Title: UG crate status
1UG crate status
- TIM CERN 28/10/08
- A.Bartoloni, B.Borgia, F.R.Spada
- INFN Rome
2UG electronics in the TRD gas system
5.6V 12.5V 29V
3UG crate QM qualification and FM acceptance tests
4UG crate QM qualification and FM acceptance
testsSetup
TV / EMC CHAMBER
UG CRATE
GAS SYSTEM SIMULATOR
SLOW CONTROL
TEST STATION
5.6V 12.5V 29V
5UG crate in the thermal vaccum chamber signal
and power cables have a length of 3 m
6UG crate FM acceptance testsTV chamber setup
TV CHAMBER
UG CRATE
GAS SYSTEM SIMULATOR
SLOW CONTROL
5.6V 12.5V 29V
TEST STATION
UGPD power supply
28 V A
28 V B
7UG crate and UGPD power cables 1 m
8UG crate QM qualificationProblems
- 1) QM2 EMC test (UG crate UGPD)
- CE03 at 15 kHz exceeded limit by 3dbInserted
a 450 µF capacitor on 29 V power taps at the
backplane Solved - 2) QM2 EMC test (UG crate UGPD)
- RS03 at 60 V/m, 240 MHZ lost LeCroy
communication between UGSCM and UGPD Removed the
0-Ohm resistor inside the S9011AUGv2 at
UGPDShielded all cables between UG and
UGPD Solved
9EMC test additional capacitor
For the UG-FM, GA followed the method adopted at
CSIST for the TBS board to assemble the
additional capacitors on the 29V line.
10UG crate FM acceptance testsProblems
- 3) FM TVT test (UG crate UGPD)
- at -20 lost of LeCroy communication between
UGSCM and UG boards - rate of 20
- not observed at 50 C in TVT
- not observed at ESS test at -20 C without UGPD
- observed either with UG-FM or with UG-QM2
electronics
11Findings and corrections
- LeCroy errors depends crucially from the actual
5.6V power supply value. Commercial power
supplies feed power to UG through 3m cables - ? Nominal 5.6V at power supply source drops to
5.4V at UG backplane. - Raising external power supply to 5.8V, such that
at the backplane the voltage is 5.6V, failure
behaviour is reproduced and is totally consistent
with UGPD supplying power to UG. - Observations and measurements of bus lines,
routing LeCroy commands, showed instability of
the receivers outputs when any card is not
driving the bus. - Such buses are implemented using LVDS technology
and bus signals are routed from one card to
another by controlled impedance strip lines
etched on the backplane card (UGBP). LeCroyBus
data lines pull down resistors, soldered on the
backplane, produce a bias voltage value at the
input of LVDS receivers (SN65LVDS390PW) that
exceed specifications. - We changed the pull down resistors on UG-QM2
backplane, the correct bias is restored. We did
not observed any error at any condition and
temperature.
12LB LVDS data lines before changes
LB LVDS data lines after changes
_at_VCC 5.4V VIC((Vdata)(Vdata-))/2 2.7 V.
_at_5.4V VIC 1.9 V.
_at_5V VIC 2.5 V.
_at_5V VIC 1.8 V.
SN65LVDS390
SN65LVDS390
VCC
VCC
R
R
2K5 O
3K3 O
LVDS_Data-
LVDS_Data-
R
R
100 O/2
100 O/2
LVDS_Data
LVDS_Data
R
R
2K5 O
1K8 O
MAX VIC 2.5 V
GND
GND
13UG FS electronics
- To confirm and verify diagnostics and solution,
we asked to modify, at CERN, the UG-FS
electronics and we took the opportunity to
perform ESS test and TVT test at Terni, in
coincidence with Tracker spare electronics TCS. - Modified UG-FS electronics arrived in Rome August
18th. - ESS test and TVT test started at SERMS, Terni, on
August 20th and ended on September 20th. - ESS test UG-FS commercial power supplies
- TVT test UG-FS UGPD
14UG-FS layout for Terni test
FS
FS
FS
QM2
FS
QM2
B
A
A hot
B cold
A hot
B cold
A hot
B cold
15ESS test post vibration UG commercial PS5.6V
on backplane
16TVT UG UGPD
10K commands side A10K commands side B
17LeCroy commands tests
- The different types of tested commands are
- 142 command types to all 3 modules UGBS,
UGBC, UGFV, with UGSCM/A and UGSCM/B - To check consistency of test output, we sent
100 commands to empty slots or to modules without
power. Failures were - 100/100
- In addition to specific test of LeCroy commands,
we performed standard functionality test on all
modules. Testing all functions with LeCroy
commands, we did not observed any single failure.
18Le Croy Commands Specific Tests Summary
functionality tests
19UG-UGPD bus
UGPD
UG
LeCroy bus cable length 80 cm x
20What next
- Change UG-UGPD bus cable on UG-FS and UG-FM
- Modify bias resistors on UG-FM backplane
- Functionality test on UG-FM and UG-FS
- 1 and 1/2 weeks after receiving cable parts
- ESS test on UG-FM 1 week
- ESS test on UG-FS 1 week