emc1428 Standard Microsystems Corp., emc1428 Datasheet
emc1428
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emc1428 Summary of contents
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... PRODUCT FEATURES General Description The EMC1428 is a high accuracy, low cost, System Management Bus (SMBus) temperature sensor. Advanced features such as Resistance Error Correction (REC), Beta Compensation (to CPU diodes requiring the BJT or transistor model) and automatic diode type detection combine to provide a robust solution for complex environmental monitoring applications ...
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... Hardware set Critical / Thermal shutdown, ALERT output Reel Size is 4,000 pieces 2 DATASHEET Datasheet DIODE MODES SMBUS SUPPORTED ADDRESS Intel CPU and 1001_100(r/w) 3904 Intel CPU and 1001_101(r/w) 3904 Intel CPU and Selected by 3904 pull-up resistor on SYS_SHDN pin SMSC EMC1428 ...
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... Therm Hysteresis Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 5.8 Therm Limit Registers 5.9 External Diode Fault Register 5.10 TRIP_SET Reading Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 5.11 Software Thermal Shutdown Configuration Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 5.12 Hardware Critical / Thermal Shutdown Limit Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 5.13 Channel Interrupt Mask Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 5.14 Consecutive ALERT Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 5.15 Beta Configuration Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39 5.16 Hottest Temperature Registers SMSC EMC1428 3 DATASHEET Revision 0.68 (07-08-08) ...
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... Channel Configuration Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44 5.24 Filter Control Register 5.25 Product ID Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 5.26 Manufacturer ID Register (FEh 5.27 Revision Register (FFh Chapter 6 Package Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46 6.1 EMC1428 Package Drawing 6.2 Package Markings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48 6.2.1 EMC1428-X-AP (16-Pin QFN Revision 0.68 (07-08-08) 1°C Multiple Temperature Sensor with HW Thermal Shutdown & Hottest of Thermal Zones 4 DATASHEET Datasheet SMSC EMC1428 ...
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... Multiple Temperature Sensor with HW Thermal Shutdown & Hottest of Thermal Zones Datasheet List of Figures Figure 1.1 EMC1428 Pin Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Figure 3.1 SMBus Timing Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Figure 4.1 System Diagram for EMC1428 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Figure 4.2 Block Diagram of Hardware Thermal Shutdown . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 Figure 4.3 Vset Circuit Figure 4.4 Diode Connections Figure 6.1 16-Pin QFN 4mm x 4mm Package Dimensions Figure 6 ...
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... Table 3.6 Alert Response Address Protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Table 3.7 Address Select Decode on SYS_SHDN Pin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 Table 4.1 V Resistor Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 TRIP Table 4.2 Supply Current vs. Conversion Rate for EMC1428 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 Table 5.1 Register Set in Hexadecimal Order . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 Table 5.2 Temperature Data Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 Table 5.3 Temperature Data Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 Table 5.4 Status Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 Table 5.5 Configuration Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 Table 5 ...
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... EMC1428 QFN Figure 1.1 EMC1428 Pin Diagram Table 1.1 EMC1428 Pin Description FUNCTION DP1 - External Diode 1 positive (anode) connection. External Diode 1 negative (cathode) connection. External Diode 2 positive (anode) connection and External Diode 3 negative (cathode) connection External diode 2 negative (cathode) connection and External Diode 3 ...
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... Table 1.1 EMC1428 Pin Description (continued) PIN NUMBER NAME 6 SYS_SHDN 7 ALERT 8 GND 9 DN4 / DP5 10 DP4 / DN5 11 SMDATA 12 SMCLK 13 N/C 14 DN6 / DP7 15 DP6 / DN7 16 VDD The pin types are described below. All pins labelled (5V) are 5V tolerant: PIN TYPE Power Used to supply either VDD or GND to the device ...
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... V = 3.0V to 3.6V -40°C to 125°C, all typical values CHARACTERISTIC SYMBOL Supply Voltage V DD Supply Current I DD Supply Current I DD SMSC EMC1428 Table 2.1 Absolute Maximum Ratings Refer to JEDEC Spec. J-STD- Table 2.2 Electrical Specifications A MIN TYP MAX UNITS DC Power 3.0 3.3 3.6 V 450 600 ...
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... Connected across external diode In series with DP and DN lines resistor SET (see Note 2. 8mA SINK powered or unpowered T < 85°C A Time after power up before all channels updated with valid data Delay before SMBus communications should be sent by host Table 4.1. CONDITIONS SMSC EMC1428 ...
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... SU:DAT Clock Low Period t LOW Clock High Period t HIGH Clock/Data Fall time t FALL Clock/Data Rise time t RISE Clock/Data Rise time t RISE Capacitive Load C LOAD SMSC EMC1428 = 27°C unless otherwise noted. A MIN TYP MAX UNITS 2 Tolerant DD -0.3 0 Tolerant ±5 uA Powered or unpowered ...
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... Chapter 3 System Management Bus Interface Protocol 3.1 System Management Bus Interface Protocol The EMC1428 communicate 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 ...
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... All devices with active interrupts will respond with their client address as shown in Table 3.6 Alert Response Address Protocol ALERT RESPONSE START ADDRESS 1 -> 0 0001_100 SMSC EMC1428 Table 3.3 Read Byte Protocol ACK START SLAVE ADDRESS XXh 0 0 -> 1 1001_100 Table 3 ...
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... Note: Other addresses are available. Contact SMSC for more information. 3.8 SMBus Timeout The EMC1428 support SMBus Timeout. If the clock line is held low for longer than 30ms, the device will reset its SMBus protocol. This function can be enabled by setting the TIMEOUT bit in the Consecutive Alert Register (see Revision 0.68 (07-08-08) 1° ...
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... EMC1428 and using that data to control the speed of one or more fans. The EMC1428 device has two levels of monitoring. The first provides a maskable ALERT signal to the host when measured temperatures meet or exceed user programmable limits. This allows the EMC1428 to be used as an independent thermal watchdog to warn the host of temperature hot spots without constant monitoring by the host ...
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... SYS_SHDN pin is asserted. Figure 4.2 shows a block diagram of the interaction between the input channels and the SYS_SHDN pin. Revision 0.68 (07-08-08) 1°C Multiple Temperature Sensor with HW Thermal Shutdown & Hottest of Thermal Zones Section 5.14). Section 5.14). 16 DATASHEET Datasheet SMSC EMC1428 ...
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... Figure 4.2 Block Diagram of Hardware Thermal Shutdown 4.3 TRIP_SET Pin The EMC1428’s TRIP_SET pin is an input to the Critical / Thermal Shutdown logic block which sets the Critical / Thermal shutdown temperature. The system designer creates a voltage level at this input through a simple resistor connected to GND as shown in to create an input voltage on the TRIP_SET pin which is translated into a temperature ranging from 65° ...
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... DATASHEET Datasheet Reference Voltage RSET (Ω) 1240.0 1330.0 1400.0 1500.0 1580.0 1690.0 1820.0 1960.0 2050.0 2210.0 2370.0 2550.0 2740.0 2940.0 3160.0 3480.0 3740.0 SMSC EMC1428 ...
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... Resistance Error Correction The EMC1428 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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... Diode channels to determine which of these channels is reporting the hottest temperature. The hottest temperature is stored in the Hottest Temperature Registers and the appropriate status bit in the Hottest Status Register is set optional feature, the EMC1428 can also flag an event if the hottest temperature channel changes. For example, suppose that External Diode channels 1, 3, and 4 are programmed to be compared in the “ ...
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... Diode Connections The diode connection for the External Diode 1 channel is determined based on the selected device. For the EMC1428, this channel can support a diode-connected transistor (such as a 2N3904 substrate transistor (such as those found in an CPU or GPU) as shown in diodes are not supported on the External Diode 1 channel. ...
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... Diode Faults The EMC1428 actively detects an open and short condition on each measurement channel. When a diode fault is detected, the temperature data MSByte is forced to a value of 80h and the FAULT bit is set in the Status Register. When an external diode channel is configured to operate in APD mode, the circuitry will detect independent open fault conditions, however a short condition will be shared between the APD channels ...
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... R/W Internal Diode Low Limit 0Dh R/W External Diode 1 High Limit High Byte SMSC EMC1428 Table 5.1 are accessible through the SMBus. An entry of ‘-’ indicates that the FUNCTION Stores the integer data for the Internal Diode Stores the integer data for the External Diode 1 ...
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... Page 31 (0°C) 00h Page 31 00h Page 31 55h Page 34 (85°C) 55h Page 34 (85°C) 00h Page 35 00h Page 35 00h Page 36 N/A Page 36 F0h Page 37 55h Page 34 (85°C) 0Ah Page 34 (10°C) 70h Page 37 00h Page 28 SMSC EMC1428 ...
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... REC Configuration 3Ah R/W Hottest Config 3Bh R/W Channel Config 40h R/W Filter Control SMSC EMC1428 FUNCTION Stores the fractional data for External Diode 2 Stores the Beta Compensation circuitry settings for External Diode 1 Stores the Beta Compensation circuitry settings for External Diode 2 Stores the fractional data for the ...
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... Page 28 00h Page 28 00h Page 28 00h Page 28 00h Page 28 00h Page 28 55h Page 31 (85°C) 00h Page 31 (0°C) 00h Page 31 00h Page 31 55h Page 31 (85°C) 00h Page 31 (0°C) 00h Page 31 00h Page 31 55h Page 31 (85°C) SMSC EMC1428 ...
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... Product ID - EMC1428 FEh R Manufacturer ID FFh R Revision SMSC EMC1428 FUNCTION Stores the integer data for the low limit for the External Diode 6 channel Stores the fractional data for the low limit for the External Diode 6 channel Stores the fractional data for the ...
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... DATASHEET Datasheet DEFAULT 00h - - - - 00h 00h - - - - 00h 00h - - - - 00h 00h - - - - 00h 00h - - - - 00h 00h - - - - 00h 00h - - - - 00h 00h - - - - 00h SMSC EMC1428 ...
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... ALERT pin. Bit 3 - LOW - This bit is set when any of the temperature channels drops below its programmed low limit. See the Low Limit Status Register for specific channel information bit will assert the ALERT pin. SMSC EMC1428 Table 5.3 Temperature Data Format BINARY 1000_0000_000b ...
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... Multiple Temperature Sensor with HW Thermal Shutdown & Hottest of Thermal Zones Table 5.5 Configuration Register ALERT - /COMP Section Table 5.6 Conversion Rate Register Rate 30 DATASHEET (Section 5.9). When (Section 5.20 DAVG_ - DIS 4.1.1. Section 4.1.2. In this mode the Table 4.2. Table 4. DEFAULT - CONV[2:0] (4/sec) SMSC EMC1428 Datasheet DEFAULT 00h 06h ...
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... High Limit 0Bh 06h R/W Internal Diode Low Limit 0Ch 07h R/W External Diode 1 High 0Dh Limit High Byte 13h R/W External Diode 1 High Limit Low Byte SMSC EMC1428 Table 5.7 Conversion Rate 0 CONVERSIONS / SECOND Table 5.8. Table 5.9 Temperature Limit Registers Sign ...
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... Sign Sign DATASHEET Datasheet DEFAULT 00h (0° 00h 55h (85° 00h (0° 00h - - - 00h 55h (85° 00h (0° 00h - - - 00h 55h (85° 00h (0°C) SMSC EMC1428 ...
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... Limit High Byte 5Ah R/W External Diode 6 High Limit Low Byte 5Bh R/W External Diode 6 Low Limit Low Byte 5Ch R/W External Diode 7 High Limit High Byte 5Dh R/W External Diode 7 Low Limit High Byte SMSC EMC1428 0.5 0.25 0.125 - - 0.5 0.25 0.125 - - Sign Sign ...
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... Sign Sign Sign DATASHEET Datasheet DEFAULT - - - 00h - - - 00h DEFAULT 0Ah (10°C) Section 4.1.2 DEFAULT 55h (85° 55h (85° 55h (85° 55h (85° 55h (85°C) SMSC EMC1428 ...
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... Bit 1 - E1FLT - This bit is set if the External Diode 1 channel reported a diode fault. 5.10 TRIP_SET Reading Register ADDR R/W REGISTER B7 1Ch R TRIP_SET 752.9 Reading The TRIP_SET Reading Register stores the voltage measured on the TRIP_SET pin. The bit weighting represents mV above 0V. SMSC EMC1428 Sign Sign Sign ...
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... SYS Section 5.20 for details on the ExTHERM status bits). Section 5.20 for details on the ITHERM status bit DATASHEET Datasheet DEFAULT E2 E1 INT SYS SYS SYS DEFAULT N/A Table 5.2 for the data format. SMSC EMC1428 00h ...
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... External Diode 1 exceeds its high limit, it will increment the high counter. If, on the next measurement, it experiences a diode fault, the high limit counter will be reset and the diode fault counter will be incremented). SMSC EMC1428 Table 5.16 Channel Interrupt Mask Register B6 ...
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... High Limit minus the THERM Hysteresis value. For example, if the CALRT[2:0] bits are set for 4 consecutive alerts on an EMC1428 device, the high limits are set at 70°C, and none of the channels are masked, then the status bits will be asserted after the following four measurements: 1. Internal Diode reads 71° ...
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... The BETAx[2:0] bits will be automatically updated to indicate the current setting. Bit 2-0 - BETAx[2:0] - These bits always reflect the current beta configuration settings. These bits will be updated automatically and writing to these bits will have no effect. SMSC EMC1428 Table 5.18 Consecutive Alert Settings NUMBER OF CONSECUTIVE OUT OF LIMIT ...
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... If no External diodes are selected then the High Byte Register will Table 5.22 Hottest Temperature Register EXT6 EXT5 EXT4 EXT3 40 DATASHEET Datasheet MINIMUM BETA < 0.08 < 0.111 < 0.176 < 0.29 < 0.48 < 0.9 < 2.33 Disabled DEFAULT 80h - - - - 00h DEFAULT EXT2 EXT1 INT SMSC EMC1428 00h ...
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... Bit 1 - E1HIGH - This bit is set when the External Diode 1 channel meets or exceeds its programmed high limit. Bit 0 - IHIGH - This bit is set when the Internal Diode channel meets or exceeds its programmed high limit. SMSC EMC1428 Table 5.23 High Limit Status Register ...
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... THERM THERM THERM THERM 5.14). If any of these bits are set, then the THERM status bit in the Status Register 42 DATASHEET Datasheet DEFAULT ILOW LOW LOW THERM THERM THERM SMSC EMC1428 00h DEFAULT 00h ...
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... Of” comparison. ‘0’ (default) - The External Diode X channel is not compared during the “Hottest Of” Comparison. ‘1’ - The External Diode X channel temperature data is compared to all other indicated channels during the “Hottest Of” Comparison. SMSC EMC1428 Table 5.26 REC Configuration Register B6 B5 ...
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... The DP2 / DN3 and DN2 / DP3 pins support two anti-parallel diode connections (External Diode 2 and External Diode 3). Revision 0.68 (07-08-08) 1°C Multiple Temperature Sensor with HW Thermal Shutdown & Hottest of Thermal Zones Table 5.28 Channel Configuration Register EXT6_ APD 44 DATASHEET Datasheet DEFAULT EXT4_ EXT2_ - 00h APD APD SMSC EMC1428 ...
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... ID The Manufacturer ID Register holds an 8-bit word that identifies SMSC. 5.27 Revision Register (FFh) ADDR. R/W REGISTER FFh R Revision The Revision register contains an 8 bit word that identifies the die revision. SMSC EMC1428 Table 5.29 Filter Control Register AVG6 AVG5 AVG4 AVG _EN ...
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... Chapter 6 Package Information 6.1 EMC1428 Package Drawing Figure 6.1 16-Pin QFN 4mm x 4mm Package Dimensions Revision 0.68 (07-08-08) 1°C Multiple Temperature Sensor with HW Thermal Shutdown & Hottest of Thermal Zones 46 DATASHEET Datasheet SMSC EMC1428 ...
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... Multiple Temperature Sensor with HW Thermal Shutdown & Hottest of Thermal Zones Datasheet Figure 6.2 16-Pin QFN 4mm x 4mm Package Drawing SMSC EMC1428 47 DATASHEET Revision 0.68 (07-08-08) ...
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... Package Markings 6.2.1 EMC1428-X-AP (16-Pin QFN) All devices will be marked on the first line of the top side with “1428” and “-X”. On they second line, packages are marked with the Lot Number. On the third line, packages are marked with Functional Revision code “B” and the Country Code (CC). ...