EMC2301 Standard Microsystems Corp., EMC2301 Datasheet
EMC2301
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EMC2301 Summary of contents
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... PRODUCT FEATURES General Description The EMC2301 is an SMBus compliant fan controller with a PWM fan driver. The 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. Each closed loop Fan Speed Control algorithm (FSC) has the capability to detect aging fans and alert the system ...
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... TO HAVE FAILED OF ITS ESSENTIAL PURPOSE, AND WHETHER OR NOT SMSC HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. Revision 1.2 (03-22-10) ORDER NUMBER: PACKAGE 8-pin MSOP (Lead-free One RPM-based fan speed control algorithm RoHS compliant) 2 DATASHEET RPM-Based PWM Fan Controller Datasheet FEATURES www.smsc.com/rohs SMSC EMC2301 ...
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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 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 5.2 Configuration Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 5.3 Fan Status Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 5.3.1 Fan Status - 24h . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 5.3.2 Fan Stall Status - 25h . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 5.3.3 Fan Spin Status - 26h . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 5.3.4 Fan Drive Fail Status - 27h . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 5.4 Fan Interrupt Enable Register SMSC EMC2301 3 DATASHEET Revision 1.2 (03-22-10) ...
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... Fan Drive Fail Band Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 5.17 TACH Target Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 5.18 TACH Reading Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 5.19 Software Lock Register 5.20 Product ID Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 5.21 Manufacturer ID Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38 5.22 Revision Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38 Chapter 6 Typical Operating Curves Chapter 7 Package Drawing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 7.1 EMC2301 Package Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 7.2 Package Markings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42 Chapter 8 Revision History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43 Revision 1.2 (03-22-10) 4 DATASHEET RPM-Based PWM Fan Controller Datasheet SMSC EMC2301 ...
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... RPM-Based PWM Fan Controller Datasheet List of Figures Figure 1.1 EMC2301 Pin Diagram (8 pin MSOP Figure 3.1 SMBus Timing Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Figure 4.1 System Diagram of EMC2301 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Figure 4.2 Spin Up Routine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 Figure 4.3 Ramp Rate Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 Figure 7.1 EMC2301 Package Drawing - 8-Pin MSOP Figure 7.2 EMC2301 Package Markings SMSC EMC2301 5 DATASHEET Revision 1.2 (03-22-10) ...
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... List of Tables Table 1.1 Pin Description for EMC2301 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 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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... RPM-Based PWM Fan Controller Datasheet Chapter 1 Pin Description SMDATA SMCLK VDD GND Figure 1.1 EMC2301 Pin Diagram (8 pin MSOP) PIN NUMBER PIN NAME 1 SMDATA 2 SMCLK 3 VDD 4 GND 5 PWM 6 TACH 7 CLK 8 ALERT# The pin types are described in detail below. All pins labeled with (5V) are 5V tolerant. ...
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... I/O. When it is used as an output open drain and requires a pull-up resistor. This pin is 5V tolerant. Open Drain Digital Output - this pin is used as a digital output open drain and requires a pull-up resistor. This pin is 5V tolerant. 8 DATASHEET RPM-Based PWM Fan Controller Datasheet SMSC EMC2301 ...
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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 EMC2301 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 EMC2301 ...
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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 EMC2301 = 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 EMC2301 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 EMC2301 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 EMC2301 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 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 EMC2301 STOP 0 -> 1 ...
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... The EMC2301 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 EMC2301 has two 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. ...
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... PWM Fan Driver The EMC2301 supports a PWM output driver. The output driver can be configured to operate as an open-drain (default) or push-pull driver and the driver can be configured with normal or inverse polarity. Additionally, the PWM frequencies is programmable with ranges from 9.5Hz to 26kHz in four programmable frequency bands. ...
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... The RPM-based Fan Speed Control Algorithm is disabled upon device power up. The following registers control the algorithm. The EMC2301 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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... 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 EMC2301 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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... Update Time until the target fan drive setting is reached. See Revision 1.2 (03-22-10) 30% through 65% New Target Count Update Time Check TACH Target Count Reached Figure 4.2 Spin Up Routine Figure 4.3. 20 DATASHEET RPM-Based PWM Fan Controller Datasheet Fan Step Algorithm controlled drive SMSC EMC2301 ...
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... Watchdog Timer The EMC2301 contains an internal Watchdog Timer for the fan driver. 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) 22 DATASHEET RPM-Based PWM Fan Controller Datasheet SMSC EMC2301 ...
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... Fan Configuration 33h R/W 2 35h R/W Gain SMSC EMC2301 Table 5.1 EMC2301 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 Stores status bits associated with a ...
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... Table 5.1 EMC2301 Register Set (continued) REGISTER ADDR R/W NAME Fan Spin Up 36h R/W Configuration 37h R/W Fan Max Step Fan Minimum 38h R/W Drive Fan Valid TACH 39h R/W Count Fan Drive Fail 3Ah R/W Band Low Byte Fan Drive Fail 3Bh R/W Band High Byte TACH Target Low ...
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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 EMC2301 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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... This may be due to an aging fan or invalid programming. Revision 1.2 (03-22-10) Table 5.3 Fan Status Registers (continued Section 4.8). Section 4.4.2 and Section 26 DATASHEET RPM-Based PWM Fan Controller Datasheet FAN_ - - - SPIN - DRIVE_ - - FAIL Section 4.6). This 5.12). This bit is cleared upon a read if the SMSC EMC2301 DEFAULT 00h 00h ...
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... PWM Output Config - 2Bh Bit 0 - PWM_OT - Determines the output type of the PWM driver. ‘0’ (default) - The PWM output is configured as an open drain output. ‘1’ - The PWM output is configured as a push-pull output. SMSC EMC2301 Table 5.4 Fan Interrupt Enable Register B6 B5 ...
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... Equation ⎛ ⎞ VALUE × -------------------- - = 100% ⎝ ⎠ 255 28 DATASHEET RPM-Based PWM Fan Controller Datasheet PWM_ PWM_ - - BASE BASE _1 _0 BASE FREQUENCY 26.00kHz (default) 19.531kHz 4,882Hz 2,441Hz DEFAULT [1]. [1] SMSC EMC2301 DEFAULT 00h 00h ...
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... Increasing the number of edges measured with respect to the number of poles of the fan will cause the TACH Reading registers to indicate a fan speed that is higher or lower than the actual speed. In SMSC EMC2301 Table 5.9 PWM Divide Register B7 ...
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... GLITCH_ - DER_OPT [1:0] RRC EN 30 DATASHEET RPM-Based PWM Fan Controller Datasheet Table 5.12 is used as a direct multiplier EFFECTIVE TACH MULTIPLIER (BASED ON 2 POLE FANS) 0.5 1 1.5 2 UPDATE TIME 100ms 200ms 300ms 400ms (default) 500ms 800ms 1200ms 1600ms ERR_RNG[1:0] - SMSC EMC2301 DEFAULT 28h ...
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... The algorithm will continue to monitor the fan speed and calculate necessary drive setting changes based on the error; however, these changes are ignored. ERR_RNG[1: SMSC EMC2301 Table 5.13. Table Table 5.15 Derivative Options derivative options used Basic derivative ...
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... Table 5.18 Gain Decode Table 5.19 Fan Spin Up Configuration Register DRIVE_FAIL_ NOKICK CNT [1:0] 32 DATASHEET RPM-Based PWM Fan Controller Datasheet OPERATION 200 RPM DEFAULT GAINI[1:0] GAINP[1:0] RESPECTIVE GAIN FACTOR (default SPINUP_TIME SPIN_LVL[2:0] [1:0] SMSC EMC2301 2Ah DEFAULT 19h ...
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... When the RPM-based Fan Speed Control Algorithm is active, the fan driver will attempt to re-start the fan immediately after the end of the last spin up attempt. The Spin Time is set as shown in SMSC EMC2301 Table 5.20. This circuitry determines whether the fan can be driven to ...
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... Algorithm or by manual settings) exceeds the current fan drive setting by greater than the Fan Step Register setting, the EMC2301 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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... If the measured fan speed does not exceed the target fan speed minus the Fan Drive Fail Band Register settings for a period of time longer than set by the DRIVE_FAIL_CNTx[1:0] bits, then the DRIVE_FAIL status bit will be set and an interrupt generated. SMSC EMC2301 Table 5.25 Valid TACH Count Register B7 ...
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... Table 5.28 TACH Reading Registers 4096 2048 1024 512 256 Conversion. 36 DATASHEET RPM-Based PWM Fan Controller Datasheet DEFAULT - - - F8h 128 64 32 FFh DEFAULT 128 64 32 FFh - - - F8h Equation SMSC EMC2301 ...
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... SWL registers can be updated normally. ‘1’ - all SWL registers cannot be updated and a hard-reset is required to unlock them. 5.20 Product ID Register ADDR R/W REGISTER FDh R Product ID The Product ID Register contains a unique 8-bit word that identifies the product. SMSC EMC2301 ( ) n 1 – × × --------------------------------- - f 60 TACH 1 × ...
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... The Revision Register contains an 8-bit word that identifies the die revision. Revision 1.2 (03-22-10) Table 5.31 Manufacturer ID Register Table 5.32 Revision Register DATASHEET RPM-Based PWM Fan Controller Datasheet DEFAULT DEFAULT 80h SMSC EMC2301 5Dh ...
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... Ambient Temperature (°C) Tachometer Measurement Accuracy vs. Ambient Temperature 1 0.8 0.6 0.4 0.2 0 -0.2 -0.4 -0.6 -0 Temperautre (C) Ambient Temperature (°C) SMSC EMC2301 400 380 360 340 320 300 280 260 240 220 200 2.95 100 150 Tachometer Measurement Accuracy vs. Supply Voltage 1 0.8 0.6 0.4 0.2 0 -0.2 -0.4 -0.6 -0 ...
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... PWM Output 10x Zoom on PWM Output Update Time ends, PWM duty cycle changed 40 DATASHEET RPM-Based PWM Fan Controller Datasheet PWM Frequency vs. Supply Voltage TA = 25C, Base Frequncy = 26Khz 3.05 3.15 3.25 3.35 3.45 3.55 3.65 Supply Voltage (V) FSC Algorithm Spin Up Routine – NoKick Duty Cycle Measured = 50% SMSC EMC2301 ...
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... S EAT IN G PLAN ° - 8° DETAIL "A" SCALE: 3/1 Figure 7.1 EMC2301 Package Drawing - 8-Pin MSOP SMSC EMC2301 c SEE DE TAIL "A" END VIEW 3-D VIEW NOTES: 1. ALL DIMENSIONS ARE IN MILLIMETER. 2. TOLERANCE ON THE TRUE POSITI ON OF THE LEADS I S ± 0.065mm MAXIMUM. ...
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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 EMC2301 Package Markings Revision 1.2 (03-22-10) TOP 1.5pt PB-FREE/GREEN SYMBOL ...
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... Table 2.3, "SMBus Electrical Specifications" Rev. 1.1 (10-12-09) Table 2.2, "Electrical Specifications" Chapter 6, Typical Operating Curves Rev. 1.0 (05-15-09) Initial release of datasheet SMSC EMC2301 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 43 DATASHEET CORRECTION ...