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Analog Devices 1B22ANProgrammable, Isolated Voltage-to-Current Converter Datasheet: http:// /Analog/1B22AN.htmRetail $130: http:// /jsp/displayProduct.jsp?sku=05F9177&CMP=KNC-G10000683&HBX_OU=50&HBX_PK=1B22AN FEATURES Internal Isolated Loop Supply Drives 1000 Load Pin Programmable Inputs: 0 V to +5 V or 0 V to +10 V Pin Programmable Outputs: 4 to 20 mA or 0 to 20 mA High CMV Isolation: 1500 V RMS Normal-Mode Output Protection: 240 V RMS High Accuracy Low Offset Tempco: 300 nA/ C Low Gain Tempco: 50 ppm/ C Low Nonlinearity: 0.02% High CMR: 90 dB min Small Package: 1.0" 2.10" 0.35" Meets IEEE STD 472: CMV Transient Protection (SWC) APPLICATIONS Multichannel Process Control D/A Converter Current Loop Interface Analog Transmitters and Controllers Remote Data Acquisition Systems The 1B22 is an isolated voltage-to-current converter that incorporates transformer isolation to achieve high performance and automated surface mount manufacturing for low cost and increased reliability. Designed for industrial applications, it is especially suited for harsh environments with extremely high common-mode interference. With programmable inputs and outputs, the 1B22 provides an unbeatable combination of versatility and performance in a compact plastic package. Functionally, the V/I converter consists of four basic sections: input conditioning, modulator/demodulator, isolated loop supply and current source (Figure 1). The 1B22 is pin program- mable for 0 V to +5 V or 0 V to +10 V inputs and 0 to 20 mA or 4 to 20 mA outputs using an internal resistor network. It can also be set by an external resistor to accept 0 V to +1 V to 0 V to +10 V inputs. Transformer coupling provides 1500 V rms galvanic isolation between the inputs and the current loop. Nonlinearity is an excellent 0.05% max. Loop power is generated internally through a dc/dc converter and is also isolated from the input side (1500 V rms). Loop compliance voltage is dependent on the voltage supplied to the 1B22, and with VLOOP = 28 V, it is sufficient to drive a 1000 load. The 1B22 is fully specified over 25 C to +85 C and operates over the industrial ( 40 C to +85 C) temperature range. Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of Analog Devices. Programmable, Isolated Voltage-to-Current Converter DESIGN FEATURES AND USER BENEFITS Isolated Loop Power: Internal loop supply completely isolates the loop from the input terminals (1500 V rms) and provides the capability to drive 0 to 1000 loads. This elimi- nates the need for an external dc/dc converter. Ease of Use: The 1B22 offers complete isolated voltage-to- current conversion with minimum external parts required to get a conditioned current signal. No external buffers or drivers are required. High CMV Isolation: The 1B22 features high input to output galvanic isolation to eliminate ground loops and offer protection against damage from transients and fault voltages. The isolation barrier will withstand continuous CMV of 1500 V rms and meets the IEEE Standard for Common-Mode Voltage Transient Pro- tection (STD 472-SWC). Small Size: The 1B22 package size (1.0" 2.1" DIP) makes it an excellent choice in multichannel systems for maximum chan- nel density. The 0.35" height also facilitates applications with limited board clearance. (New analog devices 1B22AN isolated voltage-to-current was posted and is owned by: James Middleton) |
j_middleton@chicagopartsnetwork.com (James Middleton) for more information.
