SY11x Two-Wire Voltage to 4-20mA Current Loop Transmitter

 The SY11x series of two-wire passive V/I conversion current loop precision transmitters is a low-cost, passive, two-wire voltage to 4-20mA transmitter IC that serves as a domestic replacement for the XTR115 series chip. It is available in compact form factors (single-in-line package (SIP) with 7 pins, dual-in-line package (DIP) with 8 pins, and surface-mount device (SMD) with 12 pins).It is mainly used in industrial field instruments and sensors for universal current loop simulation of 4mA to 20mA signal transmission and transmission circuits, and can achieve high-precision analog current signal regulation and output current signal limitation functions.This IC can receive voltage signals output from upstream host devices via a downstream current loop power supply method. After V/I conversion, it outputs a standard 4-20 mA two-wire current signal.The built-in voltage regulator (5V) can be used to power external circuits, and the internal voltage reference Vref (2.5V for SY115, 4.096V for SY116, and 3V for SY117) can be used to excite sensors or offset them.The current loop pin (Iret) can detect any current parameter value used in the external circuit to precisely control the output standard 4-20mA current signal.The SY11x is a basic building block for smart sensors that use 4mA to 20mA current transmission and can meet industrial-grade operating temperature ranges from –40°C to +85°C.

   The SY11x series products are designed as low-cost, small-sized standard flame-retardant module packages. The internal circuitry includes a 5V LDO voltage regulator circuit, a precision voltage reference circuit, and a VI conversion circuit. The output circuitry provides a wide supply voltage range (7.5-36VDC), high conversion accuracy, and good linearity.The product is extremely easy to use,customers just need to add a few peripheral components to the product input end to achieve voltage signal distribution for sensors and bridge (weighing) detection circuits that require power distribution, such as voltage sensors and displacement potentiometers. The product is compact and easy to install,The angle displacement and linear displacement sensor resistance signals can be converted into standard 4-20mA analog signals inside the dedicated sensor directly. The full scale and zero point can be adjusted and calibrated by the user through an external multi-turn potentiometer. Users can refer to the typical application circuit diagram when designing.

   The SY11x series products use high-efficiency rear-end power supply technology to achieve precise isolation conversion of voltage signals to standard 4-20 mA signals.It is compatible with various types of instrumentation standard analog input ports (such as PLC, DCS, display control instruments, etc.). The product meets industrial-grade requirements for harsh field environments, including wide temperature ranges, humidity, and vibration.