2013-03-11 07:54:19 +08:00
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Kernel driver lm95234
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=====================
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Supported chips:
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2014-04-23 00:34:14 +08:00
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* National Semiconductor / Texas Instruments LM95233
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Addresses scanned: I2C 0x18, 0x2a, 0x2b
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Datasheet: Publicly available at the Texas Instruments website
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http://www.ti.com/product/lm95233
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2013-03-11 07:54:19 +08:00
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* National Semiconductor / Texas Instruments LM95234
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Addresses scanned: I2C 0x18, 0x4d, 0x4e
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Datasheet: Publicly available at the Texas Instruments website
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http://www.ti.com/product/lm95234
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Author: Guenter Roeck <linux@roeck-us.net>
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Description
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-----------
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2014-04-23 00:34:14 +08:00
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LM95233 and LM95234 are 11-bit digital temperature sensors with a 2-wire
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System Management Bus (SMBus) interface and TrueTherm technology
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that can very accurately monitor the temperature of two (LM95233)
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or four (LM95234) remote diodes as well as its own temperature.
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The remote diodes can be external devices such as microprocessors,
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graphics processors or diode-connected 2N3904s. The chip's TruTherm
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2013-03-11 07:54:19 +08:00
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beta compensation technology allows sensing of 90 nm or 65 nm process
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thermal diodes accurately.
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All temperature values are given in millidegrees Celsius. Temperature
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is provided within a range of -127 to +255 degrees (+127.875 degrees for
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the internal sensor). Resolution depends on temperature input and range.
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Each sensor has its own maximum limit, but the hysteresis is common to all
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channels. The hysteresis is configurable with the tem1_max_hyst attribute and
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affects the hysteresis on all channels. The first two external sensors also
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have a critical limit.
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The lm95234 driver can change its update interval to a fixed set of values.
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It will round up to the next selectable interval. See the datasheet for exact
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values. Reading sensor values more often will do no harm, but will return
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'old' values.
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