AD22105 Datasheet | Analog Devices

FEATURES User-programmable temperature setpoint ±2.0°C maximum ambient setpoint accuracy 4.1°C typical hysteresis Wide supply range: 2.7 V to 7.0 V Wide temperature range: - 40°C to +150°C Low power dissipation APPLICATIONS Industrial process control Thermal control systems CPU monitoring puter thermal management circuits Fan control Handheld/portable electronic equipment GENERAL DESCRIPTION The AD22105 is a solid state thermostatic switch. Requiring only one external programming resistor, the AD22105 can be set to switch accurately at any temperature in the - 40°C to +150°C wide operating range. Using a novel circuit architecture, the AD22105 asserts an open-collector output when the ambient temperature exceeds the user-programmed setpoint temperature. The AD22105 has approximately 4°C of hysteresis, which prevents rapid thermal on and off cycling. The AD22105 operates on a single power supply voltage from 2.7 V to 7.0 V, facilitating operation in battery-powered applications as well as in industrial control systems. Because of low power dissipation (230 µW at 3.3 V), self heating errors are minimized, and battery life is maximized. An optional internal 200 kΩ pull-up resistor is included to facilitate driving light loads such as plementary metal- oxide semiconductor (CMOS) inputs. Alternatively, a low power light emitting diode (LED) indicator can be driven directly. FUNCTIONAL BLOCK DIAGRAM RPULL- UP 1 200kΩ 8 NC OUT 2 GND 3 NC 4 SETPOINT TEMPERATURE SENSOR 7 VS 6 RSET 5 NC Figure 1. Rev. A Document Feedback Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibilityisassumedby Analog Devices for itsuse,nor foranyinfringementsofpatentsor other rights of third parties that may result from its use. Specifications subject to change without notice. No license is granted by implication or otherwise under any patent or patent rights of Analog Devices. Trademarksandregisteredtrademarksarethepropertyoftheir...