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Guenter Roecke1eb4902013-03-10 16:54:19 -07001Kernel driver lm95234
2=====================
3
4Supported chips:
Guenter Roeckdfcd4c52014-04-22 09:34:14 -07005 * National Semiconductor / Texas Instruments LM95233
6 Addresses scanned: I2C 0x18, 0x2a, 0x2b
7 Datasheet: Publicly available at the Texas Instruments website
8 http://www.ti.com/product/lm95233
Guenter Roecke1eb4902013-03-10 16:54:19 -07009 * National Semiconductor / Texas Instruments LM95234
10 Addresses scanned: I2C 0x18, 0x4d, 0x4e
11 Datasheet: Publicly available at the Texas Instruments website
12 http://www.ti.com/product/lm95234
13
14
15Author: Guenter Roeck <linux@roeck-us.net>
16
17Description
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19
Guenter Roeckdfcd4c52014-04-22 09:34:14 -070020LM95233 and LM95234 are 11-bit digital temperature sensors with a 2-wire
21System Management Bus (SMBus) interface and TrueTherm technology
22that can very accurately monitor the temperature of two (LM95233)
23or four (LM95234) remote diodes as well as its own temperature.
24The remote diodes can be external devices such as microprocessors,
25graphics processors or diode-connected 2N3904s. The chip's TruTherm
Guenter Roecke1eb4902013-03-10 16:54:19 -070026beta compensation technology allows sensing of 90 nm or 65 nm process
27thermal diodes accurately.
28
29All temperature values are given in millidegrees Celsius. Temperature
30is provided within a range of -127 to +255 degrees (+127.875 degrees for
31the internal sensor). Resolution depends on temperature input and range.
32
33Each sensor has its own maximum limit, but the hysteresis is common to all
34channels. The hysteresis is configurable with the tem1_max_hyst attribute and
35affects the hysteresis on all channels. The first two external sensors also
36have a critical limit.
37
38The lm95234 driver can change its update interval to a fixed set of values.
39It will round up to the next selectable interval. See the datasheet for exact
40values. Reading sensor values more often will do no harm, but will return
41'old' values.