RF2TTC module specifications

TTC RECEIVER CRATE

Last updated: 13/12/2006 17:11

11/12/06: the TTC upgrade system test report is available

The TTC receiving crate is part of the project of upgrading the TTC backbone system.

Its task is to replace the TTCmi, receiving the RF timing signals, preparing them for being used by the experiments, and allowing a remote control and monitoring of the main functionalities.

A document summarising the primary specifications of the TTC receiver crate can be found here (28/11/2005). However, more up-to-date information are available on this web site.

Crate description:

Equipment description in experimental areas:

The equipment necessary to receive, convert, clean and transmit the BC and Frev signals will be the same in each experiment and is as described below:

(click on the modules to see the specification of each of them).

The minimum equipment to be installed in each experiment consists of:

One standard VME crate (6U VME64x). The ALICE crate will probably be water cooled due to the ambient magnetic field (200 gauss);
One crate controller (a Single Board Computer type VP110 from Concurrent Technologies is recommended but could be replaced by another type of controller if required by the experiment);
2 AB/RF receiver 6U VME modules, housing 3 optical receivers, complementary to the transmitters previously described. Each module will deliver 3 signals (either BC or Orbit) to the RF2TTC module via SMA connectors. The probable scheme is 3 AB/RF standard receiver modules per experiment (2 receiving the main BC and Frev signals, and one as a spare module);
2 RF2TTC interface boards (one main and one spare).
Some fanout modules for Orbit and BC.

Each experiment will provide a place to install this receiver crate. One complete system will also be installed in the TTC lab in building 4.

Location:

5 receiver crates will be installed. One in each experiment, and one for development and support, in the TTC lab (4-R-029).

Local

ALICE

RB26

ATLAS

USA15, level-1

CMS

USC55

LHCb

UX85

TTClab

4-R-029

An overview of the locations is available here.

Crate Functionalities

As the previously described VME crate, including the RF2TTC module, will replace 3 previous TTCmi minicrates, it has at least to provide the same functionalities.

Compared functionalities:

Functionality
TTCmi
New system

Provided by

Comments

Provided by

Comments

Reception

Optical level adjustment

Optical attenuator

RF attenuator for CMS

And a comparator at the input of the RF2TTC module

Optical reception of encoded BC and Orbit

LHCrx

optoelectrical conversion + amplification

AB/RF Rx

BC and Orbit on separate fibres. Transmitted via SMA connector to the RF2TTC module.

Decoding

LHCrx

-

No decoding required, but a phase adjustment of the orbit to tune the synchronization. Done by RF2TTC module

Internal features

Internal 40.078MHz clock

C. Gen

RF2TTC

QPLL in stand alone mode

Switch between external and internal clock (manual)

C. Gen

RF2TTC

Remotely controlled by a VME register.

Orbit digital phase adjustment (manual)

LHCrx

3564 steps of 25ns

RF2TTC

Remotely adjustable by a VME register. Done in the FPGA

Orbit pulse stretcher to 1us (fixed)

LHCrx

RF2TTC

Remotely adjustable by a VME register. Done in the FPGA

BC cleaning (PLL with VCXO)

VCXO-PLL

BC jitter = 7ps rms ensured by a very stable VCXO

RF2TTC

Done by a QPLL

Out

Orbit output / ECL

RF2TTC

2 outputs types (ECL and NIM)

BC output / ECL

RF2TTC

2 outputs types (ECL and NIM)

Monitoring

Optoelectrical conversion for signal monitoring with a scope (local)

LHCrx

Physical ECL AC coupled output. Needs a separate optical input.

AB/RF Rx

Lemo output on AB/RF module front panel. (NIM?). Scope (local) monitoring.

TTCrx ready (local)

LHCrx

Led

RF2TTC

QPLL lock monitoring and Orbit detection flag. Remotely monitored

Presence of optical signal at a correct power level (local)

Led

AB/RF

Optical power monitored by AB/RF.

Options

Orbit fanout / ECL

TTCcf

optional

TTC Fanout

BC fanout / ECL

TTCff

Optional – typical jitter values at the output = 10ps rms

TTC Fanout

TDM&BM encoding

TDM BM Encoder

optional

TTCex

Optical fanout

TTCmx

optional

TTCex/tx

New Functionalities:

New functionalities

Provided by

BC phase adjustment

RF2TTC

Not necessary in the previous system. Required to ensure a good synchronisation

Automatic clock switch

RF2TTC

Automatic mode to switch at injection and beam dump. Can be disabled by VME access.

Main BC source selection

RF2TTC

Controlled by VME access. Select BC output between BC ring1, BC ring2, BC ref and Internal BC

Main Orbit source selection

RF2TTC

Controlled by VME access. Select Orbit output between Orbit ring1, Orbit ring2,

Clock and Orbit ECL outputs driven by a 25 Ohms line driver.

RF2TTC, Fanout

Last Updated by Sophie BARON on 13/12/2006 17:11

Hit Counter

	Local
ALICE	RB26
ATLAS	USA15, level-1
CMS	USC55
LHCb	UX85
TTClab	4-R-029

	Functionality	TTCmi		New system
		Provided by	Comments	Provided by	Comments
Reception	Optical level adjustment	Optical attenuator		RF attenuator for CMS	And a comparator at the input of the RF2TTC module
	Optical reception of encoded BC and Orbit	LHCrx	optoelectrical conversion + amplification	AB/RF Rx	BC and Orbit on separate fibres. Transmitted via SMA connector to the RF2TTC module.
	Decoding	LHCrx		-	No decoding required, but a phase adjustment of the orbit to tune the synchronization. Done by RF2TTC module
Internal features	Internal 40.078MHz clock	C. Gen		RF2TTC	QPLL in stand alone mode
	Switch between external and internal clock (manual)	C. Gen		RF2TTC	Remotely controlled by a VME register.
	Orbit digital phase adjustment (manual)	LHCrx	3564 steps of 25ns	RF2TTC	Remotely adjustable by a VME register. Done in the FPGA
	Orbit pulse stretcher to 1us (fixed)	LHCrx		RF2TTC	Remotely adjustable by a VME register. Done in the FPGA
	BC cleaning (PLL with VCXO)	VCXO-PLL	BC jitter = 7ps rms ensured by a very stable VCXO	RF2TTC	Done by a QPLL

Out	Orbit output / ECL			RF2TTC	2 outputs types (ECL and NIM)
Out	BC output / ECL			RF2TTC	2 outputs types (ECL and NIM)
Monitoring	Optoelectrical conversion for signal monitoring with a scope (local)	LHCrx	Physical ECL AC coupled output. Needs a separate optical input.	AB/RF Rx	Lemo output on AB/RF module front panel. (NIM?). Scope (local) monitoring.
	TTCrx ready (local)	LHCrx	Led	RF2TTC	QPLL lock monitoring and Orbit detection flag. Remotely monitored
	Presence of optical signal at a correct power level (local)		Led	AB/RF	Optical power monitored by AB/RF.
Options	Orbit fanout / ECL	TTCcf	optional	TTC Fanout
	BC fanout / ECL	TTCff	Optional – typical jitter values at the output = 10ps rms	TTC Fanout
	TDM&BM encoding	TDM BM Encoder	optional	TTCex
	Optical fanout	TTCmx	optional	TTCex/tx

New functionalities	Provided by
BC phase adjustment	RF2TTC	Not necessary in the previous system. Required to ensure a good synchronisation
Automatic clock switch	RF2TTC	Automatic mode to switch at injection and beam dump. Can be disabled by VME access.
Main BC source selection	RF2TTC	Controlled by VME access. Select BC output between BC ring1, BC ring2, BC ref and Internal BC
Main Orbit source selection	RF2TTC	Controlled by VME access. Select Orbit output between Orbit ring1, Orbit ring2,
Clock and Orbit ECL outputs driven by a 25 Ohms line driver.	RF2TTC, Fanout