TC620HCOA

TC620/TC621 5V, Dual Trip Point Temperature Sensors Features Package Type • User Programmable Hysteresis and Temperature Set Point • Easily Programs with Two External Resistors • Wide Temperature Detection Range: - 0°C to 70°C: (TC620/TC621CCX) - -40°C to +125°C: (TC620/TC621CVX) - -40°C to +85°C: (TC620/TC621CEX) • Onboard Temperature Sensing Applications (TC620X) • External NTC Thermistor for Remote Sensing Applications (TC621X) • Available in 8-Pin PDIP and SOIC Packages 8-PDIP NC 1 LOW SET 2 HIGH SET 3 VDD 7 HIGH LIMIT 8 TC620XCPA TC620XEPA 6 LOW LIMIT 5 CONTROL GND 4 8-PDIP THERMISTOR 1 HIGH SET 2 LOW SET 3 VDD 7 HIGH LIMIT 8 TC621XCPA TC621XEPA 6 LOW LIMIT 5 CONTROL GND 4 8-SOIC Applications • • • • Power Supply Over Temperature Detection Consumer Equipment Temperature Regulators CPU Thermal Protection NC 1 8 VDD LOW SET 2 7 LOW LIMIT 5 CONTROL HIGH SET 3 GND 4 TC620XCOA TC620XEOA 6 HIGH LIMIT TC620CVOA 8-SOIC THERMISTOR 1 Device Selection Table HIGH SET 2 Part Number Package Temperature Range TC620X*COA 8-Pin SOIC 0°C to +70°C TC620X*CPA 8-Pin PDIP 0°C to +70°C TC620X*EOA 8-Pin SOIC -40°C to +85°C TC620X*EPA 8-Pin PDIP -40°C to +85°C TC620C*VOA 8-Pin SOIC -40°C to +125°C TC621X*COA 8-Pin SOIC 0°C to +70°C TC621X*CPA 8-Pin PDIP 0°C to +70°C TC621X*EOA 8-Pin SOIC -40°C to +85°C TC621X*EPA 8-Pin PDIP -40°C to +85°C TC621C*VOA 8-Pin SOIC -40°C to +125°C Note: *The part code will be C or H (see Functional Block Diagrams). VDD HIGH LIMIT 7 8 LOW SET 3 TC621XCOA TC621XEOA 6 LOW LIMIT GND 4 5 CONTROL General Description The TC620 and TC621 are programmable logic output temperature detectors designed for use in thermal management applications. The TC620 features an onboard 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 is programmed 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 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/TC621 are usable over operating temperature ranges of 0°C to 70°C, -40°C to +125°C.  2001-2015 Microchip Technology Inc. DS20001439E-page 1 TC620/TC621 Functional Block Diagrams VDD 8 Temp. to Voltage Converter 4 TC620 + 2 LOW SET VREF GEN 7 LOW LIMIT – VREF + HIGH SET 3 VREF GEN 6 HIGH LIMIT – R S Q Q 5 CONTROL* VDD 8 1 THERMISTOR Thermistor Interface Circuit 4 TC621 + HIGH SET 2 VREF GEN 7 HIGH LIMIT – VREF + LOW SET 3 VREF GEN 6 LOW LIMIT – R S Q Q 5 CONTROL* *Suffix code "C" denotes cooling option (High true CONTROL output). Suffix code "H" denotes heating option (Low true CONTROL output). DS20001439E-page 2  2001-2015 Microchip Technology Inc. TC620/TC621 1.0 ELECTRICAL CHARACTERISTICS *Stresses above those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only and functional operation of the device at these or any other conditions above those indicated in the operation sections of the specifications is not implied. Exposure to Absolute Maximum Rating conditions for extended periods may affect device reliability. Absolute Maximum Ratings* Supply Voltage ....................................................... 20V Input Voltage Any Input .. (GND – 0.3V) to (VDD +0.3V) Package Power Dissipation (TA  70°C) PDIP ............................................. 730 mW SOIC ............................................. 470 mW Derating Factors: Plastic .......................................... 8 mW/°C Operating Temperature: V Version ......................... -40°C to +125°C E Version ........................... -40°C to +85°C C Version .............................. 0°C to +70°C Storage Temperature ......................... -65°C to +150°C TC620/TC621 ELECTRICAL SPECIFICATIONS Electrical Characteristics: TA = 25°C, unless otherwise specified. Symbol Parameter Min. Typ. Max. Unit Test Conditions VDD Supply Voltage Range 4.5 — 18 V IDD Supply Current — 270 400 A 5V  VDD  18V ROUT Output Resistance — 400 1000 W Output High or Low, 5V  VDD  18V IOUT Output Current — — 1 mA Temp. Sensed Source/Sink IOUT Output Current — — 1 mA Cool/Heat Source/Sink TERR Absolute Accuracy T-3 T T+3 °C T = Programmed Temperature TEMPERATURE CHARACTERISTICS Electrical Specifications: Unless otherwise noted, all parameters apply with 4.5V  VDD  18V. Parameters Sym. Min. Typ. Max. Units Specified Temperature Range (C) TA 0 — +70 °C Specified Temperature Range (E) TA -40 — +85 °C Specified Temperature Range (V) TA -40 — +125 °C Conditions Temperature Ranges Maximum Junction Temperature TJ — — +150 °C Storage Temperature Range TA -65 — +150 °C Thermal Resistance, 8L-PDIP JA — 125 — °C/W Thermal Resistance, 8L-SOIC JA — 155 — °C/W Package Thermal Resistances  2001-2015 Microchip Technology Inc. DS20001439E-page 3 TC620/TC621 2.0 PIN DESCRIPTIONS The descriptions of the pins are listed in Table 2-1. TABLE 2-1: TC620 PIN FUNCTION TABLE Pin No. (8-Pin PDIP) (8-Pin SOIC) Symbol 1 NC 2 LOW SET Low temperature set point. Connect an external 1% resistor from LOW SET to VDD to set trip point. 3 HIGH SET High temperature set point. Connect an external 1% resistor from HIGH SET to VDD to set trip point. 4 GND Description No Internal Connection. Ground Terminal. 5 CONTROL Control output. 6 HIGH LIMIT High temperature push/pull output. 7 LOW LIMIT Low temperature push/pull output. 8 VDD TABLE 2-2: Power supply input. TC621 PIN FUNCTION TABLE Pin No. (8-Pin PDIP) (8-Pin SOIC) Symbol 1 THERMISTOR 2 HIGH SET High temperature set point. Connect an external 1% resistor from HIGH SET to VDD to set trip point. 3 LOW SET Low temperature set point. Connect an external 1% resistor from LOW SET to VDD to set trip point. 4 GND 5 CONTROL Control output. 6 LOW LIMIT Low temperature push/pull output. 7 HIGH LIMIT High temperature push/pull output. 8 VDD DS20001439E-page 4 Description Thermistor input. Ground Terminal. Power supply input.  2001-2015 Microchip Technology Inc. TC620/TC621 DETAILED DESCRIPTION The TC620 has a positive temperature coefficient temperature sensor and a dual threshold detector. Temperature set point programming is accomplished with external resistors from the HIGH SET and LOW SET inputs to VDD. The HIGH LIMIT and LOW LIMIT outputs remain low as long as measured temperature is below set point values. As measured temperature increases, the LOW LIMIT output is driven high when temperature equals the LOW SET set point (±3°C max). If temperature continues to climb, the HIGH LIMIT output is driven high when temperature equals the HIGH SET set point (Figure 3-1). The CONTROL (hysteresis) output is latched in its active state at the temperature specified by the HIGH SET resistor. CONTROL is maintained active until temperature falls to the value specified by the LOW SET resistor. Care must also be taken to ensure the LOW SET temperature setting is at least 5°C lower than the HIGH SET temperature setting. Figure 3-2 can help the user obtain an estimate of the external resistor values required for the desired LOW SET and HIGH SET trip points. 250 RESISTANCE, RTRIP (kΩ) 3.0 200 150 100 50 -55 -35 -15 5 25 45 65 85 105 125 TEMPERATURE (°C) High Set Point Temperature FIGURE 3-2: Trip Temperature. TC620 Sense Resistors vs. Low Set Point Low Limit Output 3.2 High Limit Output To prevent output “chattering” when measured temperature is at (or near) the programmed trip point values, the LOW SET and HIGH SET inputs each have built-in hysteresis of -2°C below the programmed settings (Figure 3-3). Control Output (Cool Option Control Output (Heat Option) FIGURE 3-1: Output Logic. 3.1 TC620/TC621 Input vs. Built-in Hysteresis Programming the TC620 The resistor values to achieve the desired trip point temperatures on HIGH SET and LOW SET are calculated using Equation 3-1: EQUATION 3-1: RTRIP = 0.5997 x T 2.1312 Set Point (Set Point 2°C) High Limit or Low Limit Output Where: RTRIP = Programming resistor in Ohms T = The desired trip point temperature in degrees Kelvin. For example, a 50°C setting on either the HIGH SET or LOW SET input is calculated using Equation 3-2 as follows: FIGURE 3-3: Built-In Hysteresis on Low Limit and High Limit Outputs. As shown, the outputs remain in their active state (hysteresis) until temperature falls an additional 2°C below the user’s setting. EQUATION 3-2: RSET = 0.5997 x ((50 + 273.15)2.1312) = 133.6 k Care must be taken to ensure the LOW SET programming resistor is a smaller value than the HIGH SET programming resistor. Failure to do this will result in erroneous operation of the CONTROL output.  2001-2015 Microchip Technology Inc. DS20001439E-page 5 TC620/TC621 Using the TC621 The TC621 operation is similar to that of the TC620, but requires an external NTC thermistor. Use the resistance versus temperature curve of the thermistor to determine the values of the programming resistors. Note that the pin numbers for the HIGH SET and LOW SET programming resistors for the TC621 are reversed versus that of the TC620 (i.e., the resistor value on HIGH SET [Pin 2] should always be lower than the one connected to LOW SET [Pin 3]). Also note that the outputs of the TC621 are LOW TRUE when used with an NTC thermistor. 350 300 THERMISTOR RESISTANCE (kΩ) 3.3 250 200 150 100 50 0 0 3.4 10 The TC621 uses an external thermistor to monitor the controlling temperature. A thermistor with a resistance value of approximately 100 k at 25°C is recommended. A temperature set point is selected by picking a resistor whose value is equal to the resistance of the thermistor at the desired temperature. For example, using the data shown in Figure 3-4, a 30 k resistor between HIGH TEMP (Pin 2) and VDD (Pin 8) sets the high temperature trip point at +51°C and a 49 k resistor on LOW TEMP (Pin 3) sets the low temperature trip point to +41°C. DS20001439E-page 6 20 30 40 50 60 70 TEMPERATURE (°C) TC621 Thermistor Selection FIGURE 3-4: 3.5 Typical NTC Thermistor. TC620/TC621 Outputs Both devices have complimentary output stages. They are rated at a source or sink current of 1 mA maximum.  2001-2015 Microchip Technology Inc. TC620/TC621 4.0 TYPICAL APPLICATIONS 4.1 Dual Speed Temperature Control 4.2 Temperature Controlled Fan In the application in Figure 4-2, a high and a low temperature is selected by two RL and RH. The TC620 monitors the ambient temperature and turns the FET switch on when the temperature exceeds the HIGH TEMP set point. The fan remains on until the temperature decreases to the LOW TEMP set point. This provides the hysteresis. In this application, the fan turns on only when required. In Figure 4-1, the Dual Speed Temperature Control uses a TC620 and a TC4469 quad driver. Two of the drivers of the TC4469 are configured in a simple oscillator. When the temperature is below the LOW TEMP set point, the output of the driver is OFF. When the temperature exceeds the LOW TEMP set point, the TC4469 gates the oscillator signal to the outputs of the driver. This square wave signal modulates the remaining outputs and drives the motor at a low speed. If this speed cannot keep the temperature below the HIGH TEMP set point, then the driver turns on continuously which increases the fan speed to high. The TC620 will monitor the temperature and only allow the fan to operate when needed and at the required speed to maintain the desired temperature. A higher power option can be designed by adding a resistor and a power MOSFET. The TC621 uses an external thermistor to monitor the ambient temperature. This adds one part, but allows more flexibility with the location of the temperature sensor. +12V 0.1 µF 2 3 High Temp. 1 5 50˚C High 6 1N4148 Limit TC620 Low 7 Limit Temperature Scale 1M 1N4148 1 µF Fan Motor 14 2 1 3 5 8 TC4469 4 0˚C – 30˚C (Fan Off) 30˚C – 50˚C (Fan Low) 50˚C – UP (Fan High) FIGURE 4-1: 10 µF 8 Low Temp. 30˚C VMOTOR 10k 13 4 6 9 10 11 12 100k 50 Ω MOSFET 50 pF Higher Power Option 7 Fan Motor Dual Speed Temperature Control. +12V +12V Thermistor (NTC) Low Temp. 1 RL 2 3 RH 4 High Temp. FIGURE 4-2: 8 TC620 Fan Motor 7 6 5 MTP3055E High Temp. 1 RH 3 Low Temp. RL 4 2 8 TC621 Fan Motor 7 6 5 MTP3055E Temperature Controlled Fan.  2001-2015 Microchip Technology Inc. DS20001439E-page 7 TC620/TC621 4.5V to 18V High Temp. Low Temp. 1 2 3 4 TC620 8 7 6 5 1 2 3 4 5 6 7 TC4469 14 13 12 11 10 9 8 1k 1k High Temp. Warning Low Temp. Warning Heating/Cooling Equipment FIGURE 4-3: DS20001439E-page 8 Heating and Cooling Application.  2001-2015 Microchip Technology Inc. TC620/TC621 5.0 PACKAGING INFORMATION 5.1 Package Marking Information 8-Lead PDIP (300 mil) XXXXXXXX XXXXXNNN YYWW Example TC620C CPA e^^3 256 1503 TC621C CPA ^^ e3256 1503 8-Lead SOIC (150 mil) Example TC620HC 3 1503 OA e^^ NNN 256 TC621HE OA e^^3 1503 256 Legend: XX...X Y YY WW NNN e3 * Note: Customer-specific information Year code (last digit of calendar year) Year code (last 2 digits of calendar year) Week code (week of January 1 is week ‘01’) Alphanumeric traceability code Pb-free JEDEC® designator for Matte Tin (Sn) This package is Pb-free. The Pb-free JEDEC designator ( e3 ) can be found on the outer packaging for this package. In the event the full Microchip part number cannot be marked on one line, it will be carried over to the next line, thus limiting the number of available characters for customer-specific information.  2001-2015 Microchip Technology Inc. DS20001439E-page 9 TC620/TC621          ! ;' *"'# ' < $."+  " " '  < &'' $' '' :==...* *= < N NOTE 1 E1 1 3 2 D E A2 A L A1 c e eB b1 b >'" * "A*'" ?#*, &" ?1@4 ? ? ?B C F '  ' '  G G  $ $<