ADIAD578018位精度低噪音±10VDC電壓源解決方案

ADI公司的AD5780是真正18位線性低噪音精密的±10 V DC電壓源,工作電壓雙極電壓高達(dá)33V,采用正基準(zhǔn)輸入電壓從5V到VDD-2.5V,而負(fù)基準(zhǔn)輸入電壓從VSS+2.5V到0V,輸出噪音8 nV/√Hz,長期穩(wěn)定性為0.025 LSB,增益誤差±0.018 ppm/℃,輸出電壓設(shè)定時間2.5 μs, 施密特觸發(fā)器數(shù)字接口35MHz,1.8V兼容數(shù)字接口,主要用在醫(yī)療儀器,測試測量,工業(yè)控制,數(shù)據(jù)采集系統(tǒng),數(shù)字增益和失調(diào)調(diào)整,電源控制等.本文介紹了AD57801產(chǎn)品亮點和主要特性, 功能框圖和典型工作電路圖以及評估板EVAL-AD5780主要特性,電路圖,材料清單和PCB布局圖.

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產(chǎn)品亮點:

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應(yīng)用:

Medical instrumentation

Test and measurement

Industrial control

Scientific and aerospace instrumentation

Data acquisition systems

Digital gain and offset adjustment

Power supply control

圖1.AD57801功能框圖

圖2.AD57801典型工作電路圖

AD57801評估板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.

評估板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

圖3.評估板EVAL-AD5780框圖

圖4.評估板EVAL-AD5780電路圖:AD5780

圖5.評估板EVAL-AD5780電路圖:電壓參考電路

圖6.評估板EVAL-AD5780電路圖:SDP板連接器

圖7. 18位精度±10V電壓源簡化電路圖
評估板EVAL-AD5780材料清單:




圖8.評估板EVAL-AD5780 PCB布局圖
詳情請見:
http://www.analog.com/static/imported-files/data_sheets/AD5780.pdf
和
http://www.analog.com/static/imported-files/user_guides/UG-256.pdf

電路圖符號相關(guān)文章:電路圖符號大全