| Local sensor accuracy (Max) (+/- C) | 1 |
| Type | Remote |
| Operating temperature range (C) | 0 to 125 |
| Supply voltage (Min) (V) | 3 |
| Interface type | I2C, SMBus |
| Supply voltage (Max) (V) | 3.6 |
| Supply current (Max) (uA) | 1000 |
| Temp resolution (Max) (bits) | 8 |
| Features | ALERT |
| Remote channels (#) | 1 |
| Addresses | 9 |
| Rating | Catalog |
- Directly senses die temperature of remote ICs
- Senses temperature of remote diodes
- SMBus compatible interface, supports SMBus Timeout
- Register readback capability
- 7 bit plus sign temperature data format
- 2 address select lines enable 9 LM84s to be connected to a single bus
Key Specifications
| Supply Voltage | 3.0V - 3.6V |
| Supply Current | 1 mA (max) |
| Local Temperature Accuracy | ±1.0°C (typ) |
| Remote Diode Temperature Accuracy | |
| +60°C to +100°C | ±3°C (max) |
| 0°C to +125°C | ±5°C (max) |
The LM84 is a remote diode temperature sensor, Delta-Sigma analog-to-digital converter, and digital over-temperature detector with an SMBus? interface. The LM84 senses its own temperature as well as the temperature of a target IC with a diode junction, such as a Pentium? II processor or a diode connected 2N3904. A diode junction (semiconductor junction) is required on the target IC's die. A host can query the LM84 at any time to read the temperature of this diode as well as the temperature state of the LM84 itself. A T_CRIT_A# interrupt output becomes active when the temperature is greater than a programmable comparator limit, T_CRIT.
The host can program as well as read back the state of the T_CRIT register. Three state logic inputs allow two pins (ADD0, ADD1) to select up to 9 SMBus address locations for the LM84. The sensor powers up with default thresholds of 127°C for T_CRIT.