ADT7468ARQ ON Semiconductor, ADT7468ARQ Datasheet
ADT7468ARQ
Specifications of ADT7468ARQ
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ADT7468ARQ Summary of contents
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VID5 VID4 ACOUSTIC VID3 ENHANCEMENT VID2 CONTROL VID1 VID0 AUTOMATIC FAN SPEED PWM1 ACOUSTIC PWM REGISTERS CONTROL ENHANCEMENT AND PWM2 CONTROL CONTROLLERS HF & LF PWM3 DYNAMIC TACH1 CONTROL TACH2 FAN SPEED COUNTER TACH3 TACH4 PERFORMANCE MONITORING THERMAL THERM PROTECTION ...
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ADT7468 TABLE OF CONTENTS ...
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SPECIFICATIONS ADT7468 ...
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ADT7468 LOW SCL t HD; STA SDA t BUF HIGH t t HD; DAT SU; DAT t HD; STA t t SU; STA SU; STO S P ...
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ABSOLUTE MAXIMUM RATINGS ADT7468 ...
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ADT7468 PIN CONFIGURATION AND FUNCTION DESCRIPTIONS SDA PWM1/XTO 24 1 SCL CCP GND +2. +12V /VID5 CC IN VID0 +5V /THERM ADT7468 VID1 VID4 6 19 TOP VIEW ...
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ADT7468 ...
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ADT7468 TYPICAL PERFORMANCE CHARACTERISTICS 0 –10 –20 –30 –40 –50 – 2.2 3.3 CAPACITANCE (nF) 0 –10 –20 –30 –40 –50 –60 –70 –80 –90 –100 CAPACITANCE (nF GND 40 20 ...
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POWER SUPPLY VOLTAGE ( INT ERROR, 250mV –5 –10 INT ERROR, 100mV –15 –20 10 100 1M ...
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ADT7468 PRODUCT DESCRIPTION ...
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ADT7468 FRONT CHASSIS TACH2 FAN PWM3 REAR CHASSIS VID[0:4]/VID[0:5] TACH3 FAN D1+ AMBIENT TEMPERATURE D1– 3.3VSB 5V 12V/VID5 V COMP ADP316x CURRENT VRM CONTROLLER V CORE GND CPU FAN PWM1 TACH1 5(VRM9)/6(VRM10) D2+ D2– THERM PROCHOT CPU SDA SCL SMBALERT ...
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ADT7468 SERIAL BUS INTERFACE 1 SCL SDA START BY MASTER SERIAL BUS ADDRESS BYTE R/W ACK. BY ADT7468 FRAME 1 1 SCL (CONTINUED SDA (CONTINUED) 9 ...
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SCL SDA START BY MASTER FRAME 1 SERIAL BUS ADDRESS BYTE 1 SCL SDA START BY MASTER FRAME 1 SERIAL BUS ADDRESS BYTE System Management Bus Specifications Rev. 2 ...
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ADT7468 SLAVE SLAVE ADDRESS ADDRESS SLAVE DATA ADDRESS DATA ...
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VID CODE MONITORING ADT7468 ...
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ADT7468 ANALOG-TO-DIGITAL CONVERTER 120k 12V IN 20k 30pF 93k 5V IN 47k 30pF 68k 3.3V IN 71k 30pF 45k 2.5V IN 94k 30pF 17.5k V CCP 52.5k 35pF MUX ...
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ADT7468 ...
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ADT7468 × × BIAS REMOTE SENSING TRANSISTOR D+ LPF D– 65kHz C V OUT+ TO ADC V OUT– ...
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R C 100 REMOTE TEMPERATURE 1nF SENSOR 100 n ∆T D+ D– ADT7468 T − f ...
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ADT7468 ADT7468 2N3904 D+ NPN D– ADT7468 D+ 2N3906 D– PNP ...
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THERM LIMIT TEMPERATURE 100% FANS ADT7468 HYSTERESIS (° C) ...
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ADT7468 LIMITS, STATUS REGISTERS, AND INTERRUPTS ...
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HIGH LIMIT TEMPERATURE “STICKY” STATUS BIT TEMP BACK IN LIMIT (STATUS BIT STAYS SET) SMBALERT ADT7468 CLEARED ON READ (TEMP BELOW LIMIT) ...
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ADT7468 HIGH LIMIT TEMPERATURE “STICKY” STATUS BIT TEMP BACK IN LIMIT (STATUS BIT STAYS SET) SMBALERT INTERRUPT MASK BIT SET CLEARED ON READ (TEMP BELOW LIMIT) INTERRUPT MASK BIT CLEARED (SMBALERT REARMED) ...
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T MIN THERM THERM ASSERTED TO LOW AS AN INPUT: FANS DO NOT GO TO 100%, BECAUSE TEMPERATURE IS BELOW T MIN THERM ASSERTED TO LOW AS AN INPUT: FANS DO NOT GO TO 100%, BECAUSE TEMPERATURE IS ABOVE T ...
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ADT7468 2.914s 1.457s 728.32ms THERM LIMIT 364.16ms (REG. 0x7A) 182.08ms 91.04ms 45.52ms 22.76ms (REG. 0x79) (REG. 0x79) (REG. 0x79 COMPARATOR IN OUT STATUS REGISTER ...
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THERM LIMIT +0.25° C THERM LIMIT TEMP THERM ADT7468 MONITORING CYCLE ADT7468 ...
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ADT7468 ACTIVE COOLING 12V 12V 10k 10k TACH/AIN 4.7k 3.3V ADT7468 10k PWM 12V 1N4148 FAN Q1 NDT3055L 12V 12V 10k 10k 12V TACH FAN TACH 4.7k 3.3V ADT7468 665 Q1 PWM MMBT2222 12V 12V 12V, 4-WIRE FAN 10k V ...
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ADT7468 3.3V 3.3V TACH3 1k Q1 PWM3 MMBT3904 2. MMBT2222 10 MMBT2222 3.3V 10k TYPICAL TACH4 +V 3.3V ADT7468 10k TYPICAL 1N4148 5V OR TACH3 12V FAN TACH 3.3V 10k TYPICAL Q1 PWM3 NDT3055L 12V TACH4 Q3 +V ...
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ADT7468 3. ADT7468 12V FAN 10k TYPICAL PWM 0.01 F TACH +V 1N4148 Q1 NDT3055L R SENSE 2 TYPICAL 12V 1N4148 3. PWM Q1 C1 MMBT2222 TACH R3 R4 FOR 3-WIRE ...
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PULL-UP TACH 4.7k OUTPUT TACH TYPICAL ZD1* *CHOOSE ZD1 VOLTAGE APPROXIMATELY 0.8 × 12V FAN PULL-UP TYP R1 <1k OR TACH 10k TOTEM POLE TACH ZD1 OUTPUT ZENER* *CHOOSE ZD1 VOLTAGE APPROXIMATELY 0.8 × ...
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ADT7468 Fan Speed (RPM) Fan TACH Reading Fan 1 TACH Reading RPM f Fan 1 TACH Reading RPM Fan Speed ...
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ADT7468 ...
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ADT7468 Value PWM MIN Value Value Value Value ...
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MISCELLANEOUS FUNCTIONS ADT7468 VID0 VID1 VID2 VID3 VID4 TACH1 TACH2 TACH3 TACH4 PWM2 PWM3 PWM1/XTO ...
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ADT7468 ADT7468 IS POWERED UP HAS THE ADT7468 BEEN ACCESSED BY A VALID Y SMBUS TRANSACTION ABOVE 0.75V? CCP N Y START FAIL-SAFE TIMER HAS THE ADT7468 BEEN ACCESSED BY A VALID Y SMBUS TRANSACTION? N FAIL-SAFE ...
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AUTOMATIC FAN CONTROL OVERVIEW THERMAL CALIBRATION T REMOTE 1 MIN TEMP THERMAL CALIBRATION T LOCAL MIN TEMP THERMAL CALIBRATION T REMOTE 2 MIN TEMP PWM 100% MIN RAMP CONTROL (ACOUSTIC ENHANCEMENT TACHOMETER 1 RANGE MEASUREMENT PWM MIN 100% ...
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ADT7468 VENTS FAN I/O CARDS VENTS POWER I/O CARDS SUPPLY CPU POOR CPU GOOD CPU AIRFLOW AIRFLOW DRIVE FAN BAYS VENTS GOOD VENTING = GOOD AIR EXCHANGE POOR AIR EXCHANGE HEAT SA SINK TIMS THERMAL INTERFACE MATERIAL CTIM INTEGRATED TIMC ...
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T T OPERATING LOW MIN HIGH THERM RANGE POINT ADT7468 TEMPERATURE ...
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ADT7468 PROGRAMMING THE AUTOMATIC FAN SPEED CONTROL LOOP THERMAL CALIBRATION T MIN REMOTE 1 = THERMAL CALIBRATION AMBIENT TEMP T MIN LOCAL = THERMAL CALIBRATION VRM TEMP T MIN REMOTE 2 = CPU TEMP PWM 100% MIN RAMP CONTROL (ACOUSTIC ...
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FRONT CHASSIS FAN TACH2 PWM3 REAR CHASSIS TACH3 FAN AMBIENT D1+ TEMPERATURE D1– 3.3VSB 5V 12V/VID5 V COMP ADP316x CURRENT VRM V CONTROLLER CORE PWM1 TACH1 CPU FAN 5(VRM9)/6(VRM10) VID[0:4]/VID[0.5] D2+ D2– THERM PROCHOT ADT7468 SDA SCL SMBALERT GND ICH ...
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ADT7468 FRONT CHASSIS FAN REAR CHASSIS FAN AMBIENT TEMPERATURE ADP316x VRM CONTROLLER TACH2 PWM1 TACH1 PWM3 5(VRM9)/6(VRM10) VID[0:4]/VID[0.5] TACH3 D2+ D2– THERM PROCHOT D1+ D1– ADT7468 3.3VSB 5V 12V/VID5 SDA SCL V COMP CURRENT V CORE GND CPU FAN CPU ...
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THERMAL CALIBRATION 100 MIN RANGE REMOTE 1 = THERMAL CALIBRATION 100% AMBIENT TEMP MIN RANGE LOCAL = THERMAL CALIBRATION VRM TEMP 100 MIN RANGE REMOTE 2 = CPU TEMP MUX PWM ...
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ADT7468 THERMAL CALIBRATION T MIN THERMAL CALIBRATION REMOTE 2 = CPU TEMP T MIN LOCAL = THERMAL CALIBRATION VRM TEMP T MIN REMOTE 1 = AMBIENT TEMP PWM 100% MIN RAMP CONTROL (ACOUSTIC ENHANCEMENT TACHOMETER 1 RANGE MUX ...
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T MIN THERMAL CALIBRATION 100 MIN RANGE THERMAL CALIBRATION REMOTE 2 = 100% CPU TEMP MUX MIN RANGE LOCAL = THERMAL CALIBRATION VRM TEMP 100 MIN RANGE REMOTE 1 ...
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ADT7468 100% PWM MIN 0% TEMPERATURE T MIN 100% PWM2 MIN PWM1 MIN 0% TEMPERATURE T MIN Value PWM MIN Value Value Value Value fanspeed PWM duty cycle ...
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PWM MAX PWM MIN 0% T TEMPERATURE MIN Value PWM MAX Value Value Value Value T RANGE 100% PWM MIN 0% T TEMPERATURE MIN 100% 50% 33% 0% 30° C 40° MIN ADT7468 ...
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ADT7468 100% 50% 33% 25% 10% 0% 30° C 40° C 45° C 54° MIN T RANGE PWM MIN T T Max DC Min DC MAX MIN T MAX T MIN Max DC Min DC PWM . MIN ...
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T T Max DC Min DC MAX MIN Max DC Min DC T RANGE 100 TEMPERATURE ABOVE T MIN 100 ...
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ADT7468 100 TEMPERATURE ABOVE T 100 ...
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T RANGE 100 MIN THERM THERMAL CALIBRATION 100 MIN RANGE THERMAL CALIBRATION REMOTE 2 = 100% CPU TEMP MUX MIN RANGE LOCAL = THERMAL CALIBRATION VRM TEMP 100 ...
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ADT7468 100 THERMAL CALIBRATION T THERMAL CALIBRATION REMOTE 2 = CPU TEMP T LOCAL = THERMAL CALIBRATION VRM TEMP T REMOTE 1 = AMBIENT TEMP T RANGE T MIN THERM PWM 100% MIN CONTROL (ACOUSTIC ENHANCEMENT ...
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THERMAL CALIBRATION 100 MIN RANGE THERMAL CALIBRATION REMOTE 2 = 100% CPU TEMP MIN RANGE LOCAL = THERMAL CALIBRATION VRM TEMP 100 MIN RANGE REMOTE 1 = AMBIENT TEMP PWM PWM ...
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ADT7468 WAIT n MONITORING CYCLES CURRENT TEMPERATURE MEASUREMENT T1( T1(n) > (OP1 – HYS) OPERATING POINT TEMPERATURE YES OP1 PREVIOUS YES TEMPERATURE IS T1(n) – T1(n – 1) MEASUREMENT 0.25° – T1(n) – ...
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THERM LIMIT HIGH TEMP LIMIT OPERATING POINT HYSTERESIS ACTUAL TEMP T MIN LOW TEMP LIMIT DECREASE HERE DUE TO DECREASE HERE DUE TO SHORT CYCLE ONLY LONG CYCLE ONLY T1(n) – – 0.5° C T1(n) – ...
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ADT7468 THERM LIMIT OPERATING POINT HYSTERESIS ACTUAL TEMP LOW TEMP LIMIT HIGH TEMP LIMIT T T MIN FROM INCREASING PREVENTED MIN ...
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R (° C) TEMP 120 100 80 60 PWM CYCLE (%) TIME (s) 120 R (° C) TEMP 100 80 PWM DUTY CYCLE (%) TIME (s) 140 R (° C) ...
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ADT7468 120 R (° C) TEMP 100 80 60 PWM DUTY CYCLE (%) TIME ( PWM DUTY CYCLE (%) (° TEMP 140 120 100 ...
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ENHANCING SYSTEM ACOUSTICS THERMAL CALIBRATION T MIN THERMAL CALIBRATION REMOTE 2 = CPU TEMP T MIN LOCAL = THERMAL CALIBRATION VRM TEMP T MIN REMOTE 1 = AMBIENT TEMP ACOUSTIC ENHANCEMENT PWM 100% MIN RAMP CONTROL (ACOUSTIC ENHANCEMENT ...
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ADT7468 PWM_OUT 33% DUTY CYCLE 85 170 TIME SLOTS TIME SLOTS PWM OUTPUT (ONE PERIOD) = 255 TIME SLOTS READ TEMPERATURE CALCULATE NEW PWM DUTY CYCLE DECREMENT IS NEW PWM NO PREVIOUS VALUE > PWM VALUE PREVIOUS BY RAMP RATE ...
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REGISTER TABLES ADT7468 ...
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ADT7468 1 4 ...
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ADT7468 ≤ ...
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ADT7468 PROGRAMMING BLOCK DIAGRAM SPEED FAN CYCLE/RELATIVE DUTY PWM ...
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