ADI 公司的AD5791是單路20位電壓輸出數模轉換器(DAC),雙極工作電壓高達33V,正基準電壓從5V到VDD-2.5V,負基準電壓從VSS+2.5V到0V,精度1ppm,噪音頻譜密度7.5 nV/√Hz,溫度漂移0.05 ppm/°C,主要用在醫療儀器,測試測量,工業控制和高端科學和航空儀表.本文介紹了AD5791產品亮點和主要特性, 方框圖和菊花鏈接方框圖,以及典型應用電路圖和EVAL-AD5791評估板電路圖,材料清單和PCB元件布局圖.
The AD5791 is a single 20-bit, unbuffered voltage-output DAC that operates from a bipolar supply of up to 33 V. The AD5791 accepts a positive reference input in the range 5 V to VDD − 2.5 V and a negative reference input in the range VSS + 2.5 V to 0 V. The AD5791 offers a relative accuracy specification of ±1 LSB max, and operation is guaranteed monotonic with a ±1 LSB DNL maximum specification.
The part uses a versatile 3-wire serial interface that operates at clock rates up to 35 MHz and that is compatible with standard SPI, QSPI™, MICROWIRE™, and DSP interface standards. The part incorporates a power-on reset circuit that ensures the DAC output powers up to 0 V and 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.
AD5791產品亮點:
1 ppm Accuracy.
Wide Power Supply Range up to ±16.5 V.
Operating Temperature Range: −40℃ to +125℃.
Low 7.5 nV/√Hz Noise Spectral Density.
Low 0.05 ppm/℃ Temperature Drift.
AD5791主要特性:
1 ppm resolution
1 ppm INL
7.5 nV/√Hz noise spectral density
0.19 LSB long term linearity stability
<0.05 ppm/℃ temperature drift
1 μs settling time
1 nV-sec glitch impulse
Operating temperature range:−40℃ to +125℃
20-lead TSSOP package
Wide power supply range up to ±16.5 V
35 MHz Schmitt triggered digital interface
1.8 V compatible digital interface
AD5791應用:
Medical instrumentation
Test and measurement
Industrial control
High end scientific and aerospace instrumentation
圖1.AD5791方框圖
圖2.AD5791菊花鏈接方框圖
圖3.AD5791典型應用電路圖
EVAL-AD5791評估板
The EVAL-AD5791 is a full-featured evaluation board, designed to allow the user to easily evaluate all features of the AD5791 voltage output, 20-bit DAC. The AD5791 pins are accessible at on-board connectors for external connection. The board can be controlled by two means, via the on-board connector (J6) or via the system development platform connector (J3). The SDP board allows the evaluation board to be controlled through the USB port of a Windows® XP (SP2 or later) or Vista (32-bit) based PC using the AD5791 evaluation software.
EVAL-AD5791評估板主要特性:
Full-featured evaluation board for the AD5791
Link options
PC control in conjunction with Analog Devices, Inc., system development platform
PC software for control
圖4.EVAL-AD5791評估板連接框圖
EVALUATION BOARD SCHEMATICS AND ARTWORK
圖5.EVAL-AD5791評估板電路圖(1)
圖6.EVAL-AD5791評估板基準電壓電路圖
圖7.EVAL-AD5791評估板SDP板連接器電路
圖8.EVAL-AD5791評估板元件布局圖
EVAL-AD5791評估板材料清單(BOM):
詳情請見:
http://www.analog.com/static/imported-files/data_sheets/AD5791.pdf
和
http://www.analog.com/static/imported-files/user_guides/UG-185.pdf
