CN-122016072-A - Temperature sampling circuit, sampling method and vehicle

CN122016072ACN 122016072 ACN122016072 ACN 122016072ACN-122016072-A

Abstract

The invention discloses a temperature sampling circuit, a temperature sampling method and a vehicle, which comprise a main voltage dividing resistor, an auxiliary voltage dividing resistor, an NTC thermistor, a control switch, a power supply voltage node, a ground node, a sampling node, a control interface and a sampling interface, wherein the power supply voltage node is respectively connected with one end of the main voltage dividing resistor and one end of the switch side of the control switch, the control end of the control switch is connected with the control interface, the control interface is connected with the control module, the other end of the switch side of the control switch is connected with one end of the auxiliary voltage dividing resistor, the other end of the main voltage dividing resistor is respectively connected with one end of the NTC thermistor, the other end of the auxiliary voltage dividing resistor and the sampling node, the sampling node is connected with the acquisition module through the sampling interface, and the other end of the NTC thermistor is connected with the ground node. The invention uses the control switch to control the mode of connecting and not connecting the auxiliary voltage dividing resistor, so that the measurement temperature of the whole sampling is wider and the result is more reliable. Is used in the technical field of vehicles.

Inventors

ZHOU XIAOZHU
GAO HANG
ZHAO XIAOXUE
YU TENG
LV JIAWEN
LI ZE
YANG XIAOKE

Assignees

中国第一汽车股份有限公司

Dates

Publication Date: 20260512
Application Date: 20251212

Claims (10)

1. The temperature sampling circuit is characterized by comprising a main voltage dividing resistor, an auxiliary voltage dividing resistor, an NTC thermistor, a control switch, a power supply voltage node, a ground node, a sampling node, a control interface and a sampling interface; The control end of the control switch is connected with a control interface, and the control interface is connected with an external control module; The other end of the switch side of the control switch is connected with one end of an auxiliary voltage dividing resistor, the other end of the main voltage dividing resistor is respectively connected with one end of an NTC thermistor, the other end of the auxiliary voltage dividing resistor and a sampling node, the sampling node is connected with an external acquisition module through the sampling interface, and the other end of the NTC thermistor is connected with a node to ground.
2. The temperature sampling circuit of claim 1, further comprising an oscillation-suppressing resistor connected in series between a control terminal of the control switch and the control interface.
3. The temperature sampling circuit of claim 1, further comprising a current limiting resistor connected in series between the sampling node and the sampling interface.
4. The temperature sampling circuit of claim 1, further comprising a first filter capacitor, wherein one end of the first filter capacitor is connected to the sampling node, and the other end of the first filter capacitor is connected to the ground node.
5. The temperature sampling circuit of claim 1, further comprising a second filter capacitor, wherein one end of the second filter capacitor is connected to the sampling interface, and the other end of the second filter capacitor is connected to the node to ground.
6. The temperature sampling circuit according to claim 1, wherein the control switch is an NMOS transistor, a gate of the NMOS transistor is connected to the control interface, a source of the NMOS transistor is connected to the supply voltage node, and a drain of the NMOS transistor is connected to one end of the auxiliary voltage dividing resistor.
7. The temperature sampling circuit of claim 4, wherein the first filter capacitor has a value on the order of nanofarads.
8. The temperature sampling circuit of claim 5, wherein the second filter capacitor has a value on the order of nanofarads.
9. A temperature sampling method is characterized in that the temperature sampling method is applied to the temperature sampling circuit of any one of claims 1 to 8, and comprises the steps of conducting a control switch when the current temperature is determined to be in a set high temperature interval, so that an auxiliary voltage dividing resistor is connected; When the current temperature is determined to be in the set low temperature interval, the control switch is turned off to disconnect the auxiliary voltage dividing resistor, and after the auxiliary voltage dividing resistor is determined to disconnect the auxiliary voltage dividing resistor, temperature data are collected through the sampling node.
10. A vehicle, characterized in that it is integrated with a temperature sampling circuit according to any one of claims 1 to 8.

Description

Temperature sampling circuit, sampling method and vehicle Technical Field The invention relates to the technical field of vehicles, in particular to a temperature sampling circuit, a sampling method and a vehicle. Background In the related art, the NTC thermistor is widely used for temperature measurement due to its low cost and fast response speed. However, the resistance of the NTC thermistor exhibits a nonlinear relationship with temperature, so that the whole measurement system is limited in terms of wide range and high-precision measurement. In the existing temperature sampling circuit, a voltage divider is generally formed by connecting a fixed voltage dividing resistor and an NTC thermistor in series, and sampling is performed at a voltage dividing point. Through researches, the circuit mode has the advantages that the acquisition precision obtained in different temperature intervals is different, so that the whole measured temperature interval is limited if certain precision is kept. Therefore, how to increase the measurement range of the whole sampling circuit and maintain the stability of the measurement accuracy is a technical problem that needs to be studied in the industry. Disclosure of Invention The invention provides a temperature sampling circuit, a sampling method and a vehicle, which are used for solving the problems of improving the measurement range of the whole sampling circuit and keeping the stability of measurement precision, and at least providing a beneficial selection or creation condition. The invention provides a temperature sampling circuit which comprises a main voltage dividing resistor, an auxiliary voltage dividing resistor, an NTC thermistor, a control switch, a power supply voltage node, a grounding node, a sampling node, a control interface and a sampling interface, wherein the main voltage dividing resistor is connected with the NTC thermistor; The control end of the control switch is connected with a control interface, and the control interface is connected with an external control module; The other end of the switch side of the control switch is connected with one end of an auxiliary voltage dividing resistor, the other end of the main voltage dividing resistor is respectively connected with one end of an NTC thermistor, the other end of the auxiliary voltage dividing resistor and a sampling node, the sampling node is connected with an external acquisition module through the sampling interface, and the other end of the NTC thermistor is connected with a node to ground. Further, the temperature sampling circuit further comprises an oscillation suppression resistor, and the oscillation suppression resistor is connected in series between the control end of the control switch and the control interface. Further, the temperature sampling circuit further comprises a current limiting resistor, and the current limiting resistor is connected between the sampling node and the sampling interface in series. Further, the temperature sampling circuit further comprises a first filter capacitor, one end of the first filter capacitor is connected with the sampling node, and the other end of the first filter capacitor is connected with the ground node. Further, the temperature sampling circuit further comprises a second filter capacitor, one end of the second filter capacitor is connected with the sampling interface, and the other end of the second filter capacitor is connected with the ground node. Further, the control switch is an NMOS tube, the grid electrode of the NMOS tube is connected with the control interface, the source electrode of the NMOS tube is connected with the power supply voltage node, and the drain electrode of the NMOS tube is connected with one end of the auxiliary voltage dividing resistor. Further, the value of the first filter capacitor is in the nano-meter level. Further, the value of the second filter capacitor is in the nano-meter level. On the other hand, the temperature sampling method is applied to the temperature sampling circuit in any one of the technical schemes, and comprises the steps of conducting a control switch when the current temperature is determined to be in a set high temperature interval, enabling an auxiliary voltage dividing resistor to be connected; When the current temperature is determined to be in the set low temperature interval, the control switch is turned off to disconnect the auxiliary voltage dividing resistor, and after the auxiliary voltage dividing resistor is determined to disconnect the auxiliary voltage dividing resistor, temperature data are collected through the sampling node. In another aspect, a vehicle is provided, which integrates a temperature sampling circuit according to any one of the above technical solutions. The circuit has the advantages that the auxiliary voltage dividing resistor and the control switch are added, and the control switch is used for controlling the mode of connecting the auxiliary voltage di