Siemens SM1223 Digital output, 8DI/8DO, transistor 0.5AProduct Overview The SIMATIC S7 1200 Digital I O Module SM 1223 provides balanced digital signal processing with 8 inputs and 8 transistor outputs. Featuring 24V DC sink source inputs and 0. 5A transistor outputs, this module delivers efficient I O expansion for industrial automation applications requiring moderate density digital interfacing with fast switching transistor outputs. Key Features 8 Digital Inputs + 8 Transistor Outputs: Balanced I O