Alameda (MAXREFDES24#): 4-Channel Analog Output - Reference Schematic - Maxim Maxim › Design Support › Technical Documents › Reference Schematics › A/D and D/A Conversion/Sampling Circuits › APP 5839 Keywords: Alameda MAXREFDES24, analog output, programmable logic controllers, industrial control and automation Related Parts REFERENCE SCHEMATIC 5839 ALAMEDA (MAXREFDES24#): 4-CHANNEL ANALOG OUTPUT May 06, 2014 Abstract: The Alameda (MAXREFDES24#) subsystem reference design features four dense, highly accu
More detailed image (JPG) In PLC and DCS systems, analog output currents and voltages provide critical control and actuation functions. The Alameda (MAXREFDES24#) reference design shown in Figure 1 features four flexible and programmable analog outputs that meet industrial control requirements. The MAX5134 lies at the heart of the system. This four-channel, 16-bit, high-accuracy digital-to-analog converter (DAC) provides voltage outputs that drive the inputs of four MAX15500 signal conditioners.
Figure 1. The Alameda subsystem design block diagram.
Alameda connects to Pmod-compatible field-programmable gate array (FPGA)/microcontroller development boards. Alameda requires a 3.3V supply voltage from the Pmod connector and uses the SPI pin assignments as illustrated on the right. The power requirements are shown in Table 1. Note that the external +24V power supply is required for full system operation. The currently supported platforms and ports are shown in Table 2. Table 1.
The firmware is a working example of how to initiate the system and wait for a user's input. A user can select the output mode and type in the DAC input codes. The simple process flow is shown in Figure 2. The firmware is written in C using the Xilinx software development kit (SDK) tool, which is based on the EclipseTM open source standard. Custom Alameda-specific design functions were created utilizing the standard Xilinx XSpi core version 3.03a.
National Instruments GPIB card and cable Thermonics T-2800 precision temperature forcing system Perl script for controlling the FPGA development kit and measurement equipment Windows PC INL, DNL, and TUE are the most important specifications for PLC and other process control systems. The MAX15500 is highly flexible and configurable to meet the needs of various applications. The data was taken at +25°C.
Figure 5. Output error for -10V to +10V output range, with 20% overrange. Measurements of DNL, INL, and TUE for the 0 to 10V voltage output mode, with 20% overrange are shown in Figure 6, Figure 7, and Figure 8, respectively. Figure 6. DNL for 0 to 10V output range, with 20% overrange. Figure 7. INL for 0 to 10V output range, with 20% overrange.
Figure 8. Output error for 0 to 10V output range, with 20% overrange. Measurements of DNL, INL, and TUE for the -20mA to +20mA current output mode, with 20% overrange are shown in Figure 9, Figure 10, and Figure 11, respectively. Figure 9. DNL for -20mA to +20mA output range, with 20% overrange. Figure 10. INL for -20mA to +20mA output range, with 20% overrange.
Figure 11. Output error for -20mA to +20mA output range, with 20% overrange. Measurements of DNL, INL, and TUE for the 0 to 20mA current output mode, with 20% overrange are shown in Figure 12, Figure 13, and Figure 14, respectively. Figure 12. DNL for 0 to 20mA output range, with 20% overrange. Figure 13. INL for 0 to 20mA output range, with 20% overrange.
Figure 14. Output error for 0 to 20mA output range, with 20% overrange. All Design Files Download All Design Files Hardware Files Schematic Bill of materials (BOM) PCB layout PCB Gerber PCB CAD (PADS 9.0) Firmware Files LX9 Platform (Spartan-6) ZedBoard Platform (Zynq-7000) Related Parts MAX14850 MAX15500 MAX1659 MAX17498B MAX5134 MAX6126 Six-Channel Digital Isolator Free Samples Industrial Analog Current/Voltage Output Conditioners Free Samples 350mA, 16.
APP 5839: May 06, 2014 REFERENCE SCHEMATIC 5839, AN5839, AN 5839, APP5839, Appnote5839, Appnote 5839 ©Maxim Integrated | Contact Us | Careers | Legal | Privacy | Site Map | Follow Us: ©Maxim Integrated | Contact Us | Careers | Legal | Privacy | Site Map | Follow Us: http://www.maximintegrated.com/en/app-notes/index.
