Alexander Stein | fffd80c | 2011-06-28 15:11:23 +0000 | [diff] [blame] | 1 | Kernel driver lm95245 |
| 2 | ================== |
| 3 | |
| 4 | Supported chips: |
| 5 | * National Semiconductor LM95245 |
| 6 | Addresses scanned: I2C 0x18, 0x19, 0x29, 0x4c, 0x4d |
| 7 | Datasheet: Publicly available at the National Semiconductor website |
| 8 | http://www.national.com/mpf/LM/LM95245.html |
| 9 | |
| 10 | |
| 11 | Author: Alexander Stein <alexander.stein@systec-electronic.com> |
| 12 | |
| 13 | Description |
| 14 | ----------- |
| 15 | |
| 16 | The LM95245 is an 11-bit digital temperature sensor with a 2-wire System |
| 17 | Management Bus (SMBus) interface and TruTherm technology that can monitor |
| 18 | the temperature of a remote diode as well as its own temperature. |
| 19 | The LM95245 can be used to very accurately monitor the temperature of |
| 20 | external devices such as microprocessors. |
| 21 | |
| 22 | All temperature values are given in millidegrees Celsius. Local temperature |
| 23 | is given within a range of -127 to +127.875 degrees. Remote temperatures are |
| 24 | given within a range of -127 to +255 degrees. Resolution depends on |
| 25 | temperature input and range. |
| 26 | |
Guenter Roeck | a41a892 | 2014-02-22 08:17:34 -0800 | [diff] [blame] | 27 | Each sensor has its own critical limit. Additionally, there is a relative |
| 28 | hysteresis value common to both critical limits. To make life easier to |
| 29 | user-space applications, two absolute values are exported, one for each |
| 30 | channel, but these values are of course linked. Only the local hysteresis |
| 31 | can be set from user-space, and the same delta applies to the remote |
| 32 | hysteresis. |
Alexander Stein | fffd80c | 2011-06-28 15:11:23 +0000 | [diff] [blame] | 33 | |
| 34 | The lm95245 driver can change its update interval to a fixed set of values. |
| 35 | It will round up to the next selectable interval. See the datasheet for exact |
| 36 | values. Reading sensor values more often will do no harm, but will return |
| 37 | 'old' values. |