Multi-channel temperature measuring device and multi-channel temperature measuring circuit thereof

Abstract

The invention discloses a multi-channel temperature measuring device and a multi-channel temperature measuring circuit used by the same, and the multi-channel temperature measuring device employs a plurality of resistive temperature measuring elements to cooperate with the multi-channel temperature measuring circuit to measure temperature. The temperature measuring elements adopt a four-wire system connection method, so that the influence of lead resistance on the temperature measuring precision is eliminated; wires led out from the two ends of at least two temperature measuring elements are connected with the same acquisition channel of a voltage measurer, a gating switch is used for controlling signals, acquired by the voltage measurer, of the temperature measuring elements, the multiplexing of the acquisition channel of the voltage measurer is achieved, the usage amount of the acquisition channel of the voltage measurer is saved, the complexity and the cost of the temperature measuring circuit are reduced; a signal relay is used as the gating switch, so that the leakage current of the gating switch is eliminated; the multi-channel temperature measuring device and wires, connectors, the gating switch and the like in the multi-channel temperature measuring circuit are arranged in a matched mode, wire impedance, inter-wire crosstalk, environmental electromagnetic interference and interference noise signals introduced by the thermoelectric effect are reduced, and the temperature measuring precision is improved.

Description

technical field [0001] The invention belongs to the technical field of temperature measurement, and relates to a multi-channel temperature measuring device and a multi-channel temperature measuring circuit. Background technique [0002] High-precision temperature measurement devices are often required in the advanced manufacturing field. For example, in the lithography equipment in the semiconductor manufacturing field, many positions require the temperature to be controlled within the range of 20-24°C, and the temperature fluctuation over time is required not to exceed 0.05°C; in order to meet the temperature control accuracy requirements, the temperature measuring device as one of the temperature feedback control components needs to have excellent measurement accuracy, usually requiring the measurement accuracy of the temperature measuring device to be better than 0.01°C or even 0.001°C. To achieve high-precision temperature measurement, the temperature measuring element i...

AI Technical Summary

Problems solved by technology

Generally, one port of the voltage measuring device is connected to a temperature measuring resistor; however, when the number of temperature measuring resistors is large, the number of channels of the voltage measuring device may be large, which will increase the cost of the system, especially for high-precision In terms of the temperature measuring device, the increase in the number of channels of the voltage measuring device will significantly increase the complexity and cost of the system

In addition, in a high-precision temperature measurement device, in addition to the precision of the RTD itself as a temperature measurement element will affect the temperature measurement accuracy, factors such as the resistance of the wires of the temperature measurement circuit, impedance matching, signal crosstalk, and pyroelectric effects will also affect the measurement accuracy. Temperature accuracy; especially when the temperature measurement accuracy is better than 0.01°C, the accuracy of the temperature measurement circuit has a significant impact on the temperature measurement accuracy

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