TC648B Microchip Technology Inc., TC648B Datasheet
TC648B
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TC648B Summary of contents
Page 1
... Even with the FAULT output low, the V output is on full during the fan fault condition in order to attempt to restart the fan. FAULT (TC646B) or OTF (TC648B) is also asserted if the PWM reaches 100% duty cycle, indicating that maximum cooling capability has been reached and a possible overheating condition exists ...
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... TC646B/TC648B/TC649B Functional Block Diagram TC646B/TC649B Clock F Generator SHDN GND TC648B V OTF 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 ...
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... 1.0 — +1.0 IN timers are typically 13/f. MP Function Analog Input Analog Output Analog Input Ground Analog Input. No Connect (NC) for TC648B Digital (Open-Drain) Output OTF for TC648B Digital Output Power Supply Input < +85° 3.0V to 5.5V Units Conditions V µA Pins 6, 7 Open µF, V ...
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... TC646B/TC648B/TC649B ELECTRICAL CHARACTERISTICS (CONTINUED) Electrical Specifications: Unless otherwise specified, all limits are specified for -40°C < T Parameters Sym Pulse-Width Modulator PWM Frequency f PWM SENSE Input (TC646B & TC649B) SENSE Input Threshold Voltage V TH(SENSE) with Respect to GND Blanking time to ignore pulse due ...
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... TIMING SPECIFICATIONS t STARTUP V OUT FAULT / OTF SENSE FIGURE 1-1: 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. ...
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... 0.1 µ .01 µF 0.1 µF 1 µF Note: C and C 5 FIGURE 1-4: TC646B/TC648B/TC649B Electrical Characteristics Test Circuit. DS21755B-page µF 0.1 µ OUT TC646B TC648B TC649B K 6 FAULT / OTF 5 SENSE GND are adjusted to get the necessary 1 µ ...
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... 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 ...
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... TC646B/TC648B/TC649B Note: Unless otherwise indicated -40 -25 - Temperature (ºC) FIGURE 2-7: FAULT / OTF V Temperature. 2.610 V = 5.5V DD 2.600 2.590 V = 3.0V DD 2.580 µF F 2.570 -40 -25 - Temperature (ºC) FIGURE 2-8: V vs. Temperature. ...
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... V = 5.0V 0.80 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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... TC649B devices), the output will remain low until the mode when fan fault condition has been removed (16 pulses have been detected at the SENSE pin in a 32/f period). For the TC646B and TC648B devices, the FAULT/OTF out- put will also be asserted when the V the V threshold of 2.62V (typical). This gives an OTF over-temperature/100% fan speed indication 3 ...
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... The duty cycle can be varied from 100%. The pulse train generated by the TC646B/ TC648B/TC649B device drives the gate of an external N-channel MOSFET or the base of an NPN transistor. (shown in Figure 4-2). See Section 5.5, “Output Drive Device Selection”, for more information on output drive device selection ...
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... As the duty cycle on is decreased (pulse on time “t ” is lowered), the fan on will slow down proportionally. With the TC646B, TC648B and TC649B devices, the duty cycle is con- trolled by the V input and can also be terminated by IN the V input (auto-shutdown). This is described in AS more detail in Section 5.5, “ ...
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... For the TC646B, TC648B and TC649B devices, the V pin is also used as the shutdown pin. The V V threshold voltages are characterized in the “Elec- REL trical Characteristics Table” of Section 1.0. If the V voltage is pulled below the V threshold, the device SHDN will shut down (V output goes to a low state, the OUT FAULT/OTF pin is inactive) ...
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... Sensing Fan Operation (SENSE) input reaches IN The SENSE input is an analog input used to monitor the fan’s operation (the TC648B device does not incor- threshold and porate the fan sensing feature). It does this by sensing fan current pulses that represent fan rotation. When a fan rotates, commutation of the fan current occurs as the fan poles pass the armatures of the motor ...
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... Behavioral Algorithms The behavioral algorithms for the TC646B/TC649B and TC648B devices are shown in Figure 4-9 and FAN Figure 4-10, respectively. The behavioral algorithms show the step-by-step deci- sion-making process for the fan speed controller oper- ation ...
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... TC646B/TC648B/TC649B Power-Up Power-on Reset FAULT = 1 Yes Shutdown V < SHDN OUT No Yes Auto- V < Shutdown OUT Hot Start Fire Start-up Timer (1 sec) Fire Start-up Timer Fan Pulse No (1 sec) Detected? Yes Yes Fan Pulse Detected? Normal No Operation ...
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... 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 ...
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... A very important factor to consider when selecting the PWM frequency for the TC646B/TC648B/TC649B devices is the RPM rating of the selected fan and the minimum duty cycle that you will be operating at. For fans that have a full-speed rating of 3000 RPM or less desirable to use a lower PWM frequency ...
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... 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. The goal of the SENSE network is to provide a voltage pulse to the SENSE pin that has a minimum amplitude ...
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... TC646B/TC648B/TC649B TABLE 5-1: FAN CURRENT VS. R Nominal Fan Current R SENSE (mA) 50 100 150 200 250 300 350 400 450 500 The values listed in Table 5-1 are for fans that have the fan current waveshape shown in Figure 4-7. With this waveshape, the average fan current is closer to the peak value, which requires the resistor value to be higher ...
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... FIGURE 5-5: Fan Current During a Locked Rotor Condition. 5.5 Output Drive Device Selection The TC646B/TC648B/TC649B is designed to drive an external NPN transistor or N-channel MOSFET as the fan speed modulating element. These two arrange- ments are shown in Figure 5-7. For lower-current fans, NPN transistors are a very economical choice for the fan drive device ...
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... For this reason, the V pin should be bypassed with a IN 0.01 µF capacitor. In order to keep fan noise off of the TC646B/TC648B/ TC649B device ground, individual ground returns for the TC646B/TC648B/TC649B and the low side of the fan current sense resistor should be used. DS21755B-page 22 ...
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... 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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... TC646B/TC648B/TC649B Step 2: Selecting the Fan Controller. The requirements for the fan controller are that it have auto-shutdown capability at 20ºC and also indicate a fan fault condition. No over-temperature indication is necessary. From these specifications, the proper selection is the TC649B device. Step 3: Setting the PWM Frequency. ...
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... 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 value of sense resistor provides the proper voltage to the SENSE pin the correct choice ...
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... TC646B/TC648B/TC649B +5V R Thermometrics 1 100 k @25°C 237 k NHQ104B425R5 0.01 µ 45. 0.01 µ 17 1.0 µF FIGURE 5-13: Design Example Schematic. Bypass capacitor C is added to the design to VDD decouple the bias voltage. This is good to have, espe- cially when using a MOSFET as the drive device. This ...
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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 0215 : ...
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... TC646B/TC648B/TC649B 8-Lead Plastic Dual In-line (PA) – 300 mil (PDIP Dimension Limits Number of Pins Pitch Top to Seating Plane Molded Package Thickness Base to Seating Plane Shoulder to Shoulder Width Molded Package Width Overall Length Tip to Seating Plane Lead Thickness Upper Lead Width ...
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... 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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... TC646B/TC648B/TC649B 8-Lead Plastic Micro Small Outline Package (UA) (MSOP (F) β Dimension Limits Number of Pins Pitch Overall Height Molded Package Thickness Standoff Overall Width Molded Package Width Overall Length Foot Length Footprint (Reference) Foot Angle Lead Thickness Lead Width Mold Draft Angle Top ...
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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 Pitch (P) Part Per Full Reel ...
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... TC646B/TC648B/TC649B NOTES: DS21755B-page 32 2003 Microchip Technology Inc. ...
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... Range Device: TC646B: PWM Fan Speed Controller with Fan Restart, Auto-Shutdown, Fan Fault and Over-Temp Detection TC648B: PWM Fan Speed Controller with Auto- Shutdown and Over-Temp Detection TC649B: PWM Fan Speed Controller with Fan Restart, Auto-Shutdown and Fan Fault Detection Temperature E = -40° ...
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... TC646B/TC648B/TC649B NOTES: DS21755B-page 34 2003 Microchip Technology Inc. ...
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... QS-9000 compliant for its PICmicro 8-bit MCUs code hopping ® ® devices, Serial EEPROMs, microperipherals, non-volatile memory and analog products. In addition, Microchip’s quality system for the design and manufacture of development systems is ISO 9001 certified. 2003 Microchip Technology Inc ...
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... D-85737 Ismaning, Germany Tel: 49-89-627-144-0 Fax: 49-89-627-144-44 Italy Microchip Technology SRL Via Quasimodo, 12 20025 Legnano (MI) Milan, Italy Tel: 39-0331-742611 Fax: 39-0331-466781 United Kingdom Microchip Ltd. 505 Eskdale Road Winnersh Triangle Wokingham Berkshire, England RG41 5TU Tel: 44-118-921-5869 Fax: 44-118-921-5820 03/25/03 2003 Microchip Technology Inc. ...