ADT7462ACPZ-5RL7 ON Semiconductor, ADT7462ACPZ-5RL7 Datasheet
ADT7462ACPZ-5RL7
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ADT7462ACPZ-500RL7
ADT7462ACPZ-500RL7TR
ADT7462ACPZ-500RL7TR
ADT7462ACPZ-5RL7TR
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ADT7462ACPZ-5RL7 Summary of contents
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ADT7462 Flexible Temperature, Voltage Monitor, and System Fan Controller The ADT7462 is a flexible systems monitor IC, suitable for use in a wide variety of applications. It can monitor temperature three remote locations, as well as its ...
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ADT7462 VID0 TO VID6 PWM REGISTERS PWM1 TO PWM4 FAN2MAX TACH1 TO TACH8 VR_HOT2 VR_HOT1 THERM2 THERM1 THERMAL DIODE INPUTS VOLTAGE INPUTS BAND GAP TEMPERATURE SENSOR ABSOLUTE MAXIMUM RATINGS Parameter Supply Voltage Voltage on +12V Pin Voltage on V Pin ...
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PIN ASSIGNMENT Pin Mnemonic No. 1 VID0/GPIO1/TACH1 2 VID1/GPIO2/TACH2 3 VID2/GPIO3/TACH3 4 VID3/GPIO4/TACH4 GND 7 TACH5/+12V1 8 TACH6/+12V2 9 SCL 10 SDA 11 ADD 12 ALERT 13 PWM4/+3.3V 14 RESET 15 D1+/+2.5V/+1.8V 16 D1−/SCSI_TERM1 17 D2+ ...
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Pin Mnemonic No. 22 TACH8/+12V3 TACH8: Digital Input (Open Drain). Fan tachometer input to measure speed of Fan 8. +12V3: Analog Input. Monitors 12 V Power Supply /+1.5V/+1.8V/+2.5V V CCP1 +1.5V: Monitors 1.5 V analog input. +1.8V: ...
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ELECTRICAL CHARACTERISTICS Parameter Power Supply Supply Voltage Supply Current Temperature−to−Digital Converter Internal Sensor Accuracy A Resolution Remote Sensor Accuracy D (−40°C ≤ T ≤ +125°C) D Resolution Remote Sensor Source Current (Note 3) Series ...
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ELECTRICAL CHARACTERISTICS Parameter OPEN−DRAIN SERIAL BUS OUTPUT (SDA) Output Low Voltage High Level Output Leakage Current SERIAL BUS DIGITAL INPUTS (SDA AND SCL) Input High Voltage Input Low Voltage Hysteresis DIGITAL INPUT ...
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TYPICAL PERFORMANCE CHARACTERISTICS 0.00160 0.00155 0.00150 0.00145 DEV1 0.00140 DEV3 0.00135 0.00130 0.00125 2.9 3.4 3.9 4.4 SUPPLY VOLTAGE (V) Figure 3. Supply Current vs. Supply Voltage 5. 3. –1 –40 ...
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TYPICAL PERFORMANCE CHARACTERISTICS GND –20 –40 – RESISTANCE (MΩ) Figure 9. Remote Temperature Error vs. Resistance (SRC –2 –4 –6 –8 ...
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TYPICAL PERFORMANCE CHARACTERISTICS 0.200 0.198 0.196 POWERUP 0.194 0.192 0.190 0.188 0.186 0.184 STANDBY 0.182 0.180 – TIMEOUT (Seconds) Figure 15. Local Temperature vs. Power−On Reset Timeout 5.0 4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5 0 ...
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Function Description: Easy Configuration Options There are a number of multifunctional pins on the ADT7462 that need to be configured on powerup to suit the desired application. Note that due to the large number of pins that need to be ...
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Configuration Option 2 Configuration Option 2 is used for thermal monitoring and fan control for Processor 1 and Processor dual processor system. It can also monitor one set of VIDs, if required. Features of Configuration Option 2 ...
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Configuration Option 3 Configuration Option 3 is used to monitor all the voltages in the system for Processor 1 and Processor 2. Additional pins can be configured for fan control, VIDs, or GPIOs, as required. Features of Configuration Option 3 ...
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Configuration Option 4 Configuration Option 4 is used to monitor temperature, voltages, and fans for Processor dual processor system. Features of Configuration Option 4 include the following: • One local and two remote temperature channels • Up ...
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Configuration Option 5 Configuration Option 5 is used to monitor temperature, voltages, and fans for Processor dual processor system. Features of Configuration Option 5 include the following: • One local and two remote temperature channels • Up ...
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Serial Bus Interface The ADT7462 is controlled through use of the serial system management bus (SMBus). The ADT7462 is connected to this bus as a slave device, under the control of a master controller. The SMBus interface in the ADT7462 ...
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If the address pointer register is known to be already at the desired address, data can be read from the corresponding data register without first writing to the address pointer register (see Figure 26 possible to read ...
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For the ADT7462, the send byte protocol is used to write a register address to RAM for a subsequent single byte read from the same address. This operation is shown in Figure 27 SLAVE REGISTER S ...
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Configuration 0 register. The block read operation consists of a send byte operation that sends a block read command to the slave, immediately followed by a repeated start and a read operation that reads out ...
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Unfortunately, this technique requires calibration to cancel the effect of the absolute value of V which varies from device to device. The technique used in the ADT7462 is to measure the change in V when the device is ...
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When reading the full temperature value, the LSB should be read first and then the MSB. Reading the LSBs causes the current MSBs to be frozen until they are read. Reading the MSBs only does not cause any register to ...
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Layout Considerations Digital boards can be electrically noisy environments. The ADT7462 measures very small voltages from the remote sensor, so care must be taken to minimize noise induced at the sensor inputs. The following precautions should be taken: • Place ...
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Table 11. Voltage Inputs Pin Voltage Measured 7 +12V1 8 +12V2 13 +3.3V 15 +2.5V / +1.8V 19 +1.25V / +0.9V 21 +5V 22 +12V3 +1.5V / +1.8V / +2.5V CCP1 +1.5V / +1.8V ...
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Voltage Measurement and Limit Registers The corresponding register locations for voltage measurements are listed in Table 13. Each voltage measurement channel has a high and low voltage limit associated with it. The voltage measurements are compared with these limits. The ...
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V BATT 49.5kΩ 3kΩ 3kΩ 4.5pF 82.7kΩ Figure 37. Equivalent V Input Protection Circuit BATT ADC Information Round Robin Both temperature and voltage measurements are analog inputs that are digitized using the on−board ADC. An internal multiplexer switches between the ...
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CPU to ensure that they match within an acceptable range. This acceptable range is programmable in the ADT7462. The VID lines are monitored by the ADT7462, and the VID code is stored in the VID Value ...
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Status and Mask Registers and ALERT Status Registers Each measured temperature and voltage has an associated high and low limit. The measured values are compared with these programmable limits. The results of these comparisons are stored in the status registers. ...
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V 5 ADT7462 12 V FAN 10 kΩ TYPICAL PWM 0.01 mF TACH Figure 39. Driving a 2−Wire Fan Using the ADT7462 with 3−Wire Fans Figure 40 shows the most typical circuit used with a 3−wire ...
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V 10 kΩ TYPICAL TACH7 +V 3.3 V ADT7462 10 kΩ TYPICAL 5.0V or TACH3 TACH 12 V FAN 3 kΩ TYPICAL Q1 PWM3 NDT3055L Figure 42. Interfacing Two Fans in Parallel to a PWM Output Using ...
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TACH information result, every time a fan speed measurement made, the fan must be switched on for a long ...
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The PWM output is pulse stretched until a valid TACH is read on both TACH inputs synchronized to the particular PWM output. If one fan is connected to one PWM output, the PWM output is pulse stretched until the counter ...
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Fan Startup Timeout To prevent false interrupts being generated as a fan spins up (because it is below running speed), the ADT7462 includes a fan startup timeout function. During this time, the ADT7462 looks for two TACH pulses. If two ...
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PWM Duty Cycle Registers Register 0xAA PWM1 Duty Cycle = 0x00 (0% default) Register 0xAB PWM2 Duty Cycle = 0x00 (0% default) Register 0xAC PWM3 Duty Cycle = 0x00 (0% default) Register 0xAD PWM4 Duty Cycle = 0x00 (0% default) ...
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THERMAL CALIBRATION T REMOTE 1 MIN TEMP THERMAL CALIBRATION T LOCAL MIN TEMP THERMAL CALIBRATION T REMOTE 2 MIN TEMP Figure 51. Automatic Fan Control Block Diagram Step 1—Configuring the MUX First, the user needs to decide how many temperature ...
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THERMAL CALIBRATION T MIN REMOTE 1 = THERMAL CALIBRATION AMBIENT TEMP T MIN LOCAL = THERMAL CALIBRATION VRM TEMP T MIN REMOTE 2 = CPU TEMP Figure 52. Assigning Temperature Channels to Fan Channels To overcome fan inertia, the fan ...
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T MIN THERMAL CALIBRATION T MIN THERMAL CALIBRATION REMOTE 2 = CPU TEMP T MIN LOCAL = THERMAL CALIBRATION VRM TEMP T MIN REMOTE 1 = AMBIENT TEMP Step 3—PWM for Each PWM (Fan) Output MIN PWM is ...
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Programming the PWM Registers MIN The PWM registers are 8−bit registers that allow the MIN minimum PWM duty cycle for each output to be configured anywhere from 0% to 100%. This allows the minimum PWM duty cycle to be set ...
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The T or fan control slope is determined by the RANGE following procedure: 1. Determine the maximum operating temperature for that channel (for example, 70°C). 2. Determine experimentally the fan speed (PWM duty cycle value) that does not exceed the ...
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T for different PWM values can be calculated RANGE MIN using Equation (Max DC * Min DC) MAX MIN where (Max DC − Min DC) × T RANGE T value. RANGE Figure 60 shows PWM ...
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Note on 4−Wire Fans The control range for 4−wire fans is much wider than that of 2−wire or 3−wire fans. In many cases, 4−wire fans can start with a PWM drive of as little as 20%. 100 ...
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T RANGE HYSTERESIS 100 MIN Figure 63. How T Relates to Automatic Fan THERM Control Step 7—T for Temperature Channels HYST T is the amount of extra cooling a fan provides after HYST the temperature measured has ...
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VENTS FAN VENTS I/O CARDS POWER I/O CARDS SUPPLY CPU POOR CPU GOOD CPU AIRFLOW AIRFLOW DRIVE FAN BAYS VENTS GOOD VENTING = GOOD AIR EXCHANGE Figure 65. Chassis Airflow Issues • Worst−Case Processor Power Consumption This data sheet maximum ...
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Table 24 provides a brief description of each parameter. Table 24. T Control Loop Parameters MIN Parameter Description If the temperature drops below the T T LOW an error flag is set in a status register and an SMBALERT interrupt ...
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Table 25. Cycle Bit Assignments Short Code Duration Long Cycle Cycle 000 8 cycles 1 sec 16 cycles 001 16 cycles 2 sec 32 cycles 010 32 cycles 4 sec 64 cycles 011 64 cycles 8 sec 128 cycles 100 ...
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When the temperature falls below the operating temperature, T stays the same. Even when the MIN temperature starts to increase slowly, T because the temperature increases at a rate of ≤0.25°C per cycle. THERM LIMIT HIGH TEMP LIMIT OPERATING POINT ...
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Bit 0 (Remote 1 En enables dynamic T the Remote 1 temperature channel. The chosen T is dynamically adjusted based on the current temperature, operating point, and high and low limits for this zone. Bit 0 (Remote 1 ...
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Approaches to System Acoustic Enhancement There are two different approaches to implementing system acoustic enhancement: temperature−centric and fan−centric. The temperature−centric approach involves smoothing transient temperatures as they are measured by a temperature source (for example, Remote 1 temperature). The temperature ...
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A ramp rate of 1 corresponds to one time slot, which is 1/255 of the PWM period. In enhanced acoustics mode, incrementing or decrementing by 1 changes the PWM output by 1/255 × 100%. Step 11—Ramp Rate for Acoustic Enhancement ...
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Figure 79 shows the PWM output response for a ramp rate this instance, the fan takes about 17.6 seconds to reach full running speed. 140 R (5C) TEMP 120 100 80 PWM DUTY CYCLE (%) 60 40 ...
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The freewheeling test procedure is as follows: 1. PWM1 and PWM2 go to full speed, and PWM3 and PWM4 are switched off. 2. After the spin−up time of PWM1 and PWM2 has elapsed, the speed of Fan 1, Fan 2, ...
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Logic 1 whenever the THERM input is asserted low. The THERM state bits in Host Thermal Status Register 2 (0xB9) indicate that a high−to−low transition has taken place on the THERM pin. TEMPERATURE 1005C 905C 805C ...
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When a GPIO pin is configured as an output, the corresponding bit in the GPIO status register becomes read/write. Setting this bit then asserts the GPIO output. (Again, “asserted” can be high or low, depending on the setting of the ...
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Bit 4 (VRD2) of Configuration Register 2 (0x02). There is also an associated mask bit in Register 0x31 to mask the assertion of these inputs from the ALERT output. SCSI_TERM Inputs Pin 16 and Pin 20 can be configured as ...
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PWM3 is switched off by default (because this is a dedicated pin SMBus communication takes place within 4.6 seconds of the V switching on, this PWM drive is driven to full speed. If SMBus communication does take ...
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Register Tables Table 30. Register Map Addr Description R/W Bit 7 0x00 Config 0 R/W SW Reset 0x01 Config 1 R/W RDY 0x02 Config 2 R/W #FP 0x03 Config 3 R/W V_Core_ Low 0x07 TACH R/W T8E Enable 0x08 TACH ...
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Table 30. Register Map Addr Description R/W Bit 7 0x29 PWM2 Min R/W 7 0x2A PWM3 Min R/W 7 PWM4 Min 0x2B R/W 7 0x2C PWM1 to R/W 7 PWM4 Max 0x30 Thermal R/W R3D Mask 1 0x31 Thermal R/W ...
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Table 30. Register Map Addr Description R/W Bit 7 0x50 Local R/W 7 THERM2/ +1.5V1 (ICH) High 0x51 Remote 1 R/W 7 THERM2 Limit 0x52 Remote 2 R/W 7 THERM2 Limit 0x53 Remote 3 R/W 7 THERM2 Limit 0x54 Local/Re- ...
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Table 30. Register Map Addr Description R/W Bit 7 0x6C Pin 26 R/W 7 Voltage High Limit 0x6D +12V1 R/W 7 Low Limit 0x6E +12V2 R/W 7 Low Limit +12V3 0x6F R/W 7 Low Limit 0x70 +3.3V Low R/W 7 ...
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Table 30. Register Map Addr Description R/W Bit 7 0x8B Remote Temp, MSBs, Pin 15 Volt 0x8C Remote Temp, LSBs 0x8D Remote Temp, MSBs 0x8E Remote Temp, LSBs ...
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Table 30. Register Map Addr Description R/W Bit 7 0xA5 TACH6 R 7 MSB/+12V 2 Voltage 0xA6 TACH7 R 7 Value, LSB 0xA7 TACH7 R 7 MSB/+5V Voltage TACH8 0xA8 R 7 Value, LSB 0xA9 TACH8 R 7 MSB/+12V 3 ...
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Table 31. Register 0x00 — Configuration Register 0 Bit Name R/W [5:0] #Bytes Block R/W Read 6 VID Decoder R Reset R/W 1. POR = 0x20, Lock = Y, SW Reset = Y. Table 32. Register 0x01 — ...
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Table 34. Register 0x03 — Configuration Register 3 Bit Name R/W 0 GPIO_En R/W 1 SCL_Timeout R/W 2 SDA_Timeout R/W 3 VID_Threshold R/W 4 THERM_ R/W Threshold 5 CI Reset R/W 6 XOR Tree R/W 7 V_Core_Low R/W 1. POR ...
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Table 37. Register 0x09 — GPIO Configuration Register 1 Bit Name R/W 0 GPIO1_P R/W 1 GPIO1_D R/W 2 GPIO2_P R/W 3 GPIO2_D R/W 4 GPIO3_P R/W 5 GPIO3_D R/W 6 GPIO4_P R/W 7 GPIO4_D R/W 1. POR = 0x00, ...
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Table 40. Register 0x0C — Dynamic T Bit Name R/W [2:0] CYR1 R/W [5:3] CYR2 R/W 6 Control Loop R/W Select 7 Reserved R 1. POR = 0x40, Lock = Y, SW Reset = Y. Table 41. Register 0x0D — ...
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Table 42. Register 0x0E — THERM1 Configuration Register Bit Name R/W 0 THERM1 Timer R/W Enable 1 THERM1_Local R/W 2 THERM1_ R/W Remote 1 3 THERM1_ R/W Remote 2 4 THERM1_ R/W Remote 3 [7:5] Reserved R 1. POR = ...
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Table 45. Register 0x11 — Pin Configuration Register 2 Bit Name R/W [1:0] Pin 23 R/W 2 Pin 22 R/W 3 Pin 21 R/W 4 Pin 19 R/W 5 Pin 15 R/W 6 Pin 13 R/W 7 Pin 8 R/W ...
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Table 48. Register 0x14 — Easy Configuration Options Bit Name R/W 0 Easy Option 1 R/W Select 1 Easy Option 2 R/W Select 2 Easy Option 3 R/W Select 3 Easy Option 4 R/W Select 4 Easy Option 5 R/W ...
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Table 51. Register 0x19 — Voltage Attenuator Configuration 2 Bit Name R/W 0 Attenuator Pin 23 R/W 1 Attenuator Pin 24 R/W 2 Attenuator Pin 25 R/W 3 Reserved R/W 4 Attenuator Pin 28 R/W 5 Attenuator Pin 29 R/W ...
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Table 54. Register 0x1C — Fan Freewheeling Test Bit Name R/W 0 Test Fan 1 R/W 1 Test Fan 2 R/W 2 Test Fan 3 R/W 3 Test Fan 4 R/W 4 Test Fan 5 R/W 5 Test Fan 6 ...
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Table 58. Register 0x21, Register 0x22, Register 0x23, Register 0x24 — PWM1, PWM2, PWM3 and PWM4 Configuration Registers Bit Name R/W [2:0] Spin−Up R/W Timeout 3 SLOW R/W 4 INV R/W [7:5] BHVR R/W Table 59. Register 0x25 — PWM1, ...
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Table 60. Register 0x26 — PWM3, PWM4 Frequency Bit Name R/W 0 Min 3 R/W 1 Min 4 R/W [4:2] Low Freq 3 R/W [7:5] Low Freq 4 R/W 1. POR = 0x90, Lock = Y, SW Reset = Y. ...
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Table 64. Register 0x31 — Thermal Mask Register 2 Bit Name R/W 0 THERM1 % R/W 1 THERM1 Assert R/W 2 THERM1 State R/W 3 THERM2 % R/W 4 THERM2 Assert R/W 5 THERM2 State R/W 6 VRD1_Assert R/W 7 ...
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Table 68. Register 0x35 — Digital Mask Register Bit Name R/W [2:0] Reserved R 3 FAN2MAX R/W 4 SCSI1 R/W 5 SCSI2 R/W 6 VID Comparison R/W 7 Chassis Intrusion R/W 1. POR = 0x38, Lock = N, SW Reset ...
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Table 72. Register 0x3D — Device ID Register Bit Name R/W [7:0] Device POR = 0x62, SW Reset = N. Table 73. Register 0x3E — Company ID Register Bit Name R/W [7:0] Company POR ...
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Table 77. Register 0x55 — Remote 2/Remote 3 Temperature Hysteresis Bit Name R/W [3:0] Remote 3 R/W Hysteresis [7:4] Remote 2 R/W Hysteresis 1. POR = 0x44, Lock = Y, SW Reset = N. Table 78. Offset Registers (Note 1) ...
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Table 82. Register 0x60, Register 61, Register 62, Register 63 — Local, Remote 1, Remote 2, and Remote 3 T /Hysteresis RANGE Bit Name R/W [3:0] Hysteresis R/W [7:4] Range R/W Table 83. Register 0x64 — Operating Point Hysteresis Bit ...
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Table 85. TACH Limit Registers (Note 1) Register Address R/W 0x78 R/W TACH1 limit/VID limit. 0x79 R/W TACH2 limit. 0x7A R/W TACH3 limit. 0x7B R/W TACH4 limit. 0x7C R/W TACH5 limit/+12V1 voltage high limit. 0x7D R/W TACH6 limit/+12V2 voltage high ...
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Table 90. TACH Value Registers (Note 1) Register Address R/W 0x98 R TACH1, LSB. 0x99 R TACH1, MSB. 0x9A R TACH2, LSB. 0x9B R TACH2, MSB. 0x9C R TACH3, LSB. 0x9D R TACH3, MSB. 0x9E R TACH4, LSB. 0x9F R ...
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Table 94. Register 0xB9 — Host Thermal Status Register 2 Register 0xC1 — BMC Thermal Status Register 2 Bit Name R/W 0 THERM1 % R 1 THERM1 Assert R 2 THERM1 State R 3 THERM2 % R 4 THERM2 Assert ...
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Table 97. Register 0xBC — Host Voltage Status Register 2 Register 0xC4 — BMC Voltage Status Register 2 Bit Name R/W [2:0] Reserved R 3 Pin 24 Voltage R 4 Pin 25 Voltage R 5 Pin 26 Voltage R 6 ...
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... Temperature Range ADT7462ACPZ−5RL7 ADT7462ACPZ−R7 −40°C to +125°C ADT7462ACPZ−REEL †For information on tape and reel specifications, including part orientation and tape sizes, please refer to our Tape and Reel Packaging Specifications Brochure, BRD8011/D. *The “Z’’ suffix indicates Pb−Free part. ...
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... C PACKAGE NOTE 3 OUTLINE *For additional information on our Pb−Free strategy and soldering details, please download the ON Semiconductor Soldering and Mounting Techniques Reference Manual, SOLDERRM/D. N. American Technical Support: 800−282−9855 Toll Free USA/Canada Europe, Middle East and Africa Technical Support: Phone: 421 33 790 2910 Japan Customer Focus Center Phone: 81− ...