emc2105 Standard Microsystems Corp., emc2105 Datasheet
emc2105
Related parts for emc2105
emc2105 Summary of contents
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... PRODUCT FEATURES General Description The EMC2105 is an SMBus compliant fan controller with up to five ( external and 1 internal)temperature channels. The fan driver can be operated using two methods each with two modes. The methods include an RPM based Fan Speed Control Algorithm and a direct drive setting ...
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... RPM-Based High Side Fan Controller with Hardware Thermal Shutdown ORDER NUMBER: PACKAGE 20 pin QFN Lead-Free Single High Side Fan driver 4external RoHS compliant diode measurement channels, one Critical / Thermal Shutdown input REEL SIZE IS 4,000 PIECES 2 DATASHEET Datasheet FEATURES SMSC EMC2105 ...
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... Aging Fan or Invalid Drive Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 5.7 Spin Up Routine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 5.8 Ramp Rate Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 5.9 Watchdog Timer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 5.10 Internal Thermal Shutdown (TSD 5.11 Fault Queue . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 5.12 Temperature Monitoring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 5.12.1 Dynamic Averaging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 5.12.2 Resistance Error Correction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 5.12.3 Beta Compensation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 5.12.4 Digital Averaging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 5.13 Thermistor Support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 5.14 Diode Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 5.14.1 Diode Faults . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 5.15 GPIOs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 5.16 Interrupts Chapter 6 Register Set . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38 SMSC EMC2105 3 DATASHEET Revision 1.74 (05-08-08) ...
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... Product Features Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72 6.40 Product ID Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73 6.41 Manufacturer ID Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73 6.42 Revision Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73 Chapter 7 Package Drawing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74 7.1 QFN 20-Pin 4mm x 4mm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74 7.2 Package Markings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75 Appendix A Thermistors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76 A.1 Thermistor Look Up Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77 Appendix B Look Up Table Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81 B.1 Example # Revision 1.74 (05-08-08) RPM-Based High Side Fan Controller with Hardware Thermal Shutdown 4 DATASHEET Datasheet SMSC EMC2105 ...
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... RPM-Based High Side Fan Controller with Hardware Thermal Shutdown Datasheet B.2 Example # B.3 Example # Appendix C RPM to Tachometer Count Look Up Table . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87 C.1 1k RPM Range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87 SMSC EMC2105 5 DATASHEET Revision 1.74 (05-08-08) ...
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... Figure 1.1 EMC2105 Block Diagram Figure 2.1 EMC2105 Pin Diagram (20 Pin QFN Figure 4.1 SMBus Timing Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 Figure 5.1 System Diagram of EMC2105 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 Figure 5.2 EMC2105 Critical/Thermal Shutdown Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Figure 5.3 Fan Control Look-Up Table Example Figure 5.4 RPM based Fan Speed Control Algorithm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 Figure 5.5 Spin Up Routine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 Figure 5.6 Ramp Rate Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 Figure 5 ...
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... RPM-Based High Side Fan Controller with Hardware Thermal Shutdown Datasheet List of Tables Table 2.1 Pin Description for EMC2105 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 Table 2.2 Pin Types Table 3.1 Absolute Maximum Ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 Table 3.2 Electrical Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 Table 3.3 SMBus Electrical Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 Table 4.1 Protocol Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 Table 4.2 Write Byte Protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 Table 4.3 Read Byte Protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 Table 4 ...
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... Table B.9 Fan Speed Control Table Example # Table B.10 Fan Speed Determination for Example #3 (using settings in Table C.1 Tachometer Count to RPM Look Up Table (Range = 1000 RPM Revision 1.74 (05-08-08) RPM-Based High Side Fan Controller with Hardware Thermal Shutdown Table B. Table B. Table B. DATASHEET Datasheet SMSC EMC2105 ...
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... Tachs CLK_IN* SMSC EMC2105 Thermal Shutdown Logic 11 bit Σ Δ Temp Limit Registers ADC Temp Registers Configuration Lookup Table / RPM Control * denotes multiple pin functions Figure 1.1 EMC2105 Block Diagram 9 DATASHEET SMCLK SMBus SMDATA Slave ALERT# Protocol VREF* Reference GPIO1* GPIO Revision 1.74 (05-08-08) ...
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... Chapter 2 Pin Description DN1 / VIN1 1 2 DP1 / VREF_T1 GND 3 VDD 4 ALERT# 5 Figure 2.1 EMC2105 Pin Diagram (20 Pin QFN) Revision 1.74 (05-08-08) RPM-Based High Side Fan Controller with Hardware Thermal Shutdown 15 TRIP_SET / VIN4 14 VDD_5V EMC2105 13 VDD_5V 20-QFN FAN_OUT 12 11 FAN_OUT 10 DATASHEET Datasheet SMSC EMC2105 ...
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... VDD_5V 14 VDD_5V 15 TRIP_SET / VIN4 16 SHDN_SEL SMSC EMC2105 Table 2.1 Pin Description for EMC2105 PIN FUNCTION DN1 - Negative (cathode) analog input for External Diode 1 (default) VIN1 - General voltage input for use with a thermistor DP1 - Positive (anode) analog input for External Diode 1 (default) VREF_T1 - Reference output for use with ...
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... AI AO AIO DO Revision 1.74 (05-08-08) RPM-Based High Side Fan Controller with Hardware Thermal Shutdown Table 2.1 Pin Description for EMC2105 PIN FUNCTION DN3 / DP4 - Negative (cathode) analog input for External Diode 3 and positive (anode) Analog Input for External Diode 4 (default) VIN3 - General voltage input for use with ...
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... RPM-Based High Side Fan Controller with Hardware Thermal Shutdown Datasheet PIN TYPE DIOD OD SMSC EMC2105 Table 2.2 Pin Types (continued) DESCRIPTION Digital Input / Open Drain Output this pin is used as an digital I/O. When it is used as an output open drain and requires a pull-up resistor. This pin is 5V tolerant. ...
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... Typical values noted. MIN TYP MAX UNIT DC Power 3 3.3 3 DATASHEET Datasheet 85° °C/W °C ° 27°C unless otherwise A CONDITIONS Conversions / second - Dynamic Averaging Enabled Fan Driver enabled SMSC EMC2105 ...
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... Voltage Accuracy V FAN_OUT Fan Drive Current I SOURCE Overcurrent Limit I OVER DC Short Circuit I SHORT Current Limit Short circuit delay t DFS SMSC EMC2105 = -40°C to 85°C, all Typical values noted. MIN TYP MAX UNIT 500 750 uA 100 uA External Temperature Monitors ±0.25 ±1 ° ...
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... DATASHEET Datasheet = 27°C unless otherwise A CONDITIONS Ω Z < 100m at 10kHz ESR External oscillator 32.768kHz Internal Oscillator 40°C < T < 100°C DIE 4 mA current drive 4 mA current sink ALERT and SYS_SHDN pins Powered and unpowered due to self heating DIE SMSC EMC2105 ...
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... Data Hold Time t HD:DAT Data Setup Time t SU:DAT Clock Low Period t LOW Clock High Period t HIGH Clock/Data Fall time t FALL Clock/Data Rise time t RISE Capacitive Load C LOAD SMSC EMC2105 A MIN TYP MAX UNITS SMBus Interface 2.0 V 0.8 V VDD V - 0.4 0.4 V ± ...
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... Chapter 4 Communications 4.1 System Management Bus Interface Protocol The EMC2105 communicates with a host controller, such as an SMSC SIO, through the SMBus. The SMBus is a two-wire serial communication protocol between a computer host and its peripheral devices. A detailed timing diagram is shown in however the EMC2105 will not stretch the clock signal. ...
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... All devices with active interrupts will respond with their client address as shown in Table Table 4.6 Alert Response Address Protocol ALERT RESPONSE START ADDRESS 0 -> 1 0001_100 SMSC EMC2105 Table 4.3 Read Byte Protocol ACK START Slave Address XXh 0 0 -> 1 0101_111 Table 4 ...
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... The EMC2105 will respond to the ARA in the following way if the ALERT# pin is asserted. 1. Send Slave Address and verify that full slave address was sent (i.e. the SMBus communication from the device was not prematurely stopped due to a bus contention event). 2. Set the MASK bit to clear the ALERT# pin. ...
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... Datasheet Chapter 5 Product Description The EMC2105 is an SMBus compliant fan controller with up to four ( external) temperature channels. It contains a single High Side fan driver capable of sourcing up to 600mA from a 5V supply. The fan driver can be operated using two methods each with two modes. The methods include an RPM based Fan Speed Control Algorithm and a direct fan drive setting ...
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... Critical/Thermal Shutdown The EMC2105 provides a hardware Critical/Thermal Shutdown function for systems. block diagram of this Critical/Thermal Shutdown function. The Critical/Thermal Shutdown function in the EMC2105 accepts configuration information from the fixed states of the SHDN_SEL pin as described in Section 5.1.1. Each of the software programmed temperature limits can be optionally configured to act as inputs to the Critical / Thermal Shutdown independent of the hardware shutdown operation ...
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... The EMC2105 has a ‘strappable’ input (SHDN_SEL) allowing for configuration of the hardware Critical/Thermal Shutdown input channels. This pin has 3 possible states and is monitored and decoded by the EMC2105 at power-up. The three possible states are 0 (tied to GND), 1 (tied to 3.3V) or High-Z (open). The state of this pin determines which external diode configuration is used for the Critical / Thermal shutdown function ...
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... SMSC EMC2105 ...
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... Fan Control Modes of Operation The EMC2105 has four modes of operation for the fan driver. Each mode of operation uses the Ramp Rate control and Spin Up Routine. 1. Direct Setting Mode- in this mode of operation, the user directly controls the fan drive setting. Updating the Fan Driver Setting Register (see Ramp Rate control is optional and enabled via the EN_RRC bits ...
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... High Side Fan Driver The EMC2105’s contains a 5V, 600mA, linear high side fan driver to directly drive a 5V fan. By fully integrating the linear fan driver, the typical requirement for the discrete pass device and other external linearization circuitry is completely eliminated. The linear fan driver is driven by an 8-bit DAC providing better than 20mV resolution between steps ...
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... Fan Control Look-Up Table The EMC2105 uses a look-up table to apply a user-programmable fan control profile based on measured temperature to the fan driver. In this look-up table, each temperature channel is allowed to control the fan drive output independently (or jointly) by programming up to eight pairs of temperature and drive setting entries ...
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... For each step to be used in the LUT, set each of the measurement channel thresholds. These values must be set in the same data format that the data is presented. If DTS used, then Revision 1.74 (05-08-08) RPM-Based High Side Fan Controller with Hardware Thermal Shutdown Fan Setting Measurement taken Time 28 DATASHEET Datasheet Fan Setting SMSC EMC2105 ...
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... ALERT# pin. The EMC2105 works with fans that operate up to 16,000 RPMs and provide a valid tachometer signal. The fan controller will function either with an externally supplied 32.768KHz clock source or with it’s own internal 32kHz oscillator depending on the required accuracy ...
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... RPM-Based High Side Fan Controller with Hardware Thermal Shutdown Set TACH Target Count Measure Fan Speed Spin Up Yes Perform Spin Up Required Routine ? No TACH Yes Reading = TACH Target? No TACH No Yes Reading < TACH Target? Increase Fan Drive 30 DATASHEET Datasheet Ramp Rate Control SMSC EMC2105 ...
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... The RPM based Fan Speed Control Algorithm is disabled upon device power up. The following registers control the algorithm. The EMC2105 fan control registers are pre-loaded with defaults that will work for a wide variety of fans so only the TACH Target Register is required to set a fan speed. ...
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... For the remaining spin up time, the fan driver output is set a a user defined level (30% through 65% drive). After the Spin Up Routine has finished, the EMC2105 measures the TACHx signal. If the measured TACH Reading Register value is higher than the Valid TACH Count Register setting, the FAN_SPIN status bit is set and the Spin Up Routine will automatically attempt to restart the fan ...
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... If this delta is greater than the Max Step settings, then the fan drive setting is incrementally adjusted every 100ms to 1.6s as determined by the Update Time until the target fan drive setting is reached. See SMSC EMC2105 New Target Count Update Time Check TACH ...
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... Watchdog Timer The EMC2105 contains an internal Watchdog Timer. Once the device has powered up the watchdog timer monitors the SMBus traffic for signs of activity. The Watchdog Timer starts when the internal supply has reached its operating point. The Watchdog Timer only starts immediately after power-up and once it has been triggered or deactivated will not restart ...
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... Temperature Monitoring The EMC2105 can monitor the temperature four (4) externally connected diodes as well as the internal or ambient temperature. Each channel is configured with the following features enabled or disabled based on user settings and system requirements. APPLICATION NOTE: When measuring an Intel 45nm CPU, the reported temperature will have an error of approximately 1.5° ...
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... Resistance Error Correction The EMC2105 includes active Resistance Error Correction to remove the effect 100 ohms of series resistance. Without this automatic feature, voltage developed across the parasitic resistance in the remote diode path causes the temperature to read higher than the true temperature is. The error induced by parasitic resistance is approximately +0.7° ...
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... External Diode 3 and External Diode 4 channels. 5.15 GPIOs The EMC2105 contains a single GPIO pin (multiplexed with other functions). The GPIO pin can be configured as an input or an output and as a push-pull or open-drain output. Additionally, the GPIO pin, when configured as an input, can be enabled to trigger an interrupt when it changes states. ...
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... Shutdown Temperature Pushed 0Ch R/W Temperature 1 Revision 1.74 (05-08-08) RPM-Based High Side Fan Controller with Hardware Thermal Shutdown Table 6.1 EMC2105 Register Set FUNCTION Temperature Registers Stores the integer data of the Internal Diode Stores the fractional data of the Internal Diode Stores the integer data of External ...
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... RPM-Based High Side Fan Controller with Hardware Thermal Shutdown Datasheet Table 6.1 EMC2105 Register Set (continued) REGISTER ADDR R/W NAME Pushed 0Dh R/W Temperature 2 10h R Trip Set Voltage External Diode 1 14h R/W Beta Configuration External Diode 2 15h R/W Beta Configuration External Diode 3 16h R/W Beta Configuration External Diode ...
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... Table 6.1 EMC2105 Register Set (continued) REGISTER ADDR R/W NAME 26h R-C Diode Fault 27h R-C Fan Status Interrupt Enable 28h R/W Register Fan Interrupt 29h R/W Enable Register External Diode 1 30h R/W Temp High Limit External Diode 2 31h R/W Temp High Limit External Diode 3 32h R/W Temp High Limit ...
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... RPM-Based High Side Fan Controller with Hardware Thermal Shutdown Datasheet Table 6.1 EMC2105 Register Set (continued) REGISTER ADDR R/W NAME Fan 43h R/W Configuration 2 45h R/W Gain Fan Spin Up 46h R/W Configuration 47h R/W Fan Step Fan Minimum 48h R/W Drive Fan Valid TACH 49h R/W Count Fan Drive Fail ...
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... Table 6.1 EMC2105 Register Set (continued) REGISTER ADDR R/W NAME LUT Temp 4 55h R/W Setting 1 56h R/W LUT Drive 2 LUT Temp 1 57h R/W Setting 2 LUT Temp 2 58h R/W Setting 2 LUT Temp 3 59h R/W Setting 2 LUT Temp 4 5Ah R/W Setting 2 5Bh R/W LUT Drive 3 LUT Temp 1 5Ch R/W Setting 3 LUT Temp 2 5Dh ...
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... RPM-Based High Side Fan Controller with Hardware Thermal Shutdown Datasheet Table 6.1 EMC2105 Register Set (continued) REGISTER ADDR R/W NAME LUT Temp 3 63h R/W Setting 4 LUT Temp 4 64h R/W Setting 4 65h R/W LUT Drive 5 LUT Temp 1 66h R/W Setting 5 LUT Temp 2 67h R/W Setting 5 LUT Temp 3 68h R/W Setting 5 ...
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... Table 6.1 EMC2105 Register Set (continued) REGISTER ADDR R/W NAME LUT Temp 2 71h R/W Setting 7 LUT Temp 3 72h R/W Setting 7 LUT Temp 4 73h R/W Setting 7 74h R/W LUT Drive 8 LUT Temp 1 75h R/W Setting 8 LUT Temp 2 76h R/W Setting 8 LUT Temp 3 77h R/W Setting 8 LUT Temp 4 78h R/W Setting 8 LUT Temp ...
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... RPM-Based High Side Fan Controller with Hardware Thermal Shutdown Datasheet Table 6.1 EMC2105 Register Set (continued) REGISTER ADDR R/W NAME E6h R GPIO Status EF R/W Software Lock FCh R Product Features FDh R Product ID FEh R Manufacturer ID FFh R Revision During Power-On-Reset (POR), the default values are stored in the registers. A POR is initiated when power is first applied to the part and the voltage on the VDD supply surpasses the POR level as specified in the electrical characteristics ...
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... DATASHEET Datasheet DEFAULT - - - - 13.5 6.25 3.125 - - - - HEX (AS READ BY REGISTERS) 80_00h C0_20h C1_00h FF_00h FF_E0h 00_00h 00_20h 01_00h 3F_00h 40_00h 41_00h SMSC EMC2105 00h 00h 00h 00h 00h 00h ...
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... TEMPERATURE (° 127 130 150 6.4 Pushed Temperature Registers ADDR R/W REGISTER Pushed 0Ch R/W Temperature 1 Pushed 0Dh R/W Temperature 2 SMSC EMC2105 Table 6.3 Temperature Data Format (continued) BINARY 0111_1111_000b 0111_1111_111b 128 Table 6.5. BINARY 0000_0000b 0000_0001b 0011_1111b 0100_0000b 0100_0001b 0111_1111b 1000_0010b 1001_0110b Table 6 ...
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... RPM-Based High Side Fan Controller with Hardware Thermal Shutdown Table 6.7 TripSet Voltage Register 400 200 100 50 Table 6.8 Beta Configuration Registers AUTO - - - AUTO - - - AUTO Table 6.1). 48 DATASHEET Datasheet Table 6. DEFAULT 25 13.5 6.25 3.125 DEFAULT BETA1[3:0] BETA2[3:0] BETA3[3:0] SMSC EMC2105 FFh 10h 10h 10h ...
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... Configuration The REC Configuration Register determines whether Resistance Error Correction is used for each external diode channel. The REC Configuration Register is software locked. SMSC EMC2105 for supported beta ranges. A value of 1111b indicates that the beta compensation Table 6.9 Beta Compensation Look Up Table BETAX[3:0] ...
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... DATASHEET Datasheet Table 6.1 SYS3 SYS2 SYS1 APD SMSC EMC2105 DEFAULT 64h (+100°C) 64h (+100°C) 64h (+100°C) 64h (+100°C) 64h (+100°C) DEFAULT 00h ...
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... RPM-Based High Side Fan Controller with Hardware Thermal Shutdown Datasheet The Configuration Register controls the basic functionality of the EMC2105. The bits are described below. The Configuration Register is software locked. Bit 7 - MASK - Blocks the ALERT# pin from being asserted. ‘0’ (default) - The ALERT# pin is unmasked. If any bit in either status register is set, the ALERT# pins will be asserted (unless individually masked via the Mask Register) ‘ ...
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... NUMBER OF CONSECUTIVE OUT OF LIMIT CONDITIONS Table 6.15 Conversion Rate CONVERSION RATE 1 / sec 2 / sec 4 / sec (default) Continuous 52 DATASHEET Datasheet 2 C compliant. 1 (disabled (default) TEMPERATURE OVER SAMPLING FROM 11 BITS DYN_DIS = ‘0’ DYN_DIS = ‘1’ SMSC EMC2105 ...
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... Status Register The Interrupt Status Register reports the operating condition of the EMC2105. If any of the bits are set to a logic ‘1’ (other than TSD and HWS) then the ALERT# pin will be asserted low if the corresponding channel is enabled. Reading from the status register clears all status bits if the error conditions is removed ...
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... LO EXT4_ - - - FLT 54 DATASHEET Datasheet EXT3_ EXT2_ EXT1 INT_ CRIT CRIT _CRIT CRIT EXT3_ EXT2_ EXT1 INT_ HI HI _HI HI EXT3_ EXT2_ EXT1 INT_L LO LO _LO O EXT3_ EXT2_ EXT1 - FLT FLT _FLT SMSC EMC2105 DEFAULT 00h 00h 00h 00h ...
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... ALERT# pin to be asserted when an error condition is detected. Bit 5 - VOLT4_INT_EN - Allows the Voltage Input 4 channel to assert the ALERT# pin. ‘0’ (default) - The ALERT# pin will be not be asserted for any error condition associated with Voltage Channel 4 (TRIP_SET / VIN4). SMSC EMC2105 Table 6.19 Fan Status Register B7 B6 ...
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... FAN_STALL or DRIVE_FAIL bit will assert the ALERT# pin if set. Revision 1.74 (05-08-08) RPM-Based High Side Fan Controller with Hardware Thermal Shutdown Table 6.21 Fan Interrupt Enable Register DATASHEET Datasheet SPIN_ STALL_ - - INT_EN INT_EN SMSC EMC2105 DEFAULT 00h ...
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... R/W Limit The EMC2105 contains high limits for all temperature channels and voltage channels. If any measurement meets or exceeds the high limit then the appropriate status bit is set and the ALERT# pin are asserted (if enabled). APPLICATION NOTE: If any of the External Diode 1, External Diode 2, External Diode 3 is configured to operate as a voltage input, then the corresponding temperature high and low limit registers are compared against the measured voltage ...
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... Table 6.23 Fan Driver Setting Register 128 ⎛ ⎞ VALUE × -------------------- - = VDD_5V ⎝ ⎠ 255 Table 6.24 Fan Configuration 1 Register EN_ RANGE[1:0] EDGES[1:0] ALGO Table 6.25. 58 DATASHEET Datasheet DEFAULT 00h Equation [2]. [ DEFAULT UPDATE[2:0] 2Bh SMSC EMC2105 ...
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... Fan Step Register, is used to control the ramp rate of the drive response to provide a cleaner transition of the actual fan operation as the desired fan speed changes. The Update Time is set as shown in Table 6.27. UPDATE[2: SMSC EMC2105 Table 6.25 Range Decode REPORTED MINIMUM 1000 (default EDGES NUMBER OF FAN POLES 3 1 pole 5 ...
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... Table 6.27 Update Time (continued) UPDATE[2: Table 6.28 Fan Configuration 1 Register EN_ GLITCH - DER_OPT [1:0] RRC _EN1 60 DATASHEET Datasheet UPDATE TIME 400ms (default) 500ms 800ms 1200ms 1600ms ERR_RNG[1:0] - Table 6.27. Table 6.29. SMSC EMC2105 DEFAULT 38h ...
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... The Gain Register stores the gain terms used by the proportional and integral portions of each of the RPM based Fan Speed Control Algorithms. These gain terms are used as the KD, KI, and KP gain terms in a classic PID control solution. SMSC EMC2105 Table 6.29 Derivative Options 0 0 Basic derivative ...
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... Drive Fail detection circuitry will count for 16 update periods 32 - the Drive Fail detection circuitry will count for 32 update periods 64 - the Drive Fail detection circuitry will count for 64 update periods 62 DATASHEET Datasheet (default DEFAULT SPINUP_TIM 0Dh E [1:0] SMSC EMC2105 ...
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... The Fan Step Register, along with the Update Time, controls the ramp rate of the fan driver response calculated by the RPM based Fan Speed Control Algorithm. The value of the registers represents the maximum step size each fan driver will take between update times (see SMSC EMC2105 Table 6.35 Spin Level 1 ...
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... Algorithm, the Look Up Table manual settings) exceeds the current fan drive setting by greater than the Fan Step Register setting, the EMC2105 will limit the fan drive change to the value of the Fan Step Register. It will use the Update Time to determine how often to update the drive settings ...
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... FFh) will cause the algorithm to invoke the Spin Up Routine after which it will function normally. The Tach Target is not applied until the high byte is written. Once the high byte is written, the current value of both high and low bytes will be used as the next Tach target. 3 SMSC EMC2105 B7 B6 ...
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... TACH measurement frequency (typically 32.768kHz number of edges measured (typically 5 for a 2 pole fan the multiplier defined by the RANGe bits COUNT = TACH Reading Register value (in decimal TEMP3_CFG TEMP4_CFG [1:0] [1:0] SMSC EMC2105 [3] [4] DEFAULT 00h ...
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... Temperature 3 inputs to the Look Up Table as shown in TEMP3_CFG [1: Bits 1-0 - TEMP4_CFG[1:0] - These bits determine the temperature channel that is used for the Temperature 4 inputs to the Look Up Table as shown in SMSC EMC2105 Table Table 6.44 TEMP3_CFG Decode 0 TEMPERATURE CHANNEL USED 0 External Diode 3 (default) 1 TRIP_SET / VIN4 Voltage ...
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... 512 256 128 47.06 23.53 11.76 5. 47.06 23.53 11.76 5. 47.06 23.53 11.76 5. ... ... ... ... 512 256 128 SMSC EMC2105 Datasheet B0 DEFAULT 32 FBh 1 7Fh 1 (127°C) 7Fh (0.4V) 7Fh 1 (127°C) 7Fh (0.4V) 7Fh 1 (127°C) 7Fh (0.4V) 7Fh 1 (127°C) ... .. . 32 92h 1 ...
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... RPM based Fan Speed Control Algorithm configuration settings. If the RPM based Fan Speed Control Algorithm is not used, then the fan drive setting is updated after every conversion set to the maximum duty cycle that is stored by the Look Up Table. SMSC EMC2105 Table 6.46 Look Up Table Registers (continued ...
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... Table 6.47 Muxed Pin Configuration Register Table 6.48 GPIO Direction Register Table 6.49 GPIO Pin Output Configuration Register DATASHEET Datasheet GPIO1 - - - _CFG DEFAULT GPIO - - - 1_DIR DEFAULT GPIO - - - 1_OT SMSC EMC2105 DEFAULT 01h 00h 00h ...
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... The ALERT# pin will not be asserted when the GPIO1 pin changes state (when configured as an input). ‘1’ - The ALERT# pin will be asserted when the GPIO1pin changes state (when configured as an input). SMSC EMC2105 Table 6.50 GPIO Input Register B7 B6 ...
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... RPM-Based High Side Fan Controller with Hardware Thermal Shutdown Table 6.53 GPIO Status Register Table 6.54 Software Lock Register Table 6.55 Product Features Register DATASHEET SHDN_SEL[1:0] SMSC EMC2105 Datasheet B0 DEFAULT GPIO1_ 00h STS B0 DEFAULT LOCK 00h DEFAULT 00h ...
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... Revision Register ADDR R/W REGISTER FFh R Revision The Revision Register contains a 8 bit word that identifies the die revision. SMSC EMC2105 Table 6.56 SHDN_SEL Bit Decode CRITICAL / THERMAL EXTERNAL DIODE 1 MODE TEMPERATURE RANGE Transistor mode - Beta = automatic High range - 92°C to 154°C REC = enabled ...
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... Chapter 7 Package Drawing 7.1 QFN 20-Pin 4mm x 4mm Figure 7.1 EMC2105 20-Pin 4x4mm QFN Package Outline and Parameters Revision 1.74 (05-08-08) RPM-Based High Side Fan Controller with Hardware Thermal Shutdown 74 DATASHEET Datasheet SMSC EMC2105 ...
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... All devices will be marked on the first line of the top side with “2105”. On the second line, they will be marked the Lot Number, and on the third line, they will be marked with the Functional Revision “C” and Country Code. SMSC EMC2105 75 DATASHEET ...
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... Appendix A Thermistors The EMC2105 can monitor thermistor inputs on the TRIP_SET / VIN4 as well as supporting a thermistor option on the all of the external diode pins pairs (DP1 / VREF_T1 and DN1 / VIN1,etc.). The Thermistors can be connected as shown in Figure A.1 is representative of one of the thermistor channels and will apply to DP1 / VREF_T1 and DN1 / VIN1, DP2 / VREF_T2 and DN2 / VIN2 ...
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... SMSC EMC2105 ADC T ADC CODE (°C) CODE 235 75 157 235 76 155 234 77 154 233 78 152 232 79 150 231 80 148 231 81 146 230 ...
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... DATASHEET Datasheet T ADC (°C) CODE 165 46 166 46 167 45 168 44 169 44 170 43 171 43 172 42 173 41 174 41 175 40 176 40 177 39 178 38 179 38 180 37 181 37 182 36 183 36 184 35 185 35 186 34 187 34 188 33 189 33 190 32 191 32 SMSC EMC2105 ...
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... SMSC EMC2105 ADC T ADC CODE (°C) CODE 100 21 78 102 22 79 104 23 80 106 23 81 108 24 82 109 25 83 111 ...
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... SMSC EMC2105 ...
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... RPM-Based High Side Fan Controller with Hardware Thermal Shutdown Datasheet Appendix B Look Up Table Operation The EMC2105 uses a look-up table to apply a user-programmable fan control profile based on measured temperature to the fan driver. In this look-up table, each temperature channel is allowed to control the fan drive output independently (or jointly) by programming up to eight pairs of temperature and drive setting entries ...
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... 100% Table B.3) INTERNAL DIODE TEMPERATURE FAN DRIVE (AMBIENT) SETTING RESULT 70% (CPU temp 58°C requires highest drive) 80% (GPU and Skin 58°C require highest drive) 100% (Internal temp 75°C requires highest drive) SMSC EMC2105 Datasheet SETTING C0h ...
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... Table B.6 Fan Speed Control Table Example #2 FAN EXTERNAL DIODE SPEED 1 TEMPERATURE STEP # (CPU SMSC EMC2105 VIN4_I VIN3_E VIN3_I VIN2_ RANGE[1:0] EDGES[1: NOKICK SPIN_LVL[2: ...
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... RPM) 08h (7680 RPM) Table B.6) INTERNAL DIODE TEMPERATURE FAN DRIVE (AMBIENT) SETTING RESULT 0Ch (5120RPM) - 58°C CPU requires highest target 09h (6826 RPM) 58°C Thermistor requires highest target 09h (6826 RPM) Pushed Temperature 58°C requires highest target SMSC EMC2105 ...
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... SPEED 1 TEMPERATURE STEP # (CPU SMSC EMC2105 shows how the table is loaded RANGE[1:0] EDGES[1: NOKICK SPIN_LVL[2: USE_D LUT_LO TACH / TEMP3_CFG TS_F2 CK DRIVE EXTERNAL DIODE 2 ...
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... PUSHED TEMPERATURE FAN DRIVE (DTS2) SETTING RESULT 0Ch (5120 RPM) - 50°C CPU requires highest (translated as 50°C) target 08h (7680 RPM) - 20°C DTS1 requires (translated as 80°C) highest target 5°C 09h (6826 RPM) - (translated as DTS2 requires highest target 95°C) SMSC EMC2105 ...
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... SMSC EMC2105 FAN SPEED TACH COUNT (RPM) (DECIMAL) Disabled 4096 245760 4128 122880 4160 81920 4192 61440 4224 49152 4256 40960 4288 35109 4320 30720 4352 27307 4384 24576 ...
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... DATASHEET Datasheet REGISTER READING FAN SPEED (HEX) (RPM) 99 1606 9A 1596 9B 1586 9C 1575 9D 1565 9E 1555 9F 1546 A0 1536 A1 1526 A2 1517 A3 1508 A4 1499 A5 1489 A6 1480 A7 1472 A8 1463 A9 1454 AA 1446 AB 1437 AC 1429 AD 1421 AE 1412 AF 1404 B0 1396 B1 1388 B2 1381 B3 1373 B4 1365 B5 1358 B6 1350 B7 1343 SMSC EMC2105 ...
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... SMSC EMC2105 FAN SPEED TACH COUNT (RPM) (DECIMAL) 4389 5888 4312 5920 4237 5952 4165 5984 4096 6016 4029 6048 3964 6080 3901 6112 3840 6144 3781 6176 3724 ...
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... DATASHEET Datasheet REGISTER READING FAN SPEED (HEX) (RPM) D8 1138 D9 1133 DA 1127 DB 1122 DC 1117 DD 1112 DE 1107 DF 1102 E0 1097 E1 1092 E2 1087 E3 1083 E4 1078 E5 1073 E6 1069 E7 1064 E8 1059 E9 1055 EA 1050 EB 1046 EC 1041 ED 1037 EE 1033 EF 1028 F0 1024 F1 1020 F2 1016 F3 1011 F4 1007 F5 1003 F6 999 SMSC EMC2105 ...
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... TACH COUNT REGISTER (DECIMAL) READING (HEX) 3808 77 3840 78 3872 79 3904 7A 3936 7B 3968 7C 4000 7D 4032 7E 4064 7F SMSC EMC2105 FAN SPEED TACH COUNT (RPM) (DECIMAL) 2065 7904 2048 7936 2031 7968 2014 8000 1998 8032 1982 8064 1966 8096 1950 8128 1935 8160 ...