1 / 6

1 horizontal unit = 5 clock cycles = 250 ns

Threshold. Baseline. Reset. Reset. Zoom-in. After detecting rising-edge of comparator, count x (in this case 5) clock pulses, then enable ADC. Assuming 800 kcps , the ADC takes 1.25 μ s to sample. Timing Diagram. 1 horizontal unit = 5 clock cycles = 250 ns. Positive edge-triggered.

marja
Download Presentation

1 horizontal unit = 5 clock cycles = 250 ns

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Threshold Baseline Reset Reset Zoom-in After detecting rising-edge of comparator, count x (in this case 5) clock pulses, then enable ADC Assuming 800 kcps, the ADC takes 1.25 μs to sample Timing Diagram 1 horizontal unit = 5 clock cycles = 250 ns

  2. Positive edge-triggered Count 5 clock cycles before starting ADC Reasons for a Flip-flop • Prevents system from paralyzing • A 2nd data sampling cycle can’t begin in the midst of the 1st • Anything else?

  3. Coincidence/Anti-coincidence Comparator Synchronous Reset Asynchronous Reset Threshold Signal Gain Buffer PIC Mac USB Reset Peak and Hold 10 Block Diagram Peak Voltage ADC Enable

  4. Coincidence/Anti-coincidence Comparator Fast Counter Reset Threshold Signal Gain Buffer PIC Mac USB Reset Peak and Hold 10 Peak Voltage ADC Enable

  5. Group Tasks 4 Knobs 1) Input gain 2) Threshold voltage 3) Time-to-sample 4) Coincidence, anti-coincidence, and no coincidence • Test/fix the detector, pre-amplifier, and shaping-amplifier • Look at the pulses coming from the X-ray source

More Related