Thermoelectric cooler ( TEC ) has two functions: heating and cooling, depending on the direction of input current. It has been widely used in medical, industry, military and some other fields needing to be cooled. 1. Reducing the thickness of the thermal insulating layer The main method to reduce heat transfer temperature is to decrease the thickness of the thermal insulating layer. Take 12704 type thermopile made of alumina ceramics as an example. If its thickness is reduced from 0.8mm to 0.5mm...(more)
2.Weld resistance As each of thermoelectric elements weld thermal couple, there are 4 places in the TEC needing to be welded, so there are 4 weld resistances. The weld resistance includes solder resistance and contact resistance. The solder resistance is proportional to the thickness of the solder, and the contact resistance is related to the size error of galvanic elements and welding process. If the size error is big, more solder will fill between the short component and the metal film, so it ...(more)
The principle of thermoelectric cooler ( TEC ) is solid thermoelectric effect. Comparing with other cooling methods, TEC has obviously different cooling effect. This cooling method takes electrons as energy carrier, and because of no need of refrigerant, there is no environmental pollution problem. TEC has no moving parts besides fan, so it has simple structure, small noise, high reliability, long service lifetime and some other advantages. Most of TECs are made of N type and P type thermocouple...(more)
Most of high precision constant current sources use integrated operational amplifier. The principle is to make the voltages added to the two input ports of the comparison amplifier are equal by using negative influence, resulting in constant current output there are two factors that affect the stability of the output constant from the constant current sources: one is the inner factor of the constant current source, like voltage reference, sampling resistor, amplifier gain, zero drift, and noise ...(more)
This article continues to introduce TEC loss mechanism. (2) Heat conduction loss In cooling process, heat conduction mainly plays a role of heat change. The pathway of heat conduction is that the cold side absorbs the heat of heat load, which can be transferred to heat sink, so the cold side thermoregulation can be realized. The cooling capacity can directly affect TEC cooling efficiency. Whats more, the size and the cooling method of heat sink are also important factors to affect the cooling ef...(more)
Figure 1 is the schematic diagram of thermoelectric cooler (TEC). TEC is made up of N-type semiconductor, P-type semiconductor, cold pate, hot plate and wires. Figure 1. Schematic diagram of TEC In working process, TEC continuously absorbs heat from the cold side and release heat from the hot side. TEC has many advantages, such as no moving parts, no refrigerant, no pollution, no noise, high reliability, long service lifetime and so on. However, it also has some disadvantages. Its biggest weakne...(more)
Thermistors are thermal elements made of semiconductor materials. Resistance value of thermistors can vary with the temperature of resistor bodies. Thermistors can be divided into three types: positive temperature coefficient thermistor (PTC), negative temperature coefficient thermistor (NTC) and critical temperature coefficient thermistor (CRT). NTC thermistor has the following advantages: (1)High sensitivity The absolute value of its temperature coefficient resistance is greater than that of t...(more)
A low DC voltage is added on the both sides of thermoelectric cooler ( TEC ) and heat will flow from one side of the component to the other side. At this time, the temperature on one side of TEC will decrease and the temperature on the other side will increase. It is noteworthy that as long as the current direction is changed, the heat flow direction can be changed. So a TEC can realize two functions, cooling and heating at the same time. TEC can be used for precise temperature control. Whats mo...(more)
