ADT7421ARMZ-RL7 ON Semiconductor, ADT7421ARMZ-RL7 Datasheet
ADT7421ARMZ-RL7
Specifications of ADT7421ARMZ-RL7
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ADT7421ARMZ-RL7 Summary of contents
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ADT7421 Precision Temperature Sensor with Beta Compensation (for <45 nm Geometries) The ADT7421 is a dual−channel digital thermometer and under/overtemperature alarm, intended for use in PCs and thermal management systems pin− and register−compatible with the ADM1032, ADT7461 and ...
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Another feature of the ADT7421 is Series Resistance Cancellation, where (typical) of resistance in series with the temperature monitoring transistor can be automatically cancelled from the temperature result, allowing noise filtering. The combination of Beta cancellation ...
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MAXIMUM RATINGS Positive Supply Voltage ( GND DD D+ D− to GND SCL, SDA, ALERT, THERM Input Current, SDA, THERM2 Input Current, D− ESD Rating, All Pins (Human Body Model) ESD Rating, All Pins (Machine Model) Maximum Junction ...
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ELECTRICAL CHARACTERISTICS Parameter Power Supply Supply Voltage Average Operating Supply Current Standby Mode Supply Current Power-On-Reset Threshold Temperature−To−Digital Converter Local Sensor Accuracy Resolution Remote Transistor Sensor Accuracy Resolution Remote Sensor Source Current Conversion Time Maximum Series ...
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CAPACITANCE (pF) Figure 3. Temperature Error vs. D+, D− Capacitance −1 −2 −3 −4 −5 −50 − ...
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Theory of Operation The ADT7421 is a local and remote temperature sensor and over/undertemperature alarm, with the added ability to automatically cancel the effect of beta variations in embedded thermal transistors in small geometry CPU’s. When the ADT7421 is operating ...
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D+ C1 REMOTE SENSING TRANSISTOR D– NOTE: CAPACITOR C1 IS OPTIONAL ONLY NECESSARY IN NOISY ENVIRONMENTS 1000pF MAX. Temperature Measurement Results The results of the local and remote temperature measurements are stored in the local and ...
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The user can switch between measurement ranges at any time. Switching the range likewise switches the data format. The next temperature result following the switching is reported back to the register in the new format. However, the contents of the ...
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Table 4. Conversion Rate Register Codes Code Conversion/Second 0x00 0.0625 0x01 0.125 0x02 0.25 0x03 0.5 0x04 1 0x05 2 0x06 4 (Default) 0x07 5 0x08 10 0x09 20 0x0A 36 0x0B to 0xFF Reserved Limit Registers The ADT7421 has ...
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Offset Register Offset errors can be introduced into the remote temperature measurement by clock noise or when the thermal transistor is located away from the hot spot. To achieve the specified accuracy on this channel, these offsets must be removed. ...
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Table 8. List of Registers Read Address Write Address (Hex) (Hex) Not Applicable Not Applicable 00 Not Applicable 01 Not Applicable 02 Not Applicable Not Applicable 0F 10 ...
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When all data bytes have been read or written, stop conditions are established. In write mode, the master pulls the data line high during the ...
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When reading data from a register there are two possibilities. • If the address pointer register value of the ADT7421 is unknown or not the desired value first necessary to set it to the correct value before data ...
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The ADT7421 Interrupt System The ADT7421 has two interrupt outputs, ALERT and THERM. Both have different functions and behavior. ALERT is maskable and responds to violations of software programmed temperature limits or an open−circuit fault on the external transistor. THERM ...
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When the THERM2 limit is exceeded, the THERM2 signal asserts low. • If the temperature continues to increase and exceeds the THERM limit, the THERM output asserts low. • The THERM output de−asserts (goes high) when the temperature falls ...
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Provide a ground plane under the tracks, if possible. GND D+ D– GND Figure 16. Typical Arrangement of Signal Tracks • Try to minimize the number of ...
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Table 11. Configuration Register; Read Address 0x03, Write Address 0x09 Bit Mnemonic Read/Write 7 Mask R/W 6 Run/STOP R/W 5 ALERT/THERM2 R/W 4 BETA Enable R/W 3 Reserved Read only 2 Temperature R/W Range Select 1 Reserved Read only 0 ...
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... Package Type ADT7421ARZ-REEL 8-Lead SOIC_N ADT7421ARZ-REEL7 8-Lead SOIC_N ADT7421ARMZ-REEL 8-Lead MSOP ADT7421ARMZ-RL7 8-Lead MSOP ADT7421ARMZ-2RL 8-Lead MSOP ADT7421ARMZ-2RL7 8-Lead MSOP †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. ...
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... G C SEATING PLANE −Z− 0.25 (0.010 *For additional information on our Pb−Free strategy and soldering details, please download the ON Semiconductor Soldering and Mounting Techniques Reference Manual, SOLDERRM/D. PACKAGE DIMENSIONS SOIC−8 NB CASE 751−07 ISSUE 0.10 (0.004 SOLDERING FOOTPRINT* 1 ...
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... A1 8X *For additional information on our Pb−Free strategy and soldering details, please download the ON Semiconductor Soldering and Mounting Techniques Reference Manual, SOLDERRM/D. Protected by US Patents 5,195,827; 5,867,012; 5,982,221; 6,097,239; 6,133,753; 6,169,442; 7,010,440; other patents pending. ON Semiconductor and are registered trademarks of Semiconductor Components Industries, LLC (SCILLC). SCILLC reserves the right to make changes without further notice to any products herein ...