This is a temperature control circuit that is controlled by fan. This circuit is built by TC620. This circuit is very simple form. This is the figure of the circuit.
The circuit in the figure above will turn on the fan at +45°C and give an over-temperature warning at +85°C. The entire circuit operates from a single +5V power supply, so the over-temperature warning is CMOS/TTL compatible. Also, supply current is only about 140 μA when the fan is off, which makes the circuit ideal for battery-powered equipment. As previously mentioned, semiconductor thermal sensor is offer low and repeatable hysteresis when compared with bimetallic devices. Low hysteresis is very important in protecting critical electronic systems that must be restarted as soon as possible, such as a file server. Since the system will normally attempt a restart operation as soon as the temperature returns to an acceptable level, minimum hysteresis equates to minimum time before the system can return to service. [Schematic circuit source: Microchip Technology, Inc].
The circuit in the figure above will turn on the fan at +45°C and give an over-temperature warning at +85°C. The entire circuit operates from a single +5V power supply, so the over-temperature warning is CMOS/TTL compatible. Also, supply current is only about 140 μA when the fan is off, which makes the circuit ideal for battery-powered equipment. As previously mentioned, semiconductor thermal sensor is offer low and repeatable hysteresis when compared with bimetallic devices. Low hysteresis is very important in protecting critical electronic systems that must be restarted as soon as possible, such as a file server. Since the system will normally attempt a restart operation as soon as the temperature returns to an acceptable level, minimum hysteresis equates to minimum time before the system can return to service. [Schematic circuit source: Microchip Technology, Inc].
0 comments:
Post a Comment