Cadence OrCAD PCB Designer

Figure 9. The Placement dialogue box, showing the components for the one-transistor amplifier.
Transistor Q1 is ready to be placed on the board.
Jargon: refdes is an abbreviation for reference designator, the label for each component on
the schematic drawing. For example, the transistor probably has refdes Q1.
Allegro can place components automatically but it is straightforward to place them manually
for this simple design. See figure 11 on page 24 for guidance on the desired layout.
1. Start by placing the transistor. Click the box next to Q1, which shows its outline in the
Quickview box.
2. Move the cursor out of the Placement box on to your design. The outline of the transistor
is attached to the cursor. Left-click to place it centrally on your board. The outline will
be filled in and a small P for ‘placed’ appears in the Placement box next to the refdes.
If you hover the cursor over the outline of the transistor a popup message Component
Instance “Q1” is shown.
3. We’ll place the connectors for input and output next. Select the boxes for both J1 and J2.
Move the mouse onto the design and a two-pin header for J1 appears on the cursor. Click
somewhere near the left-hand side to place it. Don’t worry about its orientation for now.
4. The outline of J2 now appears automatically; place this on the right-hand side.
5. Next place the four resistors. Put them in the same positions relative to the transistor that
they have on your schematic drawing. This will make the circuit easier to wire! Refer to
your printout to identify each resistor.
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