ADM1028ARQ ON Semiconductor, ADM1028ARQ Datasheet
ADM1028ARQ
Specifications of ADM1028ARQ
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ADM1028ARQ Summary of contents
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FEATURES On-Chip Temperature Sensor External Temperature Measurement with Remote Diode Interrupt and Over-Temperature Outputs Fault-Tolerant Fan Control with Auto Hardware Trip Point Remote Reset and Power-Down Functions LDCM Support System Management Bus (SMBus) Communications Standby Mode to Minimize Power ...
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ADM1028–SPECIFICATIONS Parameter POWER SUPPLY Supply Voltage Supply Current TEMPERATURE-TO-DIGITAL CONVERTER Internal Sensor Accuracy Resolution External Diode Sensor Accuracy Resolution Remote Sensor Source Current ANALOG OUTPUT Output Voltage Range Total Unadjusted Error, TUE Full-Scale Error Zero Error ...
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... V for a falling edge and V = 2.2 V for a rising edge THERMAL CHARACTERISTICS 16-Lead QSOP Package 105∞ Model ADM1028ARQ 0∞C to 100∞ HIGH t t SU; DAT HD; DAT S Figure 1. Serial Bus Timing Diagram –3– ADM1028 Unit Test Conditions kHz ...
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ADM1028 Pin No. Mnemonic FAN_OFF 1 2 GPI AUXRST 3 4 GND 5 V CC3AUX RST 6 R_RST 7 8 FAN_SPD/NTEST_IN 9 D– THERMA/NTEST_OUT 11 THERMB 12 R_OFF 13 INT 14 15 SCL 16 SDA PIN CONFIGURATION FAN_OFF ...
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D+ TO GND –10 –20 – LEAKAGE RESISTANCE – M TPC 1. Temperature Error vs. PC Board Track Resistance ( 250mV p-p IN ...
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ADM1028 100 1k 10k 100k FREQUENCY – Hz TPC 7. Temperature Error vs. Differential-Mode Noise Frequency FUNCTIONAL DESCRIPTION The ADM1028 is a low-cost temperature monitor and fan con- troller for microprocessor-based systems. The temperature of ...
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In READ mode, the master device will override the acknowledge bit by pulling the data line high during the low period before the ninth clock pulse. This is known as No Acknowledge. The master will then take the data ...
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ADM1028 TEMPERATURE MEASUREMENT SYSTEM Internal Temperature Measurement The ADM1028 contains an on-chip bandgap temperature sen- sor. The on-chip ADC performs conversions on the output of this sensor and outputs the temperature data in 8-bit two’s complement format. The format of ...
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For really long distances (up to 100 feet) use shielded twisted- pair such as Belden #8451 microphone cable. Connect the twisted pair to D+ and D– and the shield to GND close to the ADM1028. Leave the remote end ...
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ADM1028 FAULT TOLERANT FAN CONTROL The ADM1028 incorporates a fault tolerant fan control capability that is tied to operation of the THERMA, THERMB outputs. It can override the setting of the analog output and force it to maxi- mum to ...
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INTERRUPT MASKING Any of the bits in the Interrupt Status Register can be masked out by setting the corresponding mask bit in the Interrupt Mask Regis- ter. That interrupt source will then no longer generate an interrupt. However, the bits ...
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ADM1028 GENERAL-PURPOSE LOGIC INPUT (GPI) Pin 2 is used as a general-purpose logic input with 12 V toler- ance. The GPI input may be programmed to be active high or active low by clearing or setting Bit 6 of the ...
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Register Name Address A7–A0 in Hex Value Registers 0x14–0x38 Company ID 0x3E Revision 0x3F Configuration Register 0x40 Interrupt Status Register 0x41 Interrupt Mask Register 0x43 Manufacturer Test 0x44–0x4A Remote Function 0x4B Alert Status 0x4C Fan Speed Ramp Register 0xCO Address ...
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ADM1028 Table V. Register 0x40 Configuration Register Power-On Default <7:0> = 21h Bit Name R/W 0 START Read/Write INT Enable 1 Read/Write 2 Reserved Read Only 3 Programmable Read/Write Once Therm Limit Lock Bit 4 Soft Reset Read/Write FAN_OFF 5 ...
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Table VII. Register 0x43 Interrupt Mask Register. Power-On Default <7:0> = 00h Bit Name 0 Int Temp Error 1 Flag 1 Mask 2 Flag 2 Mask Int THERM 3 4 GPI Mask 5 Ext Temp Error Ext THERM 6 7 ...
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ADM1028 Table X. Register 0xCO Fan Speed Ramp Register. Power-On Default <7:0> = 00h Bit Name 0 Fan Speed Ramp Enable <2:1> Ramp Rate <7:3> Reserved 0.065 0.049 0.010 0.004 COPLANARITY Revision History Location 4/03—Data Sheet changed from REV. A ...