述:模數(shù)轉(zhuǎn)換器 - ADC RoHS:否 制造商:Texas Instruments 通道數(shù)量:2 結(jié)構(gòu):Sigma-Delta 轉(zhuǎn)換速率:125 SPs to 8 KSPs 分辨率:24 bit 輸入類型:Differential 信噪比:107 dB 接口類型:SPI 工作電源電壓:1.7 V to 3.6 V, 2.7 V to 5.25 V 最大工作溫度:+ 85 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:VQFN-32