AD694ARZ

AD694 is an integrated circuit dedicated to converting voltage signals into standard industrial 4–20mA loop current. ARZ refers to industrial temperature range and 8-lead narrow SOIC surface mount package, supplied in tape reel packaging for automated SMT mass assembly.

This dedicated current loop transmitter chip converts 0V to 2V input analog voltage into precise 4mA to 20mA loop output current, which is the most widely adopted signal standard for industrial field transmission. The internal circuit contains precision bandgap reference, input buffer amplifier and current output driving stage, requiring only a small number of external passive components to complete signal conversion.

It works on a wide DC supply voltage ranging from 4.5V up to 36V, fully adapting to the 24V DC power supply commonly used in industrial control loops. The output current maintains high stability regardless of changes in loop load resistance within the allowable range, and long-distance cable resistance will not cause obvious transmission errors.

The chip integrates a 2V fixed precision voltage reference, which can be used to supply power to front-end sensors, facilitating the overall circuit design of two-wire industrial transmitters. Zero current and full-scale current can be calibrated simply through external resistors to eliminate assembly errors.

Temperature drift is strictly controlled, so the conversion accuracy stays consistent amid drastic ambient temperature changes. The output stage has short-circuit protection to prevent chip damage when field wiring is mistakenly shorted. No complicated digital configuration is needed, and analog signal conversion can be realized purely through analog hardware connection, with extremely high reliability suitable for harsh industrial scenes.

Encapsulated in tiny 8-pin narrow SOIC plastic package with small footprint, suitable for miniaturized two-wire transmitter PCB layout with limited internal space. Moisture Sensitivity Level is MSL3, all reflow soldering operations need to be finished within 168 hours after opening the vacuum sealed package. Standard tape reel feeding matches automatic placement equipment to realize continuous large-scale electronic production.

Continuous stable operation can be achieved from -40°C to +85°C, adapting to factory production workshops, outdoor pipeline monitoring stations and power equipment sites with strong electromagnetic interference and variable temperatures. Manufactured with lead-free production processes, the component meets global RoHS environmental requirements. The all-analog integrated structure simplifies the hardware design of two-wire industrial transmitters and improves long-term field operation stability.

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