The AD7912/AD7922 are 10-bit and 12-bit, high speed, low power, 2-channel, successive-approximation ADCs respectively. The parts operate from a single 2.35 V to 5.25 V power supply and feature throughput rates up to 1 MSPS. The parts contain a low-noise, wide bandwidth track/hold amplifier, which can handle input frequencies in excess of 6 MHz.
The conversion process and data acquisition are controlled using CS and the serial clock, allowing the devices to interface with microprocessors or DSPs. The input signal is sampled on the falling edge of CS and the conversion is also initiated at this point. There are no pipeline delays associated with the part.
The channel to be converted is selected through the DIN pin and the mode of operation is controlled by CS. The serial data stream from the DOUT pin has a channel identifier bit and a mode identifier bit, which provide information about the channel converted and the current mode of operation.
As a result of the Daisy Chain mode of operation, several AD7912/AD7922 can be connected together in Daisy Chain configuration. The Daisy Chain mode allows the user to read the conversion result from the ADCs contained in the chain.
The AD7912/AD7922 use advanced design techniques to achieve very low power dissipation at high throughput rates.
The reference for the part is taken internally from VDD. This allows the widest dynamic input range to the ADC. Thus the analog input range for the part is 0 to VDD. The conversion rate is determined by the SCLK signal.
AD7912/AD7922分别是10位和12位高速、低功耗、双通道、逐次逼近型ADC,采用2.35 V至5.25 V单电源供电,最高吞吐量达1 MSPS。这些器件内置一个低噪声、宽带宽采样/保持放大器,可处理6 MHz以上的输入频率。
转换过程和数据采集过程通过CS和串行时钟进行控制,从而为器件与微处理器或DSP接口创造了条件。输入信号在CS的下降沿进行采样,而转换同时在此处启动。该器件无流水线延迟。
通过DIN引脚选择需转换的通道,工作模式则由CS控制。DOUT引脚的串行数据流有一个通道识别位和一个模式识别位,可提供所转换通道和当前工作模式的相关信息。
由于采用菊花链工作模式,因此数个AD7912/AD7922器件可以通过菊花链配置形式连接起来。在菊花链模式下,用户可以从菊花链内的ADC中读取转换结果。
AD7912/AD7922采用先进的设计技术,可在高吞吐量的情况下实现极低的功耗。 rates.
基准电压从V DD获得,从而为ADC提供了最宽的动态输入范围,因此,其模拟输入范围为0至V DD。转换速率取决于SCLK信号。
| 产品型号 | 产品状态 | 封装 | 引脚 | 温度范围 |
|---|---|---|---|---|
| AD7922ARM | 量产 | 8 ld MSOP | 8 | 工业 |
| AD7922ARMZ | 量产 | 8 ld MSOP | 8 | 工业 |
| AD7922ARMZ-REEL | 量产 | 8 ld MSOP | 8 | 工业 |
| AD7922ARMZ-REEL7 | 量产 | 8 ld MSOP | 8 | 工业 |
| AD7922AUJZ-REEL7 | 量产 | 8 ld TSOT | 8 | 工业 |
| EVAL-AD7922CBZ | 量产 | 评估板 | - | 待定 |
