TC655 Microchip Technology Inc., TC655 Datasheet
TC655
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TC655 Summary of contents
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... F2F (bit 1<0>) in the Status Register will also be set to a ‘1’. An over-temperature condition is indicated when the voltage at V TC655 devices indicate this by setting OTF(bit 5<X>) in the Status Register to a '1'. The TC655 device also pulls the FAULT line low during an over-temperature condition ...
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... TC654/TC655 Functional Block Diagram MIN SCLK SDA GND Note: OTF condition applies for the TC655 device only. DS21734A-page 2 TC654/TC655 – Note V OTF – + OTF + Control + Logic – Start-up Timer Missing Pulse Detect Clock Generator 50 k – Serial Port 100 mV (typ.) ...
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... I -1.0 — +1 100 120 THSENSE V — — 0 — 2.4 — FAULT -15 — + TC654/TC655 Function = 3 5 Units Conditions V µA Pins Open µA Pins Open µsec mA, Note 1 OH µsec mA, Note 10 80 ...
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... TC654/TC655 ELECTRICAL SPECIFICATIONS (CONTINUED) Electrical Characteristics: Unless otherwise noted, all limits are specified for V -40°C <T < +85°C. A Parameters 2-Wire Serial Bus Interface Logic Input High Logic Input Low Logic Output Low Input Capacitance SDA, SCLK I/O Leakage Current SDA Output Low Current Note 1: Not production tested, ensured by design, tested during characterization. 2: For 5.0 V > ...
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... G = MSB of Data Clocked into Slave H = LSB of Data Clocked into Slave I = Slave Pulls SDA Line Low Slave Pulls SDA Line Low F = Acknowledge Bit Clocked into Master G = MSB of Data Clocked into Master H = LSB of Data Clocked into Master TC654/TC655 SU(STOP) IDLE ...
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... TC654/TC655 2.0 TYPICAL PERFORMANCE CURVES Note: The graphs and tables provided following this note are a statistical summary based on a limited number of samples and are provided for informational purposes only. The performance characteristics listed herein are not tested or guaranteed. In some graphs or tables, the data presented may be outside the specified operating range (e ...
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... 110 125 -40 -25 FIGURE 2-11 Hysteresis vs. Temperature. THSENSE 150 140 130 V = 5.0 V 120 DD 110 100 110 125 -40 -25 FIGURE 2-12: Temperature. TC654/TC655 C = 1.0 µ 110 125 Temperature (ºC) RPM %error vs 3. ...
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... Digital (Open Drain) Output (FAULT) When the fan’s RPM falls below the user-set RPM threshold (or OTF occurs with TC655), a logic low sig- nal is asserted. DS21734A-page 8 3.6 Analog Input (SENSE2) Fan current pulses are detected at this pin. These pulses are counted and used in the calculation of the fan2 RPM ...
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... TC654/TC655 controls fan speed according to the sys- tem temperature.The goal of temperature proportional fan speed control is to reduce fan power consumption, increase fan life and reduce system acoustic noise. With the TC654 and TC655 devices, fan speed can be controlled by the analog input V or the SMBus inter- IN face, allowing for high system flexibility ...
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... D = Duty Cycle D = Ton / T FIGURE 4-2: Waveform. The TC654 and TC655 generate a pulse train with a typical frequency can be varied from 30% to 100%. The pulse train gen- erated by the TC654/TC655 devices drives the gate of an external N-channel MOSFET or the base of an NPN transistor (Figure 4-3) ...
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... Once the one second period is over, the F TC654/TC655 devices will look to see if SMBus or V control has been selected in the Configuration Register (DUTYC bit 5<0>). Based on this register, the device will choose which input will control the V Duty cycle control based the default state ...
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... OUT to control the PWM duty cycle via the SMBus, DUTYC (bit 5<0>) of the Configuration Register (Register 6.3) must be set to a ‘1’. This tells the TC654/TC655 device that the duty cycle should be controlled by the Duty Cycle Register. Next, the Duty Cycle Register must be programmed to the desired value ...
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... When the TC654/TC655 devices are in shutdown mode, all functions except for the SMBus interface are suspended. During this mode of operation, the TC654 and TC655 devices will draw a typical supply current of only 5 µA. Normal operation will resume as soon as Bit 0 in the Configuration Register is reset to ‘0’. ...
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... TC654/TC655 devices very flexible and easy to use. All of the available registers are detailed in Section 6.0. 4.11 SMBus Slave Address The slave address of the TC654/TC655 is 0011 011 and is fixed. This address is different from industry- standard digital temperature sensors (like TCN75) and, therefore, allow the TC654/TC655 to be utilized in sys- tems in conjunction with these components ...
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... TC654/TC655. The 7-bit SMBus address for the TC654/TC655 is 0011 011. The 7-bit address transmitted in the serial bit stream must match for the TC654/TC655 to respond with an Acknowledge (indicating the TC654/TC655 is on the bus and ready to accept data). The eighth bit in the Address Byte is a Read-Write Bit. This bit is a ‘ ...
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... In this case, the slave (TC654/TC655) will leave the data line HIGH to enable the master device to generate the STOP condition. ...
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... REGISTER SET The TC654/TC655 devices contain 9 registers that pro- vide a variety of data and functionality control to the outside system. These registers are listed below in TABLE 6-1: COMMAND BYTE ASSIGNMENTS Register Command RPM1 0000 0000 RPM2 0000 0001 FAN_FAULT1 0000 0010 FAN_FAULT2 0000 0011 ...
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... TC654/TC655 6.2 FAN_FAULT1 & FAN_FAULT2 Threshold Registers (FAN_FAULT1 & FAN_ FAULT2) The Fan Fault Threshold Registers (FAN_FAULT1 and FAN_ FAULT2) are used to set the fan fault threshold levels for fan 1 and fan 2, respectively. The Fan Fault Registers are 8-bit, read/writable registers that allow the fan fault RPM threshold to be set in 50 RPM incre- ments ...
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... F2PPR: Fan 2 Pulses Per Rotation The TC654/TC655 device uses this setting to understand how many current pulses per revolu- tion Fan 2 should have. It then uses this as part of the calculation for the fan 2 RPM value in the RPM2 Register. See Section 7.7 for application information on determining your fan’s number of current pulses per revolution ...
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... Unimplemented: Read as ‘0’ bit 5 OTF: Over Temperature Fault Condition For the TC654/TC655 device, this bit is set to the proper state immediately at startup and is therefore treated as an unknown (X cycle on V OUT bit will be set to ‘0’. This is determined at power-up. ...
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... See Register 6-6 for the Microchip manu- facturer ID. method of duty REGISTER 6-6: D[7] D[ 6.7 Version ID Register (VER_ID) This register is used to indicate which version of the device is being used, either the TC654 or the TC655. This register is a simple 2-bit Read only register. IN REGISTER 6-7: D[1] D[0] Version TC654/TC655 MANUFACTURER’ ...
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... Figure 7-1. Although SMBus specifications only require the SDA and SCLK lines to pull down 350 µA, with a maximum voltage drop of 0.4 V, the TC654/TC655 has been designed to meet a maximum voltage drop of 0.4 V, with current. This allows lower values of pull- up resistors to be used, which will allow higher bus capacitance ...
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... They are R described earlier, you can see that the thermistor has a logarithmic resistance variation. When put in parallel with R , though, the combined resistance becomes 1 more linear, which is the desired effect. This gives us the linear looking curve for V TC654/TC655 --------------------------------------- - ...
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... Sense Pin Waveforms. 7.5 Output Drive Device Selection The TC654/TC655 is designed to drive two external NPN transistors or two external N-channel MOSFETs as the fan speed modulating elements. These two arrangements are shown in Figure 7-7. For lower cur- rent fans, NPN transistors are a very economical choice for the fan drive device ...
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... MOSFETs are very low, the TC654/TC655 can charge and discharge them very quickly, leading to very fast edges. Of key concern is the turn-off edge of the MOS- FET. Since the fan motor winding is essentially an inductor, once the MOSFET is turned off, the current that was flowing through the motor wants to continue to flow ...
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... IN 0.01 µF capacitor. In order to keep fan noise off of the TC654/TC655 device ground, individual ground returns for the TC654/ TC655 and the low side of the fan current sense resis- tor should be used. 7.7 Determining Current Pulses Per Revolution of Fans There are many different fan designs available in the marketplace today ...
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... This new sensing configuration is shown in Figure 7-12. The values of the resistor/capac- itor combination should be adjusted so that the voltage pulse generated by the extra current pulse is smoothed and is not registered by the TC654/TC655 as a true fan current pulse. Typical values for R SLOW are 1 K and 1000 pF, respectively ...
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... Standard device marking consists of Microchip part number, year code, week code, and traceability code. DS21734A-page 28 10-Pin MSOP Device 1 10 TC654E 9 2 TC655E YWWNNN 2002 Microchip Technology Inc. ...
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... Microchip Technology Inc. User Direction of Feed P Standard Reel Component Orientation for TR Suffix Device Pitch (P) Part Per Full Reel 8 mm 10-Pin MSOP .201 (5.10) .183 (4.65) 6 MAX. MAX. .028 (0.70) .016 (0.40) TC654/TC655 W Reel Size 2500 13 in. .009 (0.23) .005 (0.13) Dimensions: inches (mm) DS21734A-page 29 ...
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... TC654/TC655 NOTES: DS21734A-page 30 2002 Microchip Technology Inc. ...
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... Conferences for products, Development Systems, technical information and more • Listing of seminars and events 2002 Microchip Technology Inc. TC654/TC655 Systems Information and Upgrade Hot Line The Systems Information and Upgrade Line provides system users a listing of the latest versions of all of Microchip's development systems software products. ...
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... Telephone: (_______) _________ - _________ Application (optional): Would you like a reply? Y Device: TC654/TC655 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 data sheet easy to follow? If not, why? 4 ...
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... Microchip Technology Inc. TC654/TC655 Examples: a) TC654EUN: : PWM Fan Speed Controller w/Fault Detection b) TC654EUNTR: PWM Fan Speed Controller w/Fault Detection (Tape and Reel) c) TC655EUN: PWM Fan Speed Controller w/Fault Detection d) TC655EUNTR: PWM Fan Speed Controller w/Fault Detection (Tape and Reel) DS21734A-page33 ...
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... TC654/TC655 NOTES: DS21734A-page 34 2002 Microchip Technology Inc. ...
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... 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. 2002 Microchip Technology Inc. Trademarks The Microchip name and logo, the Microchip logo, FilterLab ...
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... Tel: 39-039-65791-1 Fax: 39-039-6899883 United Kingdom Microchip Ltd. 505 Eskdale Road Winnersh Triangle Wokingham Berkshire, England RG41 5TU Tel: 44 118 921 5869 Fax: 44-118 921-5820 Austria Microchip Technology Austria GmbH Durisolstrasse 2 A-4600 Wels Austria Tel: 43-7242-2244-399 Fax: 43-7242-2244-393 05/16/02 2002 Microchip Technology Inc. ...