SPEAR EPICS

Timing Delay and Amplitude Setpoints

The SPEAR timing system uses SRS DG535 delay generators to set delay and trigger parameters using GPIB control. The timing system electrical interlock diagrams are a good reference ( Booster, LINAC, Booster BPM) and also the power supply system manager timing page. Area Hazard Analysis documents are available for each building with timing hardware. The following tables show the current configuration of all delay generators. NOTE: After changing setpoints, users should save settings in saveset location 9. Quick links:

SPEAR Kickers K1, K2, K3 (118-DG1 and 118-DG2)

Kicker Delay from Trigger (nsec) Pulse Width (nsec)
K1 320 730
K2 360 711
K3 320 743

SPEAR Kickers K1 and K2 (118-DG1)

Name Delay (nsec) Thresh/Ampl (V) Offset (V) Term/Load Imped Mode Slope/Polarity Trigger
Trig in - 1.50 - 50 ohm EXT rising Boo Extraction Trig*
T0 out - - - 50 ohm TTL norm 118-DG2 Trig
A out T+320 - - - - norm K1 Delay
B out A+730 - - - - norm K1 Pulse Width
AB out - - - 50 ohm TTL - K1 Trig
C out T+360 - - - - norm K2 Delay
D out C+711 - - - - norm K2 Pulse Width
CD out - - - 50 ohm TTL - K2 Trig
* The trigger in the booster that drives its extraction kicker is, of course, synchronized with both the ejected bucket in the booster and the injected bucket in SPEAR. This synchronization is done in a timing module in the booster. This signal then is buffered to the booster extraction kicker and other diagnostics (BTS-DG1 and BTS-DG2) and into SPEAR to drive a number of synchronization signals.

This signal is further buffered for distribution around SPEAR. The most important of these buffered signals drives the SPEAR injection kickers (118-DG1 and 118-DG2). Other SRSs (117-DG1 and 117-DG2) are dedicated for diagnostics that are also synchronized to injection.

SPEAR Kicker K3 (118-DG2)

Name Delay (nsec) Thresh/Ampl (V) Offset (V) Term/Load Imped Mode Slope/Polarity Trigger
Trig in - 1.00 - 50 ohm EXT rising 118-DG1 Chan T0
T0 out - - - 50 ohm TTL norm SPR-TR1 Digitizer
A out T+320 - - - - norm K3 Delay
B out A+743 - - - - norm K3 Pulse Width
AB out - - - 50 ohm TTL - K3 Trig
C out - - - - - - not assigned
D out - - - - - - not assigned
CD out - - - - - - not assigned

Bucket Select (117-DG1)

Name Delay (usec) Thresh/Ampl (V) Offset (V) Term/Load Imped Mode Slope/Polarity Trigger
Trig in - -0.50 - HIGHZ EXT falling Boo Extraction Trig
T0 out - - - 50 ohm TTL norm -
A out T+35000 - - 50 ohm TTL norm Bucket Select Delay
B out A+50.00 - - 50 ohm TTL norm Bucket Select Pulse Width
AB out - - - 50 ohm TTL - Bucket Select Trig
C out T+2.62 - - 50 ohm TTL norm not assigned
D out C+30.00 - - 50 ohm TTL norm not assigned
CD out - - - 50 ohm NIM - not assigned

SPEAR BPM ECDRs and BTS Toroid 2 (117-DG2)

Name Delay (usec) Thresh/Ampl (V) Offset (V) Term/Load Imped Mode Slope/Polarity Trigger
Trig in - -0.50 - 50 ohm EXT falling Boo Extraction Trig
T0 out - - - 50 ohm TTL norm -
A out T+0.00 - - 50 ohm TTL norm 10Hz BPM ECDR Delay
B out A+0.50 - - 50 ohm TTL norm 10Hz BPM ECDR Pulse Width
AB out - - - 50 ohm TTL - 10Hz BPM ECDR Trigger*
C out T+2.51 - - 50 ohm TTL norm BTS Toroid 2 Delay
D out C+0.10 - - 50 ohm TTL norm BTS Toroid 2 Pulse Width
CD out - - - 50 ohm NIM - B117 BTS Toroid 2 CAEN Module
* The BPM ECDRs (Echotek Digital Receivers) capture data that start at injection. Actually, because of various delays in cable lengths of the signals taking the pulses to the kickers and from the bpms, the ECDRs trigger one or two turns before the beam arrives, allowing capture of the injected turn. The ECDRs are currently used only during machine physics for injection experiments. The timing signal is buffered out by Akre boxes to B116 and B132 and there they are further buffered to the individual ECDRs.

LINAC (LIN-DG1)

Name Delay (usec) Thresh/Ampl (V) Offset (V) Term/Load Imped Mode Slope/Polarity Trigger
Trig in - -0.30 - HIGHZ EXT rising LINAC Inject Trig
T0 out - - - 50 ohm TTL norm -
A out T+3.365 0.40 0.00 50 ohm VAR norm S Band Amp (rear)
B out T+9.898 2.00 0.00 50 ohm VAR norm Modulator (rear)
Linac ACM Triggers (front)
AB out - - - 50 ohm TTL - -
C out T+12.380 0.50 0.00 50 ohm VAR - Inj Kicker 1 (rear)
D out T+12.350 0.50 0.00 50 ohm VAR - Inj Kicker 2 (rear)
CD out - - - 50 ohm TTL - -

LINAC Chopper and Rate (LIN-DG3)

Name Delay (usec) Thresh/Ampl (V) Offset (V) Term/Load Imped Mode Slope/Polarity Trigger
Trig in - -0.30 - 50 ohm ** rising LINAC Inject Trig
T0 out - - - 50 ohm TTL norm -
A out T+13.303 3.00 0.00 50 ohm VAR - Chopper Trigger (rear)
B out T+delay* - - 50 ohm TTL norm Rate
AB out - - - 50 ohm TTL - -
C out T+7.685 - - HIGHZ TTL norm LIN-TR4 PSM Digitizer
D out T+50000 - - 50 ohm TTL invert BTS/LTB BPM ADC
CD out - - - 50 ohm TTL - -
* delay derived from user-specified rate (1,2,5,10 hz)
** External when chopper on, single-shot when chopper off

LTB BPMs and LINAC Pulse Signal Monitor (LIN-DG4)

Name Delay (usec) Thresh/Ampl (V) Offset (V) Term/Load Imped Mode Slope/Polarity Trigger
Trig in - -0.30 - HIGHZ EXT rising LINAC Inject Trig
T0 out - - - HIGHZ TTL norm PSM Scope
A out T+7.818 - - HIGHZ TTL norm LIN-TR1,2,3,5,7 Digitizers
B out T+7.818 - - HIGHZ TTL norm -
AB out - - - HIGHZ TTL - -
C out T+13.439 - - 50 ohm TTL norm LTB BPM X/Y
D out T+7.818 - - 50 ohm TTL norm LTB BPM Sum
(BPM-TR1 Digitizer)
CD out - - - 50 ohm TTL - -

BTS BPMs and BTS Toroid 1 (BTS-DG1)

Name Delay (usec) Thresh/Ampl (V) Offset (V) Term/Load Imped Mode Slope/Polarity Trigger
Trig in - 2.00 - 50 ohm EXT rising Booster Trig
T0 out - - - 50 ohm TTL norm -
A out T+2.00 - - 50 ohm TTL norm BTS Toroid 1 Delay
B out A+0.10 - - 50 ohm TTL norm BTS Toroid 1 Pulse Width
AB out - - - 50 ohm NIM - B140 BTS Toroid 1 CAEN Module
C out T+2.698 - - 50 ohm TTL norm BTS BPM X/Y
D out T+0.892 - - 50 ohm TTL norm BTS BPM Sum
(BPM-TR2 Digitizer)
CD out - - - 50 ohm TTL - -

Booster Kickers, BTS ACMs, and BTS PSM (BTS-DG2)

Name Delay (usec) Thresh/Ampl (V) Offset (V) Term/Load Imped Mode Slope/Polarity Trigger
Trig in - 2.00 - HIGHZ EXT rising Booster Trig
T0 out - - - HIGHZ TTL norm PSM Scope
A out T+1.672 2.0 0.0 50 ohm VAR norm Extraction Kicker 1, BTS ACMs
B out A-0.08 2.0 0.0 50 ohm VAR norm Extraction Kicker 2
AB out - - - 50 ohm TTL - -
C out A+0 - - HIGHZ TTL norm -
D out T+1.25 - - HIGHZ TTL norm LIN-TR6 Digitizer
CD out - - - 50 ohm TTL - -

Booster (BOO-DG1)

Name Delay (usec) Thresh/Ampl (V) Offset (V) Term/Load Imped Mode Slope/Polarity Trigger
Trig in - -0.3 - 50 ohm EXT falling Booster RF Synch Box
T0 out - - - 50 ohm TTL norm -
A out B+91740 - - HIGHZ TTL norm Extraction Septum
B out C+0 - - 50 ohm TTL norm BTS Line
AB out - - - HIGHZ TTL - -
C out T+319.098 -1.6 0.0 50 ohm VAR norm SPEAR Injection
D out C+1 - - HIGHZ TTL norm not assigned
CD out - 2.65 -1.50 50 ohm VAR - not assigned

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Contact (Content): Jim Sebek
Contact (Web Page): Stephanie Allison
Last Modified: Oct 13, 2009