ds1848 is a dual temperature controlled nonvolatile variable resistor launched by texas instruments. the device consists of two 256-position linear variable resistors, respectively 10kΩ and 50kΩ. it can compensate for bias voltage and current in control applications with the minimum amount of circuitry. ds1848's variable resistor settings are stored in eeprom memory and can be accessed over the industry standard 2-wire serial bus. the value of each variable resistor is determined by a temperature-addressed look-up table, which can assign a unique value to each resistor for every 2°c increase over the -40°c to +95°c range. the output of the digital temperature sensor is also available as a 13-bit, 2's complement format.
The DS1848 integrates two 256‑position linear variable resistors (one 10 kΩ and one 50 kΩ option) with an on‑chip temperature sensor. Resistor settings are stored in 128 bytes of EEPROM and can be accessed via a standard 2‑wire (I²C‑compatible) serial bus. The device operates from 3 V to 5.5 V and supports temperatures from –40 °C to +95 °C.
Programming is performed by writing lookup‑table values for each 2 °C increment, allowing temperature‑compensated bias voltages. The datasheet provides detailed pin assignments, electrical characteristics, timing diagrams, and memory map for both user EEPROM and lookup tables.
| Supply voltage range | 3.0 V to 5.5 V |
|---|---|
| Operating temperature range | -40 °C to +95 °C |
| User EEPROM size | 128 bytes |
| Temperature sensor resolution | 13‑bit 2’s complement |
| SCL clock frequency | Standard mode 100 kHz, Fast mode 400 kHz |
| EEPROM write time | 5 ms to 20 ms |
| Uncompensated temperature coefficient | 850 ppm/°C |
The DS1848 is programmed over a 2‑wire serial interface using SDA and SCL lines.
It operates from –40 °C up to +95 °C.