The TMP421, TMP422, and TMP423 are remote temperature sensor monitors with a built-in local temperature sensor.
The TMP421, TMP422, and TMP423 are digital temperature sensor ICs offered in a SOT23‑8 package. They provide a built‑in local temperature sensor and one, two, or three remote junction temperature measurement channels, respectively, using a two‑wire SMBus interface.
The document includes features, electrical characteristics, pin configurations, typical performance graphs, mechanical dimensions, and application guidelines for proper remote sensor connection and filtering.
| Operating temperature range | -55 °C to +127 °C |
|---|---|
| Resolution (local sensor) | 12 bits |
| Resolution (remote sensor) | 12 bits |
| Conversion time per channel | 100 ms (typical) |
| SMBus clock frequency | 3.4 MHz |
Both the local and remote temperature sensors have a 12‑bit resolution.