TC646 Microchip, TC646 Datasheet
TC646
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TC646 Summary of contents
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... See Section 5.0, “Typical Applications”, for more information and system design guidelines. The TC646 is available in the 8-pin plastic DIP, SOIC and MSOP packages and is available in the industrial and extended commercial temperature ranges. V ...
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... Functional Block Diagram – – SHDN GND DS21446C-page – OTF OTF – PWM + Control Logic PWM Timer Clock Generator Start-up Timer SHDN Missing Pulse Detect. TC646 + – 10k 70mV (typ OUT FAULT SENSE 2002 Microchip Technology Inc. ...
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... TC646 Units Test Conditions V mA Pins 6, 7 Open µ C(MAX) µA Pins 6, 7 Open; Note µ 0.35V F IN µA Note 1 µsec mA, Note 1 OH µ ...
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... TC646 DC ELECTRICAL SPECIFICATIONS (CONTINUED) Electrical Characteristics: Unless otherwise specified, T Symbol Parameter Inputs Voltage at V for 100% Duty C(MAX), OTF IN Cycle and Overtemp. Fault C(SPAN) C(MAX) C(MIN) V Auto-shutdown Threshold AS V Voltage Applied SHDN IN ensure Reset/Shutdown V Voltage Applied to V ...
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... The TC646 enters shut- OUT down mode when During shutdown, the IN SHDN FAULT output is inactive, and supply current falls to 25 µA (typical). The TC646 exits shutdown mode when V V (see Section 5.0, “Typical IN REL Applications”, for details). 2.2 Analog Output (C ...
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... The second condition by which the TC646 asserts a FAULT is when the PWM control voltage applied to V becomes greater than that needed to drive 100% duty cycle (see Section 1.0, “Electrical Characteristics”). ...
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... IN IN Figure 3-1). In this mode, all functions cease and the FAULT output is unconditionally inactive. The TC646 should not be shut down unless all heat producing activity in the system negligible level. The TC646 exits shutdown mode when V becomes greater than the release voltage. ...
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... Quit Normal Operation and go to Fan Fault. (10) End. DS21446C-page 8 4.3 Fan Fault Fan fault is an infinite loop wherein the TC646 is latched in shutdown mode. This mode can only be released by a reset (i.e then above (V SHDN ...
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... IN SHDN OUT Yes Yes No V > > REL IN AS HAS No Yes Power-Up FIGURE 4-1: TC646 Behavioral Algorithm Flowchart. 2002 Microchip Technology Inc. Normal Operation Clear Missing Pulse Detector V IN < SHDN V > REL No Yes V < Yes > ...
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... The TC642EV is a larger board intended for benchtop development and analysis. At the very least, anyone contemplating a design using the TC646 should consult the documen- tation for both TC642EV (DS21403) and TC642DEMO (DS21401). Figure 5-1 shows the base schematic for the TC642DEMO ...
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... V node added benefit, this IN configuration produces an output voltage delta of 1.4V, which is well within the range of the V specification of the TC646. A 100 k NTC thermistor is selected for this application in order to keep I minimum. For the voltage range equal to 1.25V to IN 2.65V, the temperature range of this configuration is 0° ...
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... Operations at Low Duty Cycle One boundary condition which may impact the selec- tion of the minimum fan speed is the irregular activation of the Diagnostic Timer due to the TC646 “missing” fan commutation pulses at low speeds. This is a natural consequence of low PWM duty cycles (typically 25% or less) ...
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... TABLE 5-1: Nominal Fan Current (mA SENSE 5.5 Output Drive Transistor Selection The TC646 is designed to drive an external transistor or MOSFET for modulating power to the fan. This is shown The V pin has a minimum source current OUT and a minimum sink current of 1 mA. Bipolar transistors or MOSFETs may be used as the power switching element, as shown in Figure 5-7 ...
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... TC646 A base-current limiting resistor is required with bipolar transistors. This is shown in Figure 5-6. R BASE – BASE + V BE (SAT SENSE FIGURE 5-6: Circuit For Determining R . BASE V DD Fan R BASE V OUT SENSE GND a) Single Bipolar Transistor FIGURE 5-7: Output Drive Transistor Circuit Topologies. ...
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... DD In addition, the V sup- 1 µF capacitor. Grounds should be kept as short as DD possible. To keep fan noise off the TC646 ground pin, individual ground returns for the TC646 and the low side of the fan current sense resistor should be used. TC646 Fan Q ...
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... Output codes 001[B] to 111[B] operate the fan from roughly 40% to 100% of full speed. An open-drain output from the processor (I/O0) can be used to reset the TC646 following detection of a fault condition. The FAULT out- put can be connected to the controller's interrupt input another I/O pin, for polled operation ...
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... + +5V . vs. Temperature RELEASE V = 3.0V DD 25˚C TEMPERATURE TC646 +12V +5V Fan 800 OUT 2N2222A TC646 + FAULT 0 SENSE GND R 11 2.2 85˚C DS21446C-page 17 ...
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... Standard marking consists of Microchip part number, year code, week code, traceability code (facility code, mask rev#, and assembly code). For marking beyond this, certain price adders apply. Please check with your Microchip Sales Office. DS21446C-page 18 Example: TC646VPA 025 0215 Example: TC646VOA 0215 025 Example: TC646E 215025 2002 Microchip Technology Inc. ...
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... A2 .115 .130 .145 A1 .015 E .300 .313 .325 E1 .240 .250 .260 D .360 .373 .385 L .125 .130 .135 c .008 .012 .015 B1 .045 .058 .070 B .014 .018 .022 § eB .310 .370 .430 TC646 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. ...
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... TC646 8-Lead Plastic Small Outline (SN) – Narrow, 150 mil (SOIC 45× c Dimension Limits Number of Pins Pitch Overall Height Molded Package Thickness Standoff § Overall Width Molded Package Width Overall Length Chamfer Distance Foot Length Foot Angle Lead Thickness ...
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... MAX .026 A .044 A2 .030 .034 .038 A1 .002 .006 E .193 .200 .184 .114 .118 .122 E1 D .114 .118 .122 L .016 .022 .028 F .035 .037 .039 .004 .006 .008 B .010 .012 .016 7 7 TC646 A2 MILLIMETERS* MIN NOM MAX 8 0.65 1.18 0.76 0.86 0.97 0.05 0.15 4.90 .5.08 4.67 2.90 3.00 3.10 2.90 3.00 3.10 0.40 0.55 0.70 0.90 0.95 1. 0.10 0.15 0.20 0.25 0.30 0. DS21446C-page 21 ...
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... TC646 6.2 Taping Form Component Taping Orientation for 8-Pin MSOP Devices PIN 1 Carrier Tape, Number of Components Per Reel and Reel Size Package 8-Pin MSOP Component Taping Orientation for 8-Pin SOIC (Narrow) Devices PIN 1 Carrier Tape, Number of Components Per Reel and Reel Size ...
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... Microchip's development systems software products. Plus, this line provides information on how customers ® ® can receive the most current upgrade kits.The Hot Line or Microsoft Numbers are: 1-800-755-2345 for U.S. and most of Canada, and 1-480-792-7302 for the rest of the world. TC646 092002 DS21446C-page23 ...
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... Telephone: (_______) _________ - _________ Application (optional): Would you like a reply? Y Device: TC646 Questions: 1. What are the best features of this document? 2. How does this document meet your hardware and software development needs you find the organization of this document easy to follow? If not, why? 4 ...
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... Auto Shutdown and Fault Detection, SOIC package. b) TC646VUA: PWM Fan Speed Controller w/ Auto Shutdown and Fault Detection, MSOP package. c) TC646VPA: PWM Fan Speed Controller w/ Auto Shutdown and Fault Detection, PDIP package. d) TC646EOA713: PWM Fan Speed Controller w/Auto Shutdown and Fault Detection, SOIC package, Tape and Reel ...
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... TC646 NOTES: DS21446C-page 26 2002 Microchip Technology Inc. ...
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... Microchip Technology Incorporated with respect to the accuracy or use of such information, or infringement of patents or other intellectual property rights arising from such use or otherwise. Use of Microchip’s products as critical com- ponents in life support systems is not authorized except with express written approval by Microchip. No licenses are con- veyed, implicitly or otherwise, under any intellectual property rights ...
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... Mississauga, Ontario L4V 1X5, Canada Tel: 905-673-0699 Fax: 905-673-6509 DS21446C-page ALES AND ERVICE ASIA/PACIFIC Australia Microchip Technology Australia Pty Ltd Suite 22, 41 Rawson Street Epping 2121, NSW Australia Tel: 61-2-9868-6733 Fax: 61-2-9868-6755 China - Beijing Microchip Technology Consulting (Shanghai) Co., Ltd., Beijing Liaison Office Unit 915 Bei Hai Wan Tai Bldg ...