- 您现在的位置：买卖IC网 > PDF目录10212 > AD7731BRZ-REEL (Analog Devices Inc)IC ADC 24BIT SIGMA-DELTA 24-SOIC PDF资料下载
参数资料
| 型号： | AD7731BRZ-REEL |
| 厂商： | Analog Devices Inc |
| 文件页数： | 28/44页 |
| 文件大小： | 0K |
| 描述： | IC ADC 24BIT SIGMA-DELTA 24-SOIC |
| 标准包装： | 1,000 |
| 位数： | 24 |
| 采样率（每秒）： | 6.4k |
| 数据接口： | DSP，串行，SPI? |
| 转换器数目： | 1 |
| 功率耗散（最大）： | 125mW |
| 电压电源： | 模拟和数字 |
| 工作温度： | -40°C ~ 85°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) |
| 输入数目和类型： | 3 个差分，单极；3 个差分，双极；5 个伪差分，单极；5 个伪差分，双极 |
| 配用： | EVAL-AD7731EBZ-ND - BOARD EVALUATION FOR AD7731 |
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页当前第28页第29页第30页第31页第32页第33页第34页第35页第36页第37页第38页第39页第40页第41页第42页第43页第44页
AD7731
–34–
REV. 0
SERIAL INTERFACE
The AD7731’s programmable functions are controlled via a set
of on-chip registers. Access to these registers is via the part’s
serial interface. After power-on or RESET, the device expects a
write to its Communications Register. The data written to this
register determines whether the next operation to the part is a
read or a write operation and also determines to which register
this read or write operation occurs. Therefore, write access to
one of the control registers on the part starts with a write opera-
tion to the Communications Register followed by a write to the
selected register. Reading from the part’s on-chip registers can
either take the form of a single read or continuous read. A single
read from a register consists of a write to the Communications
Register (with RW1 = 0 and RW0 = 1) followed by the read
from the specified register. To perform continuous reads from a
register, write to the Communications Register (with RW1 = 1
and RW0 = 0) to place the part in continuous read mode. The
specified register can then be read from continuously until a
write operation to the Communications Register (with RW1 = 1
and RW0 = 1) which takes the part out of continuous read
mode. When operating in continuous read mode, the part is
continuously monitoring its DIN line. Therefore, the DIN line
should be permanently low to allow the part to stay in continu-
ous read mode. Figure 5 and Figure 6, shown previously, indi-
cate the correct flow diagrams when reading and writing from
the AD7731’s registers.
The AD7731’s serial interface consists of five signals,
CS, SCLK,
DIN, DOUT and
RDY. The DIN line is used for transferring
data into the on-chip registers while the DOUT line is used for
accessing data from the on-chip registers. SCLK is the serial
clock input for the device and all data transfers (either on DIN
or DOUT) take place with respect to this SCLK signal.
Write Operation
The transfer of data into the part is to an input shift register. On
completion of a write operation, data is transferred to the speci-
fied register. This internal transfer will not take place until the
correct number of bits for the specified register have been
loaded to the input shift register. For example, the transfer of
data from the input shift register takes place after eight serial
clock cycles for a DAC Register write while the transfer of data
from the input shift register takes place after 24 serial clock
cycles when writing to the Filter Register. Figure 16 shows a
timing diagram for a write operation to the input shift register of
the AD7731. With the POL input at a logic high, the data is
latched into the input shift register on the rising edge of SCLK.
With the POL input at a logic low, the data is latched into the
input shift register on the falling edge of SCLK.
Figure 16 also shows the
CS input being used to decode the
write operation to the AD7731. However, this
CS input can be
used in a number of different ways. It is possible to operate the
part in three-wire mode where the
CS input is permanently tied
low. In this case, the SCLK line should idle high between data
transfer when the POL input is high and should idle low be-
tween data transfers when the POL input is low. For POL = 1,
the first falling edge of SCLK clocks data from the microcontroller
onto the DIN line of the AD7731. It is then clocked into the
input shift register on the next rising edge of SCLK. For POL = 0,
the first clock edge which clocks data from the microcontroller
onto the DIN line of the AD7731 is a rising edge. It is then
clocked into the input shift register on the next falling edge of
SCLK.
In other microcontroller applications, which require a decoding
of the AD7731,
CS can be generated from a port line. In this
case,
CS would go low well in advance of the first falling edge of
SCLK (POL = 1) or the first rising edge of SCLK (POL = 0).
Clocking of each bit of data is as just described.
In DSP applications, the SCLK is generally a continuous clock.
In these applications, the
CS input for the AD7731 is generated
from a frame synchronization signal from the DSP. For proces-
sors with the rising edge of SCLK as the active edge, the POL
input should be tied high. For processors with the falling edge of
SCLK as the active edge, the POL input should be tied low. In
these applications, the first edge after
CS goes low is the active
edge. The MSB of the data to be shifted into the AD7731 must
be set up prior to this first active edge.
DIN
SCLK
(POL = 1)
CS
MSB
t12
t15
LSB
t16
t14
t11
t13
SCLK
(POL = 0)
t14
t15
Figure 16. Write Cycle Timing Diagram
REV. A
相关PDF资料 |
PDF描述 |
|---|---|
| SP3076EEN-L/TR | IC TXRX RS485/RS422 ESD 14NSOIC |
| AD7667ACPZRL | IC ADC 16BIT UNIPOLAR 48LFCSP |
| SP3075EEN-L/TR | IC TXRX RS485/RS422 ESD 8NSOIC |
| AD7667ASTZRL | IC ADC 16BIT UNIPOLAR 48LQFP |
| SP3074EEN-L/TR | IC TXRX RS485/RS422 ESD 8NSOIC |
相关代理商/技术参数 |
参数描述 |
|---|---|
| AD7731BRZ-REEL7 | 功能描述:IC ADC 24BIT SIGMA-DELTA 24-SOIC RoHS:是 类别:集成电路 (IC) >> 数据采集 - 模数转换器 系列:- 标准包装:1,000 系列:- 位数:12 采样率（每秒）:300k 数据接口:并联 转换器数目:1 功率耗散（最大）:75mW 电压电源:单电源 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 包装:带卷 (TR) 输入数目和类型:1 个单端，单极；1 个单端，双极 |
| AD7731EB | 制造商:AD 制造商全称:Analog Devices 功能描述:Low Noise High Throughput 24-Bit Sigma-Delta ADC(411.99 k) |
| AD7732 | 制造商:AD 制造商全称:Analog Devices 功能描述:2-Channel, +-10 V Input Range, High Throughput, 24-Bit SIGMA- ADC |
| AD7732BRU | 功能描述:IC ADC 24BIT 2-CH 28-TSSOP RoHS:否 类别:集成电路 (IC) >> 数据采集 - 模数转换器 系列:- 标准包装:1,000 系列:- 位数:12 采样率（每秒）:300k 数据接口:并联 转换器数目:1 功率耗散（最大）:75mW 电压电源:单电源 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 包装:带卷 (TR) 输入数目和类型:1 个单端，单极；1 个单端，双极 |
| AD7732BRU-REEL | 制造商:Analog Devices 功能描述:ADC Single Delta-Sigma 15.437ksps 24-bit Serial 28-Pin TSSOP T/R 制造商:Analog Devices 功能描述:ADC SGL DELTA-SIGMA 15.437KSPS 24BIT SERL 28TSSOP - Tape and Reel |
发布紧急采购，3分钟左右您将得到回复。