FM75M8 Fairchild Semiconductor, FM75M8 Datasheet
FM75M8
Specifications of FM75M8
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FM75M8 Summary of contents
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... Computers ■ Automotive Components Application Diagram Programmable Ordering Information Part Number FM75M8x © 2006 Fairchild Semiconductor Corporation FM75 Rev. 1.0.8 Description The FM75 contains a high-precision CMOS temperature sensor, a Delta-Sigma analog-to-digital converter, and a SMBus-compatible serial digital interface. Typical accu- racy is ±2°C over the full temperature range of 40°C to 125° ...
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... Pin Assignments Pin Descriptions Pin # Name 1 SDA 2 SCL GND A0, A1 © 2006 Fairchild Semiconductor Corporation FM75 Rev. 1.0.8 SDA 1 8 SCL 2 7 FM75 GND 4 5 Figure 2. Pin Assignments Direction Input/Output Serial Data. Open drain to I/O-data pin for two-wire interface. Input Serial Clock. Clock for two-wire serial interface. ...
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... This specification only indicates how often temperature information is updated to the temperature register. The FM75 can be read at any time without interrupting the temperature conversion process. 4. Accuracy (expressed in °C) = the difference between the FM75 output temperature and the measured temperature. © 2006 Fairchild Semiconductor Corporation FM75 Rev. 1.0.8 Min. ...
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... DD I Shutdown Current DD-SD I Input Leakage Current IN I Output Sink Current OL I Output Leakage Current LEAK t Output Transition Time F C Input Capacitance IN © 2006 Fairchild Semiconductor Corporation FM75 Rev. 1.0.8 Conditions Min 0 -3mA 3V -1.5mA DD OL Interface Inactive R/W Activity on SDA ...
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... Condition) t SDA HIGH after SCL HIGH SU:STO (Stop Condition) t Time in which a FM75 must be POR operational after a power-on reset SCL t HD:STA SDA Data In Data Out © 2006 Fairchild Semiconductor Corporation FM75 Rev. 1.0.8 Conditions t SCL t SU:DAT t t HD:DAT BUF t t LOW HIGH ...
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... The Over-Limit Signal (OS) output is the alarm output. This signal is an open-drain output and, at power-up, this pin is configured with active-low polarity. © 2006 Fairchild Semiconductor Corporation FM75 Rev. 1.0.8 Table 1. Relationship Between Temperature and Digital Output ...
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... Temperature-to-Digital Conversion OS (Comparator Mode) OS (Interrupt Mode) Figure 4. Thermal Alarm Operation in Comparator and Interrupt Modes © 2006 Fairchild Semiconductor Corporation FM75 Rev. 1.0.8 Interrupt Mode In interrupt mode, the OS output first becomes active after a fault tolerance number of consecutive tempera- ture measurements exceed the value stored in the T OS register (similar to comparator mode) ...
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... All bits in the command register default to zero at power-up. © 2006 Fairchild Semiconductor Corporation FM75 Rev. 1.0.8 All of these registers can be accessed by the user via the digital serial interface at any time (see Serial Interface Operation for instructions) ...
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... LSB = Temperature LSB for 10-bit conversions 11-bit LSB = Temperature LSB for 11-bit conversions 12-bit LSB = Temperature LSB for 12-bit conversions Figure 7. Temperature Register Format © 2006 Fairchild Semiconductor Corporation FM75 Rev. 1.0.8 Configuration Register The configuration register is a one-byte (8-bit) read/write register (see Figure 8) ...
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... T OS thermal alarm. For example, for 9-bit conversions, the trip-point temperature is defined by the nine MSBs of the T register and all remaining bits are ignored. OS © 2006 Fairchild Semiconductor Corporation FM75 Rev. 1.0.8 ) Hysteresis Temperature Register (T OS The T HYST ter that stores the programmable lower trip-point temper- ature for the thermal alarm in two’ ...
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... Following the last byte, a master device sends a “not acknowledge” (NACK) followed by a stop condition. A NACK is indicated by leaving SDA HIGH during the clock after the last byte. © 2006 Fairchild Semiconductor Corporation FM75 Rev. 1.0.8 Slave Address Each slave device on the bus has a unique 7-bit address so the master can identify which device is sending or receiving data ...
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... Start from Address Byte Master Figure 10. Inadvertent 8-Bit Read from 16-Bit Register Where and Forces Output LOW © 2006 Fairchild Semiconductor Corporation FM75 Rev. 1.0.8 Writing All writes must be proceeded by a pointer set, even if the pointer is already pointing to the desired register. ...
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... SDA Address Byte Figure 13. One-byte Read from Configuration Register with Preset Pointer © 2006 Fairchild Semiconductor Corporation FM75 Rev. 1.0.8 Note: This segment of this timing diagram is a generic pointer set cycle that must be followed by either an immediate read cycle or write cycle, as shown in this figure and in figures 10, 11, and 12 ...
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... SCL SDA Address Byte . . . . . . . . Figure 15. Pointer Set Followed by Immediate Read from Configuration Register SCL SDA Address Byte Figure 16. Pointer Set Followed by Immediate Write to the Configuration Register © 2006 Fairchild Semiconductor Corporation FM75 Rev. 1.0 R Ack from Pointer Byte FM75 Ack from ...
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... Mechanical Dimensions Dimensions are in inches (millimeters) unless otherwise noted. Figure 17. Molded Package, Small Outline, 0.15 Wide, 8-Lead (M8) © 2006 Fairchild Semiconductor Corporation FM75 Rev. 1.0.8 15 www.fairchildsemi.com ...
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... Fairchild Semiconductor Corporation FM75 Rev. 1.0.8 16 www.fairchildsemi.com ...