AD693 Production
The AD693 is a monolithic signal conditioning circuit which accepts low-level inputs from a variety of transducers to control a standard 4-20 mA, two-wire...
Datasheet
AD693 on Analog.com

1B22 Obsolete
The 1B22 is an isolated voltage-to-current converter that incorporates transformer isolation to achieve high performance and automated surface mount manufacturing...
Datasheet
1B22 on Analog.com

1B21 Obsolete
The 1B21 is an isolated voltage-to-current converter that incorporates a unique circuit design utilizing transformer-based isolation and automated surface...
Datasheet
1B21 on Analog.com