參數(shù)資料
型號: HI7190
廠商: Intersil Corporation
英文描述: 24-Bit, High Precision, Sigma Delta A/D Converter(24位高精密∑-Δ A/D轉(zhuǎn)換器)
中文描述: 24位,精度高,Σ-ΔA / D轉(zhuǎn)換(24位高精密Σ-Δ的A / D轉(zhuǎn)換器)
文件頁數(shù): 12/25頁
文件大?。?/td> 472K
代理商: HI7190
12
FN3612.10
June 27, 2006
AV
DD
- 1.8V. Exceeding this range on the V
CM
pin will
compromise the device performance.
Transducer Burn-Out Current Source
The V
INHI
input of the HI7190 contains a 500nA (Typ) current
source which can be turned on/off via the Control Register.
This current source can be used in checking whether a
transducer has burnt-out or become open before attempting
to take measurements on that channel. When the current
source is turned on an additional offset will be created
indicating the presence of a transducer. The current source is
controlled by the BO bit (Bit 4) in the Control Register and is
disabled on power up. See Figure 7 for an applications circuit.
Digital Section Description
A block diagram of the digital section of the HI7190 is shown
in Figure 8. This section includes a low pass decimation
filter, conversion controller, calibration logic, serial interface,
and clock generator.
Digital Filtering
One advantage of digital filtering is that it occurs after the
conversion process and can remove noise introduced during
the conversion. It can not, however, remove noise present
on the analog signal prior to the ADC (which an analog filter
can).
One problem with the modulator/digital filter combination is
that excursions outside the full scale range of the device
could cause the modulator and digital filter to saturate. This
device has headroom built in to the modulator and digital
filter which tolerates signal deviations up to 33% outside of
the full scale range of the device. If noise spikes can drive
the input signal outside of this extended range, it is
recommended that an input analog filter is used or the
overall input signal level is reduced.
Low Pass Decimation Filter
The digital low-pass filter is a Hogenauer (sinc
3
) decimating
filter. This filter was chosen because it is a cost effective low
pass decimating filter that minimizes the need for internal
multipliers and extensive storage and is most effective when
used with high sampling or oversampling rates. Figure 9
shows the frequency characteristics of the filter where f
C
is
the -3dB frequency of the input signal and f
N
is the
programmed notch frequency. The analog modulator sends
a one bit data stream to the filter at a rate of that is
determined by:
f
MODULATOR
= f
OSC
/128
f
MODULATOR
= 78.125kHz for f
OSC
= 10MHz.
The filter then converts the serial modulator data into 40-bit
words for processing by the Hogenauer filter. The data is
decimated in the filter at a rate determined by the CODE
word FP10-FP0 (programed by the user into the Control
Register) and the external clock rate. The equation is:
f
NOTCH
= f
OSC
/(512 x CODE).
The Control Register has 11 bits that select the filter cutoff
frequency and the first notch of the filter. The output data
update rate is equal to the notch frequency. The notch
frequency sets the Nyquist sampling rate of the device while
the -3dB point of the filter determines the frequency
spectrum of interest (f
S
). The FP bits have a usable range of
10 through 2047 where 10 yields a 1.953kHz Nyquist rate.
The Hogenauer filter contains alias components that reflect
around the notch frequency. If the spectrum of the frequency
of interest reaches the alias component, the data has been
aliased and therefore undersampled.
Filter Characteristics
Please note: We have recently discovered a
performance anomaly with the HI7190. The problem
occurs when the digital code for the notch filter is
programmed within certain frequencies. We believe the
error is caused by the calibration logic and the digital
notch code NOT the absolute frequency. The error is
seen when the user applies mid-scale (0V input, Bipolar
mode). With this input, the expected digital output
V
RHI
V
RLO
V
INHI
V
INLO
AV
DD
AV
SS
CURRENT
SOURCE
HI7190
RATIOMETRIC
CONFIGURATION
LOAD CELL
FIGURE 7. BURN-OUT CURRENT SOURCE CIRCUIT
M
SERIAL I/O
SDO
SDIO
SCLK
CS
DRDY
RESET
SYNC
OSC
2
OSC
1
MODULATOR
CLOCK
DIGITAL
FILTER
CALIBRATION
AND CONTROL
CLOCK
GENERATOR
FIGURE 8. DIGITAL SECTION BLOCK DIAGRAM
HI7190
相關(guān)PDF資料
PDF描述
HIN202E(中文) ±15kV, ESD-Protected, +5V Powered, RS-232 Transmitters/Receivers(±15kV ESD防護(hù), +5V電源電壓, RS-232收發(fā)器)
HIN206E(中文) ±15kV, ESD-Protected, +5V Powered, RS-232 Transmitters/Receivers(±15kV ESD防護(hù), +5V電源電壓, RS-232收發(fā)器)
HIN207E(中文) ±15kV, ESD-Protected, +5V Powered, RS-232 Transmitters/Receivers(±15kV ESD防護(hù), +5V電源電壓, RS-232收發(fā)器)
HIN208E(中文) ±15kV, ESD-Protected, +5V Powered, RS-232 Transmitters/Receivers(±15kV ESD防護(hù), +5V電源電壓, RS-232收發(fā)器)
HIN211E(中文) ±15kV, ESD-Protected, +5V Powered, RS-232 Transmitters/Receivers(±15kV ESD防護(hù), +5V電源電壓, RS-232收發(fā)器)
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
HI7190 WAF 制造商:Harris Corporation 功能描述:
HI7190_06 制造商:INTERSIL 制造商全稱:Intersil Corporation 功能描述:24-Bit, High Precision, Sigma Delta A/D Converter
HI7190EVAL 功能描述:EVALUATION PLATFORM HI7190 RoHS:否 類別:編程器,開發(fā)系統(tǒng) >> 評估板 - 模數(shù)轉(zhuǎn)換器 (ADC) 系列:- 產(chǎn)品培訓(xùn)模塊:Obsolescence Mitigation Program 標(biāo)準(zhǔn)包裝:1 系列:- ADC 的數(shù)量:1 位數(shù):12 采樣率(每秒):94.4k 數(shù)據(jù)接口:USB 輸入范圍:±VREF/2 在以下條件下的電源(標(biāo)準(zhǔn)):- 工作溫度:-40°C ~ 85°C 已用 IC / 零件:MAX11645 已供物品:板,軟件
HI7190IB 功能描述:IC ADC 24BIT PROGBL SER 20-SOIC RoHS:否 類別:集成電路 (IC) >> 數(shù)據(jù)采集 - 模數(shù)轉(zhuǎn)換器 系列:- 產(chǎn)品培訓(xùn)模塊:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 標(biāo)準(zhǔn)包裝:2,500 系列:- 位數(shù):12 采樣率(每秒):3M 數(shù)據(jù)接口:- 轉(zhuǎn)換器數(shù)目:- 功率耗散(最大):- 電壓電源:- 工作溫度:- 安裝類型:表面貼裝 封裝/外殼:SOT-23-6 供應(yīng)商設(shè)備封裝:SOT-23-6 包裝:帶卷 (TR) 輸入數(shù)目和類型:-
HI7190IBZ 功能描述:模數(shù)轉(zhuǎn)換器 - ADC ADC 24BIT 10MHZ SIGMADELTA 20 IND 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