ADI AD5780 18位精度低噪音±10 V DC电压源解决方案
发布时间:2012-1-18 12:10
发布者:1046235000
ADI公司的AD5780是真正18位线性低噪音精密的±10 V DC电压源,工作电压双极电压高达33V,采用正基准输入电压从5V到VDD-2.5V,而负基准输入电压从VSS+2.5V到0V,输出噪音8 nV/√Hz,长期稳定性为0.025 LSB,增益误差±0.018 ppm/℃,输出电压设定时间2.5 μs, 施密特触发器数字接口35MHz,1.8V兼容数字接口,主要用在医疗仪器,测试测量,工业控制,数据采集系统,数字增益和失调调整,电源控制等.本文介绍了AD57801产品亮点和主要特性, 功能框图和典型工作电路图以及评估板EVAL-AD5780主要特性,电路图,材料清单和PCB布局图. The AD57801 is a true 18-bit, unbuffered voltage output DAC that operates from a bipolar supply of up to 33 V. The AD5780 accepts a positive reference input range of 5 V to VDD − 2.5 V and a negative reference input range of VSS + 2.5 V to 0 V. Both reference inputs are buffered on chip and external buffers are not required. The AD5780 offers a relative accuracy specifica-tion of ±1 LSB maximum range, and operation is guaranteed monotonic with a ±1 LSB DNL maximum range specification. The part uses a versatile 3-wire serial interface that operates at clock rates of up to 35 MHz and is compatible with standard SPI, QSPI™, MICROWIRE™, and DSP interface standards. The part incorporates a power-on reset circuit that ensures that the DAC output powers up to 0 V in a known output impedance state and remains in this state until a valid write to the device takes place. The part provides an output clamp feature that places the output in a defined load state. AD57801产品亮点: True 18-bit accuracy. Wide power supply range of up to ±16.5 V. −40℃ to +125℃ operating temperature range. Low 8 nV/√Hz noise. Low ±0.018 ppm/℃ gain error temperature coefficient AD57801主要特性: True 18-bit voltage output DAC, ±1 LSB INL 8 nV/√Hz output noise spectral density 0.025 LSB long-term linearity error stability ±0.018 ppm/°C gain error temperature coefficient 2.5 μs output voltage settling time 3.5 nV-sec midscale glitch impulse Integrated precision reference buffers Operating temperature range: −40℃ to +125℃ 4 mm × 5 mm LFCSP package Wide power supply range of up to ±16.5 V 35 MHz Schmitt triggered digital interface 1.8 V-compatible digital interface AD57801应用: Medical instrumentation Test and measurement Industrial control Scientific and aerospace instrumentation Data acquisition systems Digital gain and offset adjustment Power supply control 图1.AD57801功能框图 图2.AD57801典型工作电路图 AD57801评估板EVAL-AD5780 Evaluation Board for a 18-Bit Serial Input, Voltage Output DAC with Integrated Precision Reference Buffer Amplifiers The EVAL-AD5780 is a full-featured evaluation board, designed to allow the user to easily evaluate all features of the AD5780 voltage output, 18-bit digital-to-analog converter (DAC). The AD5780 pins are accessible at on-board connectors for external connection. The board can be controlled by two means: via the on-board connector (J3), or via the system development platform connector (J4). The SDP board allows the evaluation board to be controlled through the USB port of a Windows® XP- (SP2 or later) or Vista-based (32-bit) PC using the AD5780 evaluation software. 评估板EVAL-AD5780主要特性: Full-featured evaluation board for the AD5780 Link options PC control in conjunction with Analog Devices, Inc., system development platform PC software for control 图3.评估板EVAL-AD5780框图 图4.评估板EVAL-AD5780电路图:AD5780 图5.评估板EVAL-AD5780电路图:电压参考电路 图6.评估板EVAL-AD5780电路图:SDP板连接器 图7. 18位精度±10V电压源简化电路图 评估板EVAL-AD5780材料清单: 图8.评估板EVAL-AD5780 PCB布局图 详情请见: |
网友评论