- 您现在的位置：买卖IC网 > PDF目录10212 > AD7357BRUZ-RL (Analog Devices Inc)IC ADC 14BITDUAL 4.MSPS 16TSSOP PDF资料下载
参数资料
| 型号： | AD7357BRUZ-RL |
| 厂商： | Analog Devices Inc |
| 文件页数： | 8/21页 |
| 文件大小： | 0K |
| 描述： | IC ADC 14BITDUAL 4.MSPS 16TSSOP |
| 设计资源： | DC-Coupled, Single-Ended-to-Differential Conversion Using AD8138 and AD7357 (CN0061) |
| 标准包装： | 2,500 |
| 位数： | 14 |
| 采样率（每秒）： | 4.2M |
| 数据接口： | DSP，MICROWIRE?，QSPI?，串行，SPI? |
| 转换器数目： | 2 |
| 功率耗散（最大）： | 59mW |
| 电压电源： | 单电源 |
| 工作温度： | -40°C ~ 85°C |
| 安装类型： | 表面贴装 |
| 封装/外壳： | 16-TSSOP（0.173"，4.40mm 宽） |
| 供应商设备封装： | 16-TSSOP |
| 包装： | 带卷 (TR) |
| 输入数目和类型： | 2 个差分，双极 |
AD7357
Rev. B | Page 15 of 20
MODES OF OPERATION
The AD7357 mode of operation is selected by controlling the
logic state of the CS signal during a conversion. There are three
possible modes of operation: normal mode, partial power-down
mode, and full power-down mode. After a conversion has been
initiated, the point at which CS is pulled high determines which
power-down mode, if any, the device enters. Similarly, if already
in a power-down mode, CS can control whether the device
returns to normal operation or remains in a power-down mode.
These modes of operation are designed to provide flexible power
management options. These options can be chosen to optimize
the power dissipation/throughput rate ratio for the differing
application requirements.
NORMAL MODE
Normal mode is intended for applications needing the fastest
throughput rates. The user does not have to worry about any
power-up times because the AD7357 remains fully powered at
all times. Figure 24 shows the general diagram of the operation
of the AD7357 in this mode.
SCLK
LEADING ZEROS + CONVERSION RESULT
CS
1
10
14
07
75
7-
01
8
SDATAA
SDATAB
Figure 24. Normal Mode Operation
The conversion is initiated on the falling edge of CS, as described
in the
section. To ensure that the part remains
fully powered up at all times,
CS must remain low until at least
10 SCLK falling edges have elapsed after the falling edge of CS.
If CS is brought high any time after the 10th SCLK falling edge
but before the 16th SCLK falling edge, the part remains powered
up, but the conversion is terminated and SDATA and SDATAB
go back into three-state. 16 serial clock cycles are required to
complete the conversion and access the conversion result for
the AD7357. The SDATA lines do not return to three-state
after 16 SCLK cycles have elapsed, but instead do so when
A
CS
is brought high again. If CS is left low for another 2 SCLK
cycles, two trailing zeros are clocked out after the data. If CS
is left low for a further 16 SCLK cycles, the result for the other
ADC on board is also accessed on the same SDATA line as
shown in
(see the
section).
When 32 SCLK cycles have elapsed, the SDATA line returns to
three-state on the 32nd SCLK falling edge. If CS is brought high
prior to this, the SDATA line returns to three-state at that point.
Thus, CS may idle low after 32 SCLK cycles until it is brought
high again sometime prior to the next conversion, if so desired,
because the bus still returns to three-state upon completion of
the dual result read.
When a data transfer is complete and SDATAA and SDATAB
have returned to three-state, another conversion can be initiated
after the quiet time, tQUIET, has elapsed by bringing CS low again
(assuming the required acquisition time has been allowed).
PARTIAL POWER-DOWN MODE
This mode is intended for use in applications where slower
throughput rates are required. Either the ADC is powered
down between each conversion, or a series of conversions
can be performed at a high throughput rate and the ADC is
then powered down for a relatively long duration between
these bursts of several conversions. When the AD7357 is in
partial power-down, all analog circuitry is powered down
except for the on-chip reference and reference buffers.
To enter partial power-down mode, the conversion process
must be interrupted by bringing CS high anywhere after the
second falling edge of SCLK and before the 10th falling edge of
SCLK, as shown in
. When
CS is brought high in this
window of SCLKs, the part enters partial power-down mode,
the conversion that was initiated by the falling edge of CS is
terminated, and SDATA and SDATAB go back into three-state. If
A
CS is brought high before the second SCLK falling edge, the
part remains in normal mode and does not power down. This
avoids accidental power-down due to glitches on the CS line.
SCLK
THREE-STATE
CS
SDATAA
SDATAB
11
10
4
2
0
775
7-
0
19
Figure 25. Entering Partial Power-Down Mode
To exit this mode of operation and to power up the AD7357
again, perform a dummy conversion. On the falling of CS, the
device begins to power up and continues to power up as long
as CS is held low until after the falling edge of the 10th SCLK.
The device is fully powered up after approximately 200 ns
elapses (or one full conversion), and valid data results from the
next conversion, as shown in
. If
CS is brought high
before the second falling edge of SCLK, the AD7357 again goes
into partial power-down mode. This avoids accidental power-
up due to glitches on the CS line. Although the device may
begin to power up on the falling edge of CS, it powers down
again on the rising edge of CS. If the AD7357 is already in
partial power-down mode and CS is brought high between
the second and 10th falling edges of SCLK, the device enters
full power-down mode.
相关PDF资料 |
PDF描述 |
|---|---|
| SP3083EEN-L/TR | IC TXRX RS485/RS422 ESD 14NSOIC |
| SP3081EEN-L/TR | IC TXRX RS485/RS422 ESD 8NSOIC |
| SP3080EEN-L/TR | IC TXRX RS485/RS422 ESD 14NSOIC |
| AD7661ACPZ | IC ADC 16BIT W/REF 48LFCSP |
| SP3077EEN-L/TR | IC TXRX RS485/RS422 ESD 8NSOIC |
相关代理商/技术参数 |
参数描述 |
|---|---|
| AD7357WYRUZ | 制造商:Analog Devices 功能描述:ADC Dual SAR 4.2Msps 14-bit Serial 16-Pin TSSOP 制造商:Analog Devices 功能描述:14-BIT DUAL DIFF SIMULT 5 MSPS ADC I.C. - Rail/Tube 制造商:Rochester Electronics LLC 功能描述: 制造商:Analog Devices 功能描述:IC ADC 14BIT SRL 5MSPS 16TSSOP 制造商:Analog Devices 功能描述:Analog to Digital Converters - ADC 14-Bit Dual Diff Simult 5 MSPS 制造商:Analog Devices 功能描述:14-Bit Dual Diff Simult 5 MSPS ADC I.C. |
| AD7357WYRUZ-RL | 功能描述:模数转换器 - ADC 14-Bit Dual Diff Simult 5 MSPS RoHS:否 制造商:Analog Devices 通道数量: 结构: 转换速率: 分辨率: 输入类型: 信噪比: 接口类型: 工作电源电压: 最大工作温度: 安装风格: 封装 / 箱体: |
| AD7357YRUZ | 功能描述:IC ADC DUAL14BIT 4.2MSPS 16TSSOP 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 系列:- 位数:14 采样率（每秒）:83k 数据接口:串行，并联 转换器数目:1 功率耗散（最大）:95mW 电压电源:双 ± 工作温度:0°C ~ 70°C 安装类型:通孔 封装/外壳:28-DIP（0.600"，15.24mm） 供应商设备封装:28-PDIP 包装:管件 输入数目和类型:1 个单端，双极 |
| AD7357YRUZ-500RL7 | 功能描述:IC ADC DUAL14BIT 4.2MSPS 16TSSOP 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 |
| AD7357YRUZ-RL | 功能描述:IC ADC DUAL14BIT 4.2MSPS 16TSSOP 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 |
发布紧急采购，3分钟左右您将得到回复。