KOLLMORGEN-S20660-SRS- 特定输入通道的故障不会影响系统中的其它通道

Description

KOLLMORGEN-S20660-SRS- 特定输入通道的故障不会影响系统中的其它通道

KOLLMORGEN  科尔摩根 丹纳赫伺服驱动器  S20660-SRS S22460-SRS S20330-SRS S200系列
24位Σ-Δ型ADC集成可编程增益阵列(PGA)和基准电压源，为灵活地连接热电偶或RTD传感器提供完整的特性组合。

其特性包括片内基准电压源、可编程增益阵列、激励电流、偏置电压发生器以及提供增强50 Hz和60 Hz抑制选项的灵活滤波。 AD7124-4采用5 mm × 5 mm小型LFCSP封装，因而非常适合空间为重要考虑因素的通道间隔离设计。 它还包括多个可供用户使用的诊断功能。

ADuM5010隔离式DC/DC转换器通过集成的isoPower®技术提供3.3 V隔离电源。ADuM1441用于隔离AD7124-4的串行外设接口(SPI)。AD7124-4微功耗隔离器空闲时每通道的功耗仅4.8 μA，能效非常高。ADP2441是36 V降压DC-DC稳压器，采用工业标准24 V电源，具有宽输入电压容差。ADP2441用于将输入电压降至3.3 V，从而为所有控制器侧电路供电。
系统概述

通道间隔离在自动化系统中极具优势，因为特定输入通道的故障不会影响系统中的其它通道。 然而，通道间隔离输入模块给设计提出了重大挑战，具体表现在复杂度、空间限制和系统成本这些方面。

热电偶或RTD输入是工业自动化系统的常用输入，因此，设计一个能够处理两者的温度输入模块很有用。 这种灵活性最大程度地减少了两种输入模块的设计工作，而且为模块用户提供了灵活性。

AD7124-4显著降低了设计复杂度，提供一个片上系统，能够执行热电偶和RTD传感器所需的全部测量功能。

图1所示电路的每个通道大小仅有27 mm x 50 mm，若在印刷电路板(PCB)两面贴放器件，则上述面积可进一步缩小。 之所以能实现如此小的尺寸，是因为AD7124-4采用5 mm × 5 mm小型LFCSP封装，并且集成了几乎所有必需的功能，除了隔离以及附加前端滤波和保护之外。 用于数据和电源隔离的隔离电路仅占用87 mm2，最小合并宽度为12.5 mm。

KOLLMORGEN-S20660-SRS- 特定输入通道的故障不会影响系统中的其它通道

KOLLMORGEN Kollmorgen Kollmorgen Danaher servo drive S20660-SRS S22460-SRS S20330-SRS S200 series
The 24-bit sigma-δ ADC integrates a programmable gain array (PGA) and a voltage reference source to provide a complete set of characteristics for flexibly connecting thermocouples or RTD sensors.

Features include an on-chip reference voltage source, programmable gain array, excitation current, bias voltage generator, and flexible filtering that provides enhanced 50 Hz and 60 Hz rejection options. The AD7124-4 comes in a 5 mm × 5 mm small LFCSP package, making it ideal for channel isolation designs where space is an important consideration. It also includes several diagnostic functions available to users.

The ADuM5010 Isolated DC/DC converter provides 3.3V isolated power through integrated isoPower® technology. The ADuM1441 is used to isolate the serial peripheral interface (SPI) of the AD7124-4. The AD7124-4 micropower isolator consumes only 4.8 μA per channel when idle, making it extremely energy efficient. The ADP2441 is a 36 V buck DC-DC regulator with an industry standard 24 V supply and wide input voltage tolerance. The ADP2441 is used to reduce the input voltage to 3.3V, thus powering all controller side circuits.
System overview

Interchannel isolation is advantageous in automated systems because the failure of a particular input channel does not affect other channels in the system. However, isolating input modules between channels presents significant design challenges in terms of complexity, space constraints, and system cost.

Thermocouple or RTD inputs are commonly used in industrial automation systems, so it is useful to design a temperature input module that can handle both. This flexibility minimizes the design effort for both input modules and provides flexibility for module users.

The AD7124-4 significantly reduces design complexity and provides a system-on-chip capable of performing all the measurement functions required for thermocouple and RTD sensors.

Each channel size of the circuit shown in Figure 1 is only 27 mm x 50 mm, which can be further reduced by placing devices on both sides of the printed circuit board (PCB). Such a small size is possible because the AD7124-4 comes in a 5 mm x 5 mm small LFCSP package and integrates almost all the necessary features, except for isolation and additional front-end filtering and protection. The isolation circuit for data and power isolation occupies only 87 mm2 and has a minimum combined width of 12.5 mm.