Lab_DEHDL_AMS_Flow

1 Design Entry HDL – AMS Simulator Flow Design Entry HDL and AMS Simulator are tightly integrated providing a seamless flow to the process of creating a design, configuring simulation settings, and then simulating the design. With the farther integration of Advanced Analysis capabilities with Design Entry HDL, it is possible to configure and perform advanced simulations, such as Monte Carlo and Sensitivity analysis. The flow is highly interactive, allowing adjustments of parameters and various other design settings to ensure an optimized and efficient design.

This tutorial uses a Switched Mode Power Supply Design as a demo database. The Switched Mode Power Supply Design has been created using Design Entry HDL. The parts used in the design simulate in AMS simulator.

Figure 1-1 shows the design of a Switched Mode Power Supply.

The design contains a hierarchical block pwmcon with a pulse width modulator circuitry controlled by feedback from 18V output. A ferrimeter transformer, designed using Magnetic Parts Editor, is used in the design. A high voltage is switched through the primary winding of the transformer. The secondary winding of the transformer is connected to a rectifier and a filter.

In this tutorial, you will perform the following tasks: 1. Prepare a design for simulation in Design Entry HDL 2. Create parts and associate with models using various tools, such as Model Editor and Magnetic Parts Designer. 3. Specifying simulation settings 4. Run simulation and examine early violations 5. View simulation results 6. Run smoke analysis and edit models 7. Create Measurements and set tolerances 8. Run advanced analysis, such as sensitivity, optimizer, parametric plotter analysis on long run profile, and Monte Carlo analysis

1.1 Preparing the design for simulation in Design Entry HDL Open the design using Design Entry HDL. You will observe the different elements of this design and add parts to the design.

1. Right-click pwmcon and choose Descend or click the Descend button on the toolbar to descend into the part. Observe the verilog_decs parameter as shown in Figure 1-2. This parameter can be passed into the schematic.

2. Right-click on the design and choose Ascend or click the Ascend button on the toolbar to return to the top schematic. Observe the PERIOD parameter on pwmcon, as shown in Figure 1-3.

3. Observe the default parameters, as shown in Figure 1-4. Tolerance parameters define the positive and negative deviation from a component’s nominal value. In order to include a circuit component in a Sensitivity or Monte Carlo analysis, the component must have tolerances for the parameters specified. Smoke parameters are maximum operating conditions for the component. To perform a Smoke analysis on a component, define the smoke parameters for that component. 4. Observe the global parameter, as shown in Figure 1-5. You can use a global parameter to represent a value in any level of a hierarchical design...

5. Enter the command find BEHAV_GEN in the console and then enter next. Observe the BEHAV_GEN part from the function library that is highlighted, as shown in Figure 1-6.

6. Click the Display Attributes button on the toolbar and click on the BEHAV_GEN part to display the Attributes dialog box. Observe the error condition specified as V(OUT)>21 to ensure that V(OUT) the simulation of the design stops if V(OUT) exceeds 21. Also, observe error message specified. Note: You can specify warning conditions by specifying a value for the WARN_COND attribute. In case of warning conditions simulation continues after displaying the specified warning message. 7. Add the part irf840 from the pwrmos library. To do so: a. Choose Component – Add to open the Component Browser. b. Under Browse Libraries, from the Library list select pwrmos and then select irf840 from the Cells list. c. Click the row for the PART NAME IRF840 in the lower pane (Set PPT oprions and make properties (shown below) as Annotatable)

d. Click Add and place the part in the location as shown in Figure 1-7. e. Right-click IRF840 and choose Attributes. f. Select the value IRF840 for ALT_IMPLEMENTATION.

1.2 Create parts and associate with models Design a transformer and add it to the schematic. Launch Magnetic Parts Editor and perform the following steps: 1. Select a component 2. Provide general information 3. Provide electrical information 4. Select a core 5. Select bobbin and winding wire 6. View Results and save the file.