1. A Time-Digital Converter (TDC)
Harley Cumming
Lisa Kotowski

2. Applications Time of Flight (High-Energy Physics)
Mass Spectroscopy
Medical Devices
Laser Distance Meters (I.E. measuring the speed of light)
Police Radar Guns
Golf Range Finders

3. Theoretical Performance
Measureable Time Scales:
100 ps
1 ns
10 ns
100 ns
Minimize the delay times of each part (within reason of course)

4. Proposed Schematic 150MHz signal-drives FPGA
Signal Generator-> “start” and “stop” pulses
Run through a pair of BNC connectors to drive circuit
Signal passes through (in order)
1 D-flipflop
Voltage Ramp circuit (charges Capacitor)
Stop Signal disables voltage ramp
Secondary 3 D-flipflop (controlled by FPGA)
4 Voltage ramps
Larger capacitor (charges slower)

5. D-flipflops

6. Input Voltage Ramp

7. Operating the TDC
“start” and “stop” signals act as clock signal to the D-flipflops
Drives the D-flip flops-> turn on voltage ramps
Voltage ramps->charge capacitors
Smallest cap. Attached to the input voltage ramp
Capacitors take different times to charge: depending on the amount of charge on each capacitor a measurement of time can be made.
-> FPGA counts/measures the signal

8. Timeline: (Before Next Thrusday)
Finalize circuit design
Order Parts/ Print board
Receive parts/board in mail
Solder the board
Test the board
Done!

9. Possible Challenges/Setback
Time!
Writing the FPGA firmware
Order a PCB and all parts
Solder all the parts to the board
Might not be able to create a PCB
Have a SMT breadboard as backup!
Testing
Might not work according to plan…

10. Questions?