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TC620 TC621 5V, DUAL TRIP POINT TEMPERATURE SENSORS
FEATURES
s s s s User-Programmable Hysteresis and Temperature Set Point Easily Programs with 2 External Resistors Wide Temperature Detection Range ................ – 40°C to +125°C (TC620/621CVx) External Thermistor for Remote Sensing Applications (TC621x)
GENERAL DESCRIPTION
The TC620 and TC621 are programmable logic output temperature detectors designed for use in thermal management applications. The TC620 features an on-board temperature sensor, while the TC621 connects to an external NTC thermistor for remote sensing applications. Both devices feature dual thermal interrupt outputs (HIGH LIMIT and LOW LIMIT), each of which program with a single external resistor. On the TC620, these outputs are driven active (high) when measured temperature equals the user-programmed limits. The CONTROL (hysteresis) output is driven high when temperature equals the high limit setting, and returns low when temperature falls below the low limit setting. This output can be used to provide simple ON/OFF control to a cooling fan or heater. The TC621 provides the same output functions except that the logical states are inverted. The TC620/621 are usable over a maximum temperature range of – 40°C to +125°C. Ambient Temperature – 40°C to +85°C – 40°C to +85°C
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APPLICATIONS
s s s s Power Supply Overtemperature Detection Consumer Equipment Temperature Regulators CPU Thermal Protection
ORDERING INFORMATION
Part No. TC620x*COA TC620x*CPA TC620x*EOA TC620x*EPA TC620CVOA TC621x*COA TC621x*CPA Package Ambient Temperature
8-Pin SOIC 0°C to +70°C 8-Pin Plastic DIP 0°C to +70°C 8-Pin SOIC – 40°C to +85°C 8-Pin Plastic DIP – 40°C to +85°C 8-Pin SOIC – 40°C to +125°C 8-Pin SOIC 0°C to +70°C 8-Pin Plastic DIP 0°C to +70°C
Part No. TC621x*EOA TC621x*EPA
Package 8-Pin SOIC 8-Pin Plastic DIP
*The part code will be C or H (see Functional Block Diagram, below, and page 2).
FUNCTIONAL BLOCK DIAGRAM
VDD 8 Temp to Voltage Converter 1 Thermistor Interface Circuit 8 VDD
TC620
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THERMISTOR
TC621
4
+
2 LOW SET VREF GEN
7 LOW LIMIT HIGH SET 2 VREF GEN
+ –
7 HIGH LIMIT
–
VREF
VREF
+
HIGH SET 3 VREF GEN
6 HIGH LIMIT LOW SET R Q S Q 5 CONTROL* 3 VREF GEN
+ –
R Q S Q
6
LOW LIMIT
–
5 CONTROL*
*Suffix code "C" denotes cooling option (high true CONTROL output); suffix code "H" denotes heating option (low true CONTROL output).
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TC620/1-9 11/4/96
TELCOM SEMICONDUCTOR, INC.
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5V, DUAL TRIP POINT TEMPERATURE SENSORS TC620 TC621
ABSOLUTE MAXIMUM RATINGS*
Package Power Dissipation (TA ≤ 70°C) PDIP ............................................................... 730mW SOIC ............................................................... 470mW Derating Factors Plastic ............................................................8mW/°C Supply Voltage ............................................................20V Input Voltage Any Input ....... (GND – 0.3V) to (VDD +0.3V) Operating Temperature M Version ........