EMC2302 Standard Microsystems Corp., EMC2302 Datasheet
EMC2302
Related parts for EMC2302
EMC2302 Summary of contents
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... PRODUCT FEATURES General Description The EMC2302 is an SMBus compliant fan controller with up to two independently controlled PWM fan drivers. Each fan driver is controlled by a programmable frequency PWM driver and Fan Speed Control algorithm that operates in either a closed loop fashion directly PWM-controlled device. ...
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... ORDER NUMBER: PACKAGE 10-pin MSOP (Lead-free Two RPM-based fan speed control RoHS compliant) algorithms. SMBus address 0101_110(r/w) 10-pin MSOP (Lead-free Two RPM-based fan speed control RoHS compliant) algorithms. SMBus address 0101_111(r/w) 2 DATASHEET Dual RPM-Based PWM Fan Controller Datasheet FEATURES www.smsc.com/rohs SMSC EMC2302 ...
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... Watchdog Timer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 4.8.1 Power Up Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 4.8.2 Continuous Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Chapter 5 Register Set . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 5.1 Register Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 5.1.1 Lock Entries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 5.2 Configuration Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 5.3 Fan Status Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 5.3.1 Fan Status - 24h . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 5.3.2 Fan Stall Status - 25h . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 5.3.3 Fan Spin Status - 26h . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 5.3.4 Fan Drive Fail Status - 27h . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 5.4 Fan Interrupt Enable Register SMSC EMC2302 3 DATASHEET Revision 1.2 (03-22-10) ...
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... Fan Drive Fail Band Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 5.17 TACH Target Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 5.18 TACH Reading Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38 5.19 Software Lock Register 5.20 Product ID Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39 5.21 Manufacturer ID Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39 5.22 Revision Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39 Chapter 6 Typical Operating Curves Chapter 7 Package Drawing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42 7.1 EMC2302 Package Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42 7.2 Package Markings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43 Chapter 8 Revision History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44 Revision 1.2 (03-22-10) Dual RPM-Based PWM Fan Controller 4 DATASHEET Datasheet SMSC EMC2302 ...
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... Dual RPM-Based PWM Fan Controller Datasheet List of Figures Figure 1.1 EMC2302 Pin Diagram (10-Pin MSOP Figure 3.1 SMBus Timing Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Figure 4.1 System Diagram of EMC2302 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Figure 4.2 Spin Up Routine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 Figure 4.3 Ramp Rate Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 Figure 7.1 EMC2302 Package Drawing - 10-Pin MSOP Figure 7.2 EMC2302 Package Markings SMSC EMC2302 5 DATASHEET Revision 1.2 (03-22-10) ...
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... List of Tables Table 1.1 Pin Description for EMC2302 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Table 1.2 Pin Types Table 2.1 Absolute Maximum Ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Table 2.2 Electrical Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Table 2.3 SMBus Electrical Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Table 3.1 Protocol Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Table 3.2 Write Byte Protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Table 3.3 Read Byte Protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 Table 3.4 Send Byte Protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 Table 3.5 Receive Byte Protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 Table 3.6 Block Write Protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 Table 3 ...
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... Dual RPM-Based PWM Fan Controller Datasheet Chapter 1 Pin Description SMDATA SMCLK VDD GND PWM1 Figure 1.1 EMC2302 Pin Diagram (10-Pin MSOP) PIN NUMBER PIN NAME 1 SMDATA 2 SMCLK 3 VDD 4 GND 5 PWM1 6 TACH1 7 PWM2 8 TACH2 SMSC EMC2302 1 2 EMC2302 3 10-MSOP 4 5 Table 1.1 Pin Description for EMC2302 ...
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... Table 1.1 Pin Description for EMC2302 (continued) PIN NUMBER PIN NAME 9 CLK 10 ALERT# The pin types are described in detail below. All pins labeled with (5V) are 5V tolerant. APPLICATION NOTE: For the 5V tolerant pins that have a pull-up resistor, the voltage difference between VDD and the 5V tolerant pad must never be more than 3 ...
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... Note 2.1 For the 5V tolerant pins that have a pull-up resistor, the pull-up voltage must not exceed 3.6V when the EMC2302 is unpowered. 2.1 Electrical Specifications 3.6V -40° ...
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... UNIT CONDITIONS 8 mA current drive current sink ALERT# pin Powered and unpowered uA 0°C < TA < 85°C pull-up voltage < 3.6V = 27°C unless otherwise noted. CONDITIONS 4 mA current sink Powered and unpowered 0°C < TA < 85°C SMSC EMC2302 ...
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... Typical values are CHARACTERISTIC SYMBOL 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 EMC2302 = 27°C unless otherwise noted. A MIN TYP MAX UNITS 1.3 us 0.6 us 300 ns Min = 20+0.1C 300 ns Min = 20+0.1C 400 pF ...
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... Chapter 3 Communications 3.1 System Management Bus Interface Protocol The EMC2302 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 EMC2302 will not stretch the clock signal. ...
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... The SMBus Stop bit is defined as a transition of the SMBus Data line from a logic ‘0’ state to a logic ‘1’ state while the SMBus clock line logic ‘1’ state. When the EMC2302 detects an SMBus Stop bit has been communicating with the SMBus protocol, it will reset its client interface and prepare to receive further communications ...
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... DATASHEET Dual RPM-Based PWM Fan Controller Datasheet Table 3.3. RD ACK Register NACK Data 1 0 XXh 1 Table 3.4. ACK STOP XXh 0 0 -> 1 NACK STOP XXh 1 0 -> 1 REGISTER ACK DATA ACK 0 XXh 0 REGISTER DATA ACK STOP XXh 0 0 -> 1 SMSC EMC2302 STOP 0 -> 1 ...
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... The EMC2302 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). ...
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... Input or Output 4.1 Fan Control Modes of Operation The EMC2302 has two modes of operation for each 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. ...
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... PWM Fan Driver The EMC2302 supports 2 PWM output drivers. Each output driver can be configured to operate as an open-drain (default) or push-pull driver and each driver can be configured with normal or inverse polarity. Additionally, the PWM frequencies are independently programmable with ranges from 9.5Hz to 26kHz in four programmable frequency bands. ...
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... ALERT# pin. The EMC2302 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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... This is useful to detect aging fan conditions (where the fan’s natural maximum speed degrades over time speed setting that is faster than the fan is capable of. The EMC2302 contains circuitry that detects that the programmed fan speed can be reached by the fan. If the target fan speed cannot be reached within a user defined band of tach counts at maximum drive, the DRIVE_FAIL status bits are set and the ALERT# pin is asserted ...
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... After the Spin Up Routine has finished, the EMC2302 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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... Watchdog Timer The EMC2302 contains an internal Watchdog Timer for all fan drivers. The Watchdog timer monitors the SMBus traffic for signs of activity and works in two different modes based upon device operation. These modes are Power Up Operation and Continuous Operation as described below. ...
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... When configured to operate in Continuous Operation, the Watchdog timer will start immediately. The timer will be reset by any access (read or write) to the SMBus register set. The four second Watchdog timer will restart upon completion of SMBus activity. Revision 1.2 (03-22-10) Dual RPM-Based PWM Fan Controller 22 DATASHEET Datasheet SMSC EMC2302 ...
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... Configuration 1 Fan 1 33h R/W Configuration 2 35h R/W Gain 1 SMSC EMC2302 Table 5.1 EMC2302 Register Set FUNCTION Configuration and control Configures the clocking and watchdog functionality Stores the status bits for the RPM- based Fan Speed Control Algorithm Stores status bits associated with a stalled fan ...
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... Table 5.1 EMC2302 Register Set (continued) REGISTER ADDR R/W NAME Fan 1 Spin Up 36h R/W Configuration 37h R/W Fan 1 Max Step Fan 1 Minimum 38h R/W Drive Fan 1 Valid TACH 39h R/W Count Fan 1 Drive Fail 3Ah R/W Band Low Byte Fan 1 Drive Fail 3Bh R/W Band High Byte TACH 1 Target ...
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... ADDR R/W REGISTER 20h R/W Configuration The Configuration Register controls the basic functionality of the EMC2302. The bits are described below. The Configuration Register is software locked. Bit 7 - MASK - Blocks the ALERT# pin from being asserted. SMSC EMC2302 Table 5.1 EMC2302 Register Set (continued) FUNCTION Holds the tachometer reading that ...
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... The CLK pin acts as a clock output and is a push-pull driver. Bit 0 - USE_EXT_CLK - Enables the EMC2302 to use a clock present on the CLK pin as the tachometer clock. If the DR_EXT_CLK bit is set, then this bit is ignored and the device will use the internal oscillator. ‘ ...
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... ALERT# pin to be asserted when an error condition is detected. Bit 1 - FAN2_INT_EN - Allows Fan 2 to assert the ALERT# pin if an error is detected. Bit 0 - FAN1_INT_EN - Allows Fan 1 to assert the ALERT# pin if an error condition is detected. SMSC EMC2302 Section 4.4.2 and Section Table 5 ...
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... Table 5.6 PWM Base Frequency Register Section 5.8). 28 DATASHEET Dual RPM-Based PWM Fan Controller Datasheet POLARITY POLARITY - - PWM2_OT PWM1_OT PWM_ PWM_ PWM_ PWM_ BASE BASE BASE BASE 2_1 2_0 1_1 1_0 SMSC EMC2302 B0 DEFAULT 00h 1 00h DEFAULT 00h ...
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... Fan 1 Divide 41h R/W Fan 2 Divide The PWM Divide registers determine the final frequency of the respective PWM Fan Driver. Each driver base frequency is divided by the value of the respective PWM Divide Register to determine the final SMSC EMC2302 Table 5.7 PWM_BASEx[1:0] Bit Decode Table 5 ...
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... EDGES2[1:0] ALGO2 Table 5.11. Table 5.11 Range Decode REPORTED MINIMUM 1000 (default DATASHEET Dual RPM-Based PWM Fan Controller Datasheet DEFAULT UPDATE1[2:0] 2Bh UPDATE2[2:0] 2Bh TACH COUNT RPM MULTIPLIER 500 1 2 2000 4 4000 8 Table 5.12 is used as a direct multiplier SMSC EMC2302 ...
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... R/W Configuration 2 Fan 2 43h R/W Configuration 2 The Fan Configuration 2 register control the tachometer measurement and advanced features of the RPM-based Fan Speed Control Algorithm. SMSC EMC2302 Table 5.12 Minimum Edges for Fan Rotation MINIMUM TACH EDGES NUMBER OF FAN POLES 3 1 pole 5 2 poles (default) ...
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... Both the basic derivative and the step derivative 1 are used effectively causing the derivative term to have double the effect of the derivative term. Table 5.16 Error Range Options DATASHEET Dual RPM-Based PWM Fan Controller Datasheet 5.15. OPERATION (default) OPERATION 0 RPM (default) 50 RPM 100 RPM 200 RPM SMSC EMC2302 ...
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... The Fan Spin Up Configuration registers control the settings of Spin Up Routine. The Fan Spin Up Configuration registers are software locked. Bit DRIVE_FAIL_CNTx[1:0] - Determines how many update cycles are used for the Drive Fail detection function as shown in the desired tach target. SMSC EMC2302 Table 5.17 Gain Registers ...
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... Drive Fail detection circuitry will count for 32 update 0 periods 64 - the Drive Fail detection circuitry will count for 64 update 1 periods Table 5.21 Spin Level Table 5.22. 34 DATASHEET Dual RPM-Based PWM Fan Controller Datasheet SPIN UP DRIVE LEVEL 30% 35% 40% 45% 50% 55% 60% (default) 65% SMSC EMC2302 ...
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... Algorithm or by manual settings) exceeds the current fan drive setting by greater than the Fan Step Register setting, the EMC2302 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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... DATASHEET Dual RPM-Based PWM Fan Controller Datasheet DEFAULT Section 5.17 DEFAULT 128 64 32 F5h 128 64 32 F5h Equation [2] in Section 5.18 SMSC EMC2302 66h (40%) 66h (40%) ...
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... If one of the algorithms is enabled, setting the TACH Target Register to FFh will disable the fan driver (set the fan drive setting to 0%). Setting the TACH Target to any other value (from a setting of FFh) will cause the algorithm to invoke the Spin Up Routine after which it will function normally. SMSC EMC2302 B7 B6 ...
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... COUNT = TACH Reading Register 38 DATASHEET Dual RPM-Based PWM Fan Controller Datasheet DEFAULT 128 64 32 FFh - - - F8h 128 64 32 FFh - - - F8h Equation where: (typically the tachometer [2] TACH 32.768kHz) (typically 5 for a 2 pole fan) RANGE bits [3] value (in decimal) SMSC EMC2302 ...
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... REGISTER FEh R Manufacturer ID The Manufacturer ID Register contains an 8-bit word that identifies SMSC. 5.22 Revision Register ADDR R/W REGISTER FFh R Revision The Revision Register contains an 8-bit word that identifies the die revision. SMSC EMC2302 Table 5.29 Software Lock Register Table 5.30 Product ID Register ...
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... Ambient Temperature (°C) Temperautre (C) Revision 1.2 (03-22-10) 500 450 400 350 300 250 100 150 2.95 3.05 Tachometer Measurement Accuracy vs. Supply Voltage 1 0.8 0.6 0.4 0.2 0 -0.2 -0.4 -0.6 -0.8 -1 2.95 3.05 100 150 40 DATASHEET Dual RPM-Based PWM Fan Controller Datasheet Supply Current vs. Supply Voltage 3.15 3.25 3.35 3.45 3.55 3.65 Supply Voltage (V) Supply Voltage (V) 3.15 3.25 3.35 3.45 3.55 3.65 Supply Voltage (V) SMSC EMC2302 ...
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... RPM Target from 0 RPM -> 8000 RPM @ time PWM Output 10x Zoom on PWM Output Spin Up Routine Ends – begins normal Duty Cycle operation Measured Update Time ends, PWM duty cycle changed SMSC EMC2302 27000 26800 26600 26400 26200 26000 25800 25600 25400 25200 25000 2 ...
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... SIDE VIEW H C GAUGE PLANE 0.25 SEATING PLANE 0° - 8° L (0.95) DETAIL "A" Figure 7.1 EMC2302 Package Drawing - 10-Pin MSOP Revision 1.2 (03-22-10) REVISION c 4 SEE DETAIL "A" END VIEW NOTES: 3-D VIEW 1. ALL DI MENSIONS ARE IN MILLIMETER. 2. TOLERANCE ON THE TRUE POSITION OF EACH LEAD IS ± 0. MAXIMUM MATERIAL CONDITION. 3. PACKAGE BODY DIMENSIONS " ...
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... Package Markings LINE: 1-T – Device Number LINE: 2-T Version, Revision, Country Code (VRCC) LINE: 1-B – Date Code (YYWW) LINE: 2-B – First 3 Digits of Lot Number LINE: 3-B – Last 4 Digits of Lot Number Figure 7.2 EMC2302 Package Markings SMSC EMC2302 TOP 1.5pt ...
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... Initial release of datasheet Revision 1.2 (03-22-10) Table 8.1 Customer Revision History Updated SMBus Data Hold Time spec Tachometer Setting Accuracy max was changed from +/-3% to +/-2%. Added typical operating curves Added EMC2302-2 for 2nd SMBus address 44 DATASHEET Dual RPM-Based PWM Fan Controller Datasheet CORRECTION SMSC EMC2302 ...