LM76-NEVAL National Semiconductor, LM76-NEVAL Datasheet
LM76-NEVAL
Specifications of LM76-NEVAL
Related parts for LM76-NEVAL
LM76-NEVAL Summary of contents
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... Serial Bus interface ■ Separate open-drain outputs for Interrupt and Critical Temperature shutdown ■ Shutdown mode to minimize power consumption ■ LM76s can be connected to a single bus ■ 12-bit + sign output; full-scale reading of over 127°C Key Specifications Temperature Alarm ■ ...
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... Simplified Block Diagram Connection Diagram Ordering Information Order Number Supply Voltage LM76CHM-5 LM76CHMX-5 www.national.com SO-8 LM76 See NS Package Number M08A Temperature Acurracy Range for Accuracy ±0.5°C 25°C 5.0V ±1.0°C −10°C to 45°C ±0.5°C 25°C 5.0V ±1.0°C − ...
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Pin Descriptions Label Pin # Serial Bi-Directional Data Line, Open Drain Output, CMOS SDA 1 Logic Level SCL 2 Serial Bus Clock Input, CMOS Logic Level T_CRIT_A 3 Critical Temperature Alarm, Open Drain Output GND 4 Power Supply Ground INT ...
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... LM76CHM-5 20mA Supply Voltage Range (+V 10mA 6.5V −65°C to +125°C 215°C 220°C 3000V 250V = +5.0 Vdc ±10% for the LM76CHM- +25°C, unless otherwise noted Typical Conditions (Note 8) = +70°C to +100°C = −20°C to +85°C for ± ...
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... Low Level Output Voltage OL T_CRIT_A Output Saturation Voltage T_CRIT_A Delay t Output Fall Time OF SERIAL BUS DIGITAL SWITCHING CHARACTERISTICS Unless otherwise noted, these specifications apply for +V ±10% for the LM76CHM-5, CL (load capacitance) on output lines = 80 pF unless otherwise specified. Boldface limits apply for all other limits ...
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... Note 10: 12 bits + sign, two's complement Note 11: This specification is provided only to indicate how often temperature data is updated. The LM76 can be read at any time without regard to conversion state (and will yield last conversion result conversion is in process it will be interrupted and restarted after the end of the read. ...
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... However if HYST 1.3 SERIAL BUS INTERFACE The LM76 operates as a slave on the Serial Bus, so the SCL line is an input (no clock is generated by the LM76) and the SDA line is a bi-directional serial data line. According to Serial Bus specifications, the LM76 has a 7-bit slave address. The five most significant bits of the slave address are hard wired inside the LM76 and are “ ...
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... Note: Event Interrupt mode is drawn as if the user is reading the part. If the user doesn't read, the outputs would go low and stay that way until the LM76 is read. 1.4 TEMPERATURE DATA FORMAT Temperature data can be read from the Temperature and Set Point registers; and written to the Set Point registers. Tem- ...
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... Master (No Acknowledge is typically used as a signal for the slave that the Master has read its last byte). An inadvertent 8-bit read from a 16-bit register, with the D7 bit low, can cause the LM76 to stop in a state where the SDA line is held low as shown in Figure ...
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... Alternatively, the master can issue clock cycles until SDA goes high, at which time issuing a “Stop” condition will reset the LM76. FIGURE 4. Inadvertent 8-Bit Read from 16-Bit Register where D7 is Zero (“0”) www.national.com 10 10101508 ...
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... D0: Shutdown - When set to 1 the LM76 goes to low power shutdown mode. Power up default of “0”. D1: Interrupt mode - 0 is Comparator Interrupt mode Event Interrupt mode. Power up default of “0”. D2, D3: T_CRIT_A and INT Polarity - 0 is active low active high. Outputs are open-drain. Power up default of “0” ...
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Timing Diagrams Typical 2-Byte Read From Preset Pointer Location Such as Temp or Comparison Registers Typical Pointer Set Followed by Immediate Read for 2-Byte Register such as Temp or Comparison Registers Typical 1-Byte Read from Configuration ...
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Typical Pointer Set Followed by Immediate Read from Configuration Register Configuration Register Write Comparison Register Write FIGURE 6. Timing Diagrams 13 10101512 10101513 10101514 www.national.com ...
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... Note: Event Interrupt mode is drawn as if the user is reading the part. If the user doesn't read, the outputs would go low and stay that way until the LM76 is read. FIGURE 7. Temperature Response Diagram for ACPI Implementation www ...
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... Typical Applications FIGURE 9. ACPI Compatible Terminal Alarm Shutdown. By powering the LM76 from auxiliary output of the power supply, a non-functioning overheated computer can be powered down to preserve as much of the system as possible. FIGURE 8. Typical Application 15 10101516 10101519 www.national.com ...
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... Physical Dimensions 8-Lead (0.150 Wide) Molded Small Outline Package (SOP), JEDEC Order Number LM76CNM-3, LM76CNMX-3, LM76CHM-5 or LM76CHM-5X www.national.com inches (millimeters) unless otherwise noted NS Package Number M08A 16 ...
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Notes 17 www.national.com ...
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