A temperature control device for a single-resistance micro-hot plate

Abstract

The invention relates to a temperature control device, in particular to a temperature control device applied to a single resistance micro hot plate, comprising a test current circuit and a heating current circuit. The temperature control device applied to the single resistance micro hot plate has the following advantages: (1) the test current circuit with an adaptive adjustment function is designed, and for different target operating temperatures, the circuit can automatically switch to the appropriate test current to reduce the temperature fluctuation range, thus achieving high-precision temperature control; (2) a clock generation circuit with a microsecond level period is designed, the internal integration of the clock signal circuit is realized, and high integration is realized; and (3)a heating mode control circuit is designed, which can realize switch between a continuous heating mode and a gap heating mode through a heating mode control signal, and can control the heating cycleand duty ratio of the gap heating mode, so as to achieve low power consumption.

Description

technical field [0001] The invention relates to a temperature control device, in particular to a temperature control device for a single-resistance micro-hot plate. Background technique [0002] In the micro hot plate sensor, in order to improve the integration and reduce the cost, the only resistor (single resistor) is often designed. When the current passes through this resistance, heat energy is generated due to the Joule heating effect to increase the temperature of the micro-hot plate; at the same time, this resistance also has a stable temperature resistance coefficient, and its resistance value increases or decreases monotonously with the change of temperature. By measuring the resistance value to obtain the average temperature of the micro-hotplate. Most of the existing temperature control circuits are only applicable to the situation where the heating device and the temperature measuring device are separated, such as the authorized invention patent "Accurate Temper...

AI Technical Summary

Problems solved by technology

The problem is that due to the use of a fixed test current, if it is necessary to achieve temperature control in the lower temperature zone, the test current must be small enough, resulting in a lower upper limit temperature of the micro-hot plate and poor temperature control accuracy in the high temperature zone; For precise temperature control in the high-temperature zone, the test current must be large enough to cause the lower limit temperature that the micro-hot plate can reach to be too high

Therefore, the circuit with a single test current has the problems of narrow temperature control range and poor temperature control accuracy.

In addition, in the published relevant literature, most of the clock pulse signals are externally connected, and internal integration has not yet been seen.

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