FPD LAYOUT

- 18 Roman pots with scintillating fiber detectors.

- Each detector with 6 fiber planes and 1 scintillation counter.

- 112 channels per detector readout with 7 MAPMT’s.

TRIGGER ELECTRONICS

Trigger electronics requirements

• 3 AFE boards to read out vertical spectrometers and dipoles

• 2 AFE boards to read out horizontal spectrometers

• 1 Sequencer , 1 VRB, 3 DFE’s

• Transition Patch Panel (TPP): Interface to AFE.

- Decouples tunnel and Platform grounds.

– Shapes FPD signals to operate within dynamic range of AFE.

• FPD SEQUENCER :

FPD signals delayed by long TOF and cables. FPD sequencer delays AFE controls.

Sequencer can handle only two delays. Third delay will be produced in AFE firmware.

Detector Cable delay

TOF Total Delay

A1,P1 236 ns 77 ns 313 ns

A2, P2 471 ns 103 ns 574 ns

D1,D2 444 ns 190 ns 634 ns

FPD Noise at Input of AFE

rms

mean

NOISE ON TPP DIPOLE BOARD

30 30 35

12 12

Noise pattern is the same in every svx

•FPD noise pattern on AFE is due to TPP layout

•Location of GNDA layer is the cause for getting noise on AFE.

TPP layer design:

One channel basic circuit:

TESTS WITH RETROFITTED TPP

FPD STATUS

• Two AFE boards connected right now. One for reading out dipole detectors. Second one has been used for debugging noise issues with TPP board.

• We have found the solution for noise issues. We are working on getting new boards made to resolve this problem.

• Taking data with 45gapN trigger. Few special runs with trigger using own FPD aot’s to TFW.

• Also working on testing DFE at CTS test stand.

• We will have full FPD operational after Tevatron shutdown.