NTC thermistor produced by EXSENSE Electronics Technology Co., Ltd. is made of ceramic technology based on metal oxides such as manganese, cobalt, nickel and copper, etc.. These metal oxide materials have semiconductor properties, so when the NTC thermistor is at low temperature, a low number of carriers (electrons and holes) of these oxide materials at low temperatures, so their resistance values are higher; And as the temperature increases, the number of carriers increases, so the resistance value decreases. This characteristic make NTC thermistor widely used in the temperature monitoring of medical equipment, such as monitor, syringe pump.
Syringe pump should be used as an aid when the clinical drugs must be injected intravenously, and where the dose must be very accurate, the total amount is small, the speed of dose is slow or constant for a long time. During operation, the actual internal temperature will accumulate at the actual ambient temperature and behave differently at different ambient temperatures. The internal devices of the syringe pump have corresponding temperature requirements, and many failure modes are closely related to the temperature parameters. At present, in most cases, the use of the syringe pump room temperature as the actual use of the internal device temperature, that is, there is no-temperature monitoring system of syringe pump.
Today, EXSENSE Electronics introduce a temperature monitoring system of syringe pump, which can collect records of the internal temperature and humidity of the sealed syringe pump and upload it to the terminal through the communication method supported by the syringe pump, and its statistical data can be collected by the manufacturers of syringe pump to analyze the actual ambient temperature of their internal devices. This temperature monitoring system of syringe pump includes NTC thermistors, 8-chosen-1 analog switch, microprocessor, memory and PC terminal. Among them, NTC thermistors includes the SMD type NTC thermistor located near the temperature-sensitive point of the temperature-sensitive component and the epoxy resin coating NTC thermistor located on the surface of the temperature-sensitive component. Temperature-sensitive components connected to SMD type NTC thermistor include sound drive chips, microprocessor, motor-driven chips, and the temperature-sensitive components connected with epoxy resin coating NTC includes power modules, power supply battery, and motor.
This temperature monitoring system of syringe pump, the SMD type NTC thermistor is installed directly on the circuit board near the corresponding temperature-measured point, such as sound drive chip, motor drive chip, microprocessor, etc.; While the epoxy resin coating NTC thermistor is installed on the surface of the temperature-measured components with heat-conducting insulation paste, such as power supply module, power supply battery, motors, etc. With the change of ambient temperature and the operating temperature of the syringe pump itself, the actual operating temperature of each temperature-sensitive part surface will change, and the resistance value of the corresponding NTC thermistor will change accordingly. The data acquisition circuit converts the amount of temperature change into the amount of voltage change, the microprocessor of the system selects the 8-chosen-1 analog switch in turn through the relevant chip selection instructions, reads the voltage values of each temperature measurement point in order, and stores the data in the external memory after AD conversion. After the measurement is completed, through the wired communication interface or the wireless WIFI module in the syringe pump, the data collected during the measurement is stored in the database of the PC terminal application program. The collected data can be analyzed and processed by the application program and the data processing results and temperature acquisition curves are obtained at the same time, thus a temperature monitoring system for temperature-sensitive devices inside the syringe pump is realized.
