原标题：Maxim MAX11044系列16位ADC三相功率测量方案

　　Maxim公司的MAX11044系列是16/14位4/6/8输入通路的模数转换器(ADC),具有单独的跟踪/保持电路(T/H)和SAR电路,每路的取样频率250ksps,T/H输入带宽4MHz,20MHz双向并行接口,主要用在自动测试设备,功率因素监测和修正,电网保护,多相马达控制以及震动和波形分析.本文介绍了MAX11044系列主要特性,框图,以及三相Petaluma (MAXREFDES30#)子系统参考设计框图,电路图,材料清单和PCB设计图.

　　The MAX11044/MAX11044B/MAX11045/MAX11045B/MAX11046/MAX11046B 16-bit and MAX11054/MAX11055/MAX11056 14-bit ADCs offer 4, 6, or 8 independent input channels. Featuring independent track and hold (T/H) and SAR circuitry, these parts provide simultaneous sampling at 250ksps for each channel.

　　The MAX11044/MAX11044B/MAX11045/MAX11045B/ MAX11046/MAX11046B and MAX11054/MAX11055/ MAX11056 accept a ±5V input. All inputs are overrange protected with internal ±20mA input clamps providing overrange protection with a simple external resistor. Other features include a 4MHz T/H input bandwidth, internal clock, and internal or external reference. A 20MHz, bidirectional, parallel interface provides the conversion results and accepts digital configuration inputs.

　　The MAX11044/MAX11044B/MAX11045/MAX11045B/MAX11046/MAX11046B and MAX11054/MAX11055/MAX11056 operate with a 4.75V to 5.25V analog supply and a separate flexible 2.7V to 5.25V digital supply for interfacing with the host without a level shifter. The MAX11044/MAX11044B/MAX11045/MAX11045B/MAX11046/MAX11046B are available in a 56-pin TQFN and 64-pinTQFP packages while the MAX11054/MAX11055/ MAX11056 are available in TQFP only and operate over the extended -40℃ to +85℃ temperature range.

　　MAX11044系列主要特性:

　　_ 16-Bit ADC (MAX11044/MAX11044B/MAX11045/MAX11045B/MAX11046/MAX11046B) and 14-Bit ADC (MAX11054/MAX11055/MAX11056)

　　8-Channel ADC (MAX11046/MAX11046B/MAX11056)

　　6-Channel ADC (MAX11045/MAX11045B/MAX11055)

　　4-Channel ADC (MAX11044/MAX11044B/MAX11054)

　　_ Single Analog and Digital Supply

　　_ High-Impedance Inputs Up to 1GΩ

　　_ On-Chip T/H Circuit for Each Channel

　　_ Fast 3μs Conversion Time

　　_ High Throughput: 250ksps for Each Channel

　　_ 16-Bit/14-Bit, High-Speed, Parallel Interface

　　_ Internal Clocked Conversions

　　_ 10ns Aperture Delay

　　_ 100ps Channel-to-Channel T/H Matching

　　_ Low Drift, Accurate 4.096V Internal Reference Providing an Input Range of ±5V

　　_ External Reference Range of 3.0V to 4.25V, Allowing Full-Scale Input Ranges of ±4.0V to ±5.2V

　　_ 56-Pin (8mm x 8mm) TQFN and 64-Pin (10mm x 10mm) TQFP Packages

　　_ Evaluation Kit Available

　　MAX11044系列应用:

　　Automatic Test Equipment

　　Power-Factor Monitoring and Correction

　　Power-Grid Protection

　　Multiphase Motor Control

　　Vibration and Waveform Analysis

　　图1. MAX11044系列功能框图

　　Petaluma (MAXREFDES30#)子系统参考设计

　　Three-phase power measurement applications require multiple analog inputs for voltage and current measurements on each line of the three-phase system. A power monitoring system must sample all of the analog inputs simultaneously to accurately calculate the instantaneous power consumption.

　　The Petaluma (MAXREFDES30#) subsystem reference design provides eight high-speed, 250ksps, 16-bit simultaneous-sampling analog input channels that accept ±10V input signals.

　　The Petaluma design utilizes two quadruple ultra-precision, ultra-low-noise input buffers (MAX44252); an 8-channel, 16-bit simultaneous-sampling ADC (MAX11046B); an ultra-high precision 4.096V voltage reference (MAX6126); and regulated +10V, -10V, and +5V power rails (MAX1659, MAX765/LM337, MAX8881). In addition to three-phase power measurement applications, this subsystem also performs well in any application that requires multiple simultaneous sampling of analog inputs, such as multiphase motor control and industrial vibration sensing.

　　图2. Petaluma (MAXREFDES30#)子系统外形图

　　图3. Petaluma (MAXREFDES30#)子系统框图

　　Petaluma (MAXREFDES30#)子系统主要特性和优势:

　　图4. Petaluma (MAXREFDES30#)子系统电路图(1)

　　图5. Petaluma (MAXREFDES30#)子系统电路图(2)

　　图6. Petaluma (MAXREFDES30#)子系统电路图(3)

　　图7. Petaluma (MAXREFDES30#)子系统电路图(4)

　　Petaluma (MAXREFDES30#)子系统材料清单: