Lab 1: Simulate and Fabricate

The assignment for Lab 1 is to get a jump start on simulating circuits and doing board layout. Here are the individual steps:

1. Complete the first-day questionnaire.
2. Install DipTrace on your laptop. See the Olin instructions here.
3. Install the Windows version of LTSpice on your laptop. Download here.
4. Get the DipTrace Tutorial PDF file.
5. Complete the schematic and layout tutorial, pages 1 through 79.
6. Complete a transient simulation of the "Astable Flip Flop" in LTSpice. Plot the current in the LEDs over a ten-second period.
7. Complete a second layout of the "Astable Flip Flop" using the following surface-mount parts (on a two-layer board):
   • Transistors: ON Semiconductor MMBT3904LT1G (SOT23 package, double check pin assignments!)
   • Capacitors: 33uF TDK Corp C3216X5R1C336M160AB (1206 package)
   • LEDs: Lite-On LTST-C170GKT (0805 package)
   • Resistors R2 and R3: 680 ohms (0805 package)
   • Resistors R1 and R4: 34 kilohms (0805 package)
   • 9V battery connector (use same through-hole connector)
8. Minimize the size of your PCB layout to save space. Less than two square-inches is the goal.
9. Produce Gerber files for your design and submit them to OSH Park for fabrication.

This assignment is the whole class in a nutshell.

Note that the ground connection isn't strictly necessary, since this circuit is battery powered, but its inclusion will improve the convergence of your LTspice simulation.