TC646BEOA Microchip Technology, TC646BEOA Datasheet

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... GND 4 5 2003 Microchip Technology Inc. Description The TC646B/TC648B/TC649B devices are new ver- sions of the existing TC646/TC648/TC649 fan speed controllers. These devices are switch-mode fan speed controllers that incorporate a new fan auto-restart func- tion. Temperature-proportional speed control is accom- plished using pulse width modulation. A thermistor (or ...

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... Clock F Generator SHDN GND DS21755B-page 2 V OTF V Note DD Note: The V Control is for the TC646B device only. Logic 3xT PWM V OUT Timer Start-up Timer FAULT Missing Pulse Detect SENSE (typ Control Logic V OUT Start-up Timer OTF NC comparator OTF 2003 Microchip Technology Inc. ...

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... V IN Shutdown Mode Hysteresis SHDN REL HYST Input Leakage Note 1: Ensured by design, tested during characterization. 2: For V < 3.7V, t and t DD STARTUP 2003 Microchip Technology Inc. TC646B/TC648B/TC649B PIN FUNCTION TABLE Name +0.3V GND SENSE/NC FAULT/OTF V OUT V DD Min Typ Max 3.0 — ...

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... JA — 155 JA — 125 JA < +85° 3.0V to 5.5V Units Conditions 1.0 µ µsec 2 sec TC646B and TC649B, Note 2 sec Note 2 sec TC646B and TC649B Units Conditions °C °C °C — °C/W — °C/W — °C/W 2003 Microchip Technology Inc. ...

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... TC646B/TC648B/TC649B Start-up Timing. 33.3 msec ( µ OUT FAULT SENSE FIGURE 1-2: Fan Fault Occurrence (TC646B and TC649B). V OUT FAULT Minimum 16 pulses SENSE FIGURE 1-3: Recovery From Fan Fault (TC646B and TC649B). 2003 Microchip Technology Inc. TC646B/TC648B/TC649B t DIAG (TC646B and TC649B) DS21755B-page 5 ...

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... OUT TC646B TC648B TC649B K 6 FAULT / OTF 5 SENSE GND are adjusted to get the necessary 1 µF value Current 0.1 µF + limited - voltage source Current + limited - voltage source SENSE (pulse voltage source) TC646B and TC649B 2003 Microchip Technology Inc. ...

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... 3. 100 200 300 400 500 (mV FIGURE 2-3: PWM Source Current (I vs 2003 Microchip Technology Inc. TC646B/TC648B/TC649B = 5V 25°C. A 30.50 30.00 29.50 29.00 28. 110 125 -40 -25 -10 FIGURE 2-4: Temperature. 170 Pins 6 & 7 Open 165 C F 160 155 = 4.0V 150 145 140 135 ...

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... FIGURE 2-12: vs. Temperature 110 125 Temperature (ºC) Sense Threshold ) vs. Temperature 100 150 200 250 300 350 400 V (mV) OL FAULT / OTF 110 125 Temperature (ºC) PWM Source Current (I OH 2003 Microchip Technology Inc. ) ...

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... DD 0.75 0. 4.0V 0.65 DD 0.60 0.55 0. 3.0V DD 0.45 0.40 -40 -25 - Temperature (ºC) FIGURE 2-15: V Threshold vs. REL Temperature. 2003 Microchip Technology Inc. TC646B/TC648B/TC649B = 5V 25°C. A 2.630 2.625 2.620 V = 5.0V DD 2.615 2.610 2.605 2.600 2.595 95 110 125 -40 -25 -10 ) vs. FIGURE 2-16: OL Temperature. 100 ...

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... Power Supply Input (V The V pin with respect to GND provides power to the DD device. This bias supply voltage may be independent of the fan power supply. 3.8 Ground (GND) Ground terminal. 3.9 No Connect (NC) No internal connection. voltage reaches OUT output is continuously on. OUT ) DD 2003 Microchip Technology Inc. ...

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... Using a standard 2N2222A NPN transistor DS(on) (assuming a Vce-sat of 0.8V), the power dissipation would (Iavg* Vce-sat). 2003 Microchip Technology Inc. TC646B/TC648B/TC649B The PWM approach to fan speed control results in much less power dissipation in the drive element. This allows smaller devices to be used and will not require special heatsinking to remove the power being dissipated in the package ...

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... The duty cycle of the PWM IN IN pin. When the voltage F pin is 2.60V, the PWM duty cycle IN ” and CMIN ”. A calcu- CMAX and V is character- CMIN CMAX “ and has a typical value of 1.4V, with PWM DUTY CYCLE ( 100 IN CMIN CMAX CMIN 2003 Microchip Technology Inc. ...

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... MOSFET. The V output is designed to be able to quickly raise the OUT base current or the gate voltage of the external drive device to its final value. 2003 Microchip Technology Inc. TC646B/TC648B/TC649B When the device is in shutdown/auto-shutdown mode, IN and the V output is actively held low ...

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... DC fan motors, illustrated in Figures 4-6 and 4-7. output is OUT FIGURE 4-6: And Positive Commutation Current. inputs. AS level during = 0V). If OUT thresh- REL pin IN FIGURE 4-7: Commutation Pulses To Zero. Fan Current With DC Offset Fan Current With 2003 Microchip Technology Inc. ...

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... SENSE pin input. This stops the TC646B/TC649B device from falsely sensing a current pulse that is due to the fan drive device turn-on. 2003 Microchip Technology Inc. TC646B/TC648B/TC649B The initial pulse blanker is also implemented to stop false sensing of fan current pulses. When a fan ...

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... V IN REL? Yes Auto Yes Shutdown OUT Power-Up V > HAS Yes Yes Hot Start TC646B Only No M.P.D. Yes Fire Diagnostic Timer (100 msec) No Fire Start-up Yes Fan Pulse Timer Detected? (1 sec) Yes Fan Pulse Detected? No Fan Fault 2003 Microchip Technology Inc. ...

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... Yes Minimum Speed Mode No Yes Auto- V < Shutdown OUT No Yes OUT No V > 1.20V IN Yes Power-Up Yes OTF = 0 FIGURE 4-10: TC648B Behavioral Algorithm. 2003 Microchip Technology Inc. TC646B/TC648B/TC649B = 0 Shutdown V > HAS Yes Fire Start-up Timer (1 sec) Normal Operation Minimum Speed Mode > 1.20V ...

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... DIV Temperature Sensing is a conventional NTC thermistor, T and R form the temperature decreases and the value of T input. R helps to linear voltages over the desired tem desired, a larger value DD pin IN volt --------------------------------------------- - R TEMP --------------------------------------------- - R TEMP and the 2003 Microchip Technology Inc. ...

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... Sensor Scientific ™ - U.S. Sensor - Vishay - Advanced Thermal - muRata ™ Products 2003 Microchip Technology Inc. TC646B/TC648B/TC649B 5.4 FanSense Network (R SENSE The SENSE network (comprised allows the TC646B and TC649B devices to SENSE detect commutation of the fan motor. R the fan current into a voltage. C voltage signal to the SENSE pin ...

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... Due to the pulse mode opera- tion, the actual RMS current of the fan is very near the 220 mA rating. Because of this, the power rating for the R resistor does not have to be oversized for this SENSE application. ® , 12V, 220 mA fan. 2003 Microchip Technology Inc. ...

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... MOSFET to go into avalanche mode. Since there is very little energy in this occurrence, it will probably not fail the device, but it would be a long-term reliability issue. 2003 Microchip Technology Inc. TC646B/TC648B/TC649B The following is recommended: • Ask how the fan is designed. If the fan has clamp diodes internally, this problem will not be seen ...

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... The system bias voltage to run the fan controller is 5V, while the fan voltage is 12V. Fan Bias FAN SENSE GND Fan Current Suggested DS (mA) Rbase ( ) 150 800 150 800 500 301 500 Note 1 500 Note 1 1000 Note 1 500 Note 1 @ 25ºC, Thermometrics 2003 Microchip Technology Inc. ® ...

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... This information will help in the selection of the R and C values later on. Also of interest for the SENSE R selection value is what the fan current does in SENSE a locked-rotor condition. 2003 Microchip Technology Inc. TC646B/TC648B/TC649B ® ® , Panaflo - FIGURE 5-9: Fan Current. From Figure 5- seen that in a locked-rotor fault condition, the fan goes into a pulsed current mode of operation ...

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... Using standard 1% resistor values yields the following values 32 17 and 1 voltage, thermistor resistance and IN versus temperature for this 5.00 4.50 4. 3.50 3.00 2.50 2.00 NTC Thermistor 1.50 100 k @ 25ºC 1.00 0.50 0. Temperature (ºC) Thermistor Resistance vs. Temperature ). AS and DIV 2003 Microchip Technology Inc. 3 ...

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... Figures 5-11 (4.7 ) and 5-12 (3.0 ). The selected C value is 0.1 µF, as this provides the SENSE appropriate coupling of the voltage to the SENSE pin. FIGURE 5-11: SENSE pin voltage with 4.7 sense resistor. 2003 Microchip Technology Inc. TC646B/TC648B/TC649B ). 1 Values. FIGURE 5-12: 3.0 sense resistor. Since the 3.0 ...

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... FAULT output. The value for this resistor is system-dependent. DS21755B-page VDD ® 1.0 µ FAULT 7 TC649B V OUT SENSE C F GND were also B is the pull-up 5 +12V ® Panasonic Fan 12V, 140 mA 5 FBA06T12H Q 1 SI2302 or MGSF1N02E C SENSE R 0.1 µF SENSE 3.0 2003 Microchip Technology Inc. ...

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... 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. * Standard device marking consists of Microchip part number, year code, week code, and traceability code. 2003 Microchip Technology Inc. TC646B/TC648B/TC649B : Example TC646BCPA 025 ...

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... MILLIMETERS MIN NOM MAX 8 2.54 3.56 3.94 4.32 2.92 3.30 3.68 0.38 7.62 7.94 8.26 6.10 6.35 6.60 9.14 9.46 9.78 3.18 3.30 3.43 0.20 0.29 0.38 1.14 1.46 1.78 0.36 0.46 0.56 7.87 9.40 10. 2003 Microchip Technology Inc. ...

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... Mold Draft Angle Top Mold Draft Angle Bottom * Controlling Parameter § Significant Characteristic Notes: Dimensions D and E1 do not include mold flash or protrusions. Mold flash or protrusions shall not exceed .010” (0.254mm) per side. JEDEC Equivalent: MS-012 Drawing No. C04-057 2003 Microchip Technology Inc. TC646B/TC648B/TC649B ...

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... A2 MILLIMETERS* MIN NOM MAX 8 0.65 BSC - - 1.10 0.75 0.85 0.95 0.00 - 0.15 4.90 BSC 3.00 BSC 3.00 BSC 0.40 0.60 0.80 0.95 REF 8° 0° - 8° 0.08 - 0.23 0.22 - 0.40 5° - 15° 5° - 15° 2003 Microchip Technology Inc. ...

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... Component Taping Orientation for 8-Pin SOIC Devices PIN 1 Carrier Tape, Number of Components Per Reel and Reel Size: Package Carrier Width (W) 8-Pin SOIC 12 mm 2003 Microchip Technology Inc. TC646B/TC648B/TC649B User Direction of Feed W P Standard Reel Component Orientation for 713 or TR Suffix Device ...

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... TC646B/TC648B/TC649B NOTES: DS21755B-page 32 2003 Microchip Technology Inc. ...

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... Customer Notification System Register on our web site (www.microchip.com/cn) to receive the most current information on our products. 2003 Microchip Technology Inc. TC646B/TC648B/TC649B . Examples: a) TC646BEOA: SOIC package. b) TC646BEOA713: Tape and Reel, SOIC package. c) TC646BEPA: PDIP package. d) TC646BEUA: MSOP package. a) TC648BEOA: SOIC package. b) TC648BEPA: PDIP package. ...

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... TC646B/TC648B/TC649B NOTES: DS21755B-page 34 2003 Microchip Technology Inc. ...

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... Serialized Quick Turn Programming (SQTP service mark of Microchip Technology Incorporated in the U.S.A. All other trademarks mentioned herein are property of their respective companies. © 2003, Microchip Technology Incorporated, Printed in the U.S.A., All Rights Reserved. Printed on recycled paper. Microchip received QS-9000 quality system ...

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... Korea Microchip Technology Korea 168-1, Youngbo Bldg. 3 Floor Samsung-Dong, Kangnam-Ku Seoul, Korea 135-882 Tel: 82-2-554-7200 Fax: 82-2-558-5934 Singapore Microchip Technology Singapore Pte Ltd. 200 Middle Road #07-02 Prime Centre Singapore, 188980 Tel: 65-6334-8870 Fax: 65-6334-8850 Taiwan Microchip Technology (Barbados) Inc., Taiwan Branch 11F-3, No ...