slide 1

Token Bit Manager for the CMS Pixel Readout

Token Bit Manager for the CMS Pixel Readout

5 November 2003

Edward Bartz(R.Stone)

Rutgers University

CMS Pixel Electronics Systems Review

• Description of the TBM Functions• First Prototype in DMILL• 0.25 m Translation

slide 2

TBM Overview

• Orchestrate the Readout of Several Pixel Chips on a Single Analog Output Link

• Provide a Link Between the Front End Controller and the Pixel Chips For Control Commands

Custom, Mixed Mode, Rad-Hard, Chip Located Near Pixel Readout Chips

slide 3

Dual TBM Chip

Dual TBM Chip

• Two Token Bit Manager’s

– Each TBM Controls one ROC Chain

–8 to 24 ROCs per TBM

• Control Network Hub

– Port addressing for control commands

–6 to 14 Dual TBMs per Control Link

–120 Links in the Detector

~1200 TBMs & 20,000 ROCs

Dual TBMHUB

TBM TBM

Chain of Read Out Chips

ControlCommands

40 MHz Clock

CLK

L1

Analog OutputL1A

Analog Output

Analog Output

Chain of Read Out Chips

slide 4

TBM Functions

• Write header and trailer (2 bit analog encoded digital)– 8 bit Event Number Header– 8 bit Error status word Trailer

• Distribute to Pixel Readout Chips (ROC)– L1 triggers (2 Outputs/TBM)– Clock (2 Outputs/TBM)

• Control readout through token pass

• Stack triggers awaiting token pass– 32 event deep– No readout after 16 deep

L1 Trigger

TBM

ROC ROC ROC

L1CLK Token InToken Out

Analog Output

AnalogOutput

Clock Reset

To Flash ADC

slide 5

• Levels Chosen To Match ROC

• Output Levels Fully Adjustable– Gain Adjustment– Differential Offset Adjustment– Driver Current Adjustment

• Output Driver Identical to ROC

Analog Output

Note: Voltages are referenced to Analog Optical Link input. Levels 4&5 ROC Only

slide 6

TBM Control Features

• Analog Adjustments– Adjust Analog Levels

– Disable Analog Output

• Trigger Control– Inject Any Trigger Type

– Ignore Incoming Triggers

– Disable Trigger Outputs

• Token Passing– Disable Token Passing

– Reset Token Out

• Stack Control– Read Number of Events on Stack

– Read Stack Contents (non-destructively)

• General Control– Switch Readout to 40 MHz or 20 MHz

– Disable TBM Clock

– Reset TBM

slide 7

Control Network Hub

• Up to 32 hubs addressable.

• 5 Ports per hub.– 4 mI2C (40 MHz) external ROCs.

– 1 mI2C (40 MHz) internal TBMs.

• Functions of addressed hub.– Selects addressed port.

– Strips off byte containing hub/port address. Passes remainder.

– Reflects data back to Front End Controller.

Dual TBMHUB

TBM TBM

mI2C

4 mI2C Ports Output Only

Control Link

ROC ROCROC ROC

slide 8

Analog sectionsStacksControl sections Hub

5.3 mm

4 mm

DMILL Dual TBM

1st (& only)Sub. 5/02

It Works!

slide 9

• Power consumption 600 mW–core 140 mW –Differential Drivers 460 mW

• 6 Tested / 5 Fully Functional

TBM Test ResultsEvent # = 11 Status Reg.

Header ID Trailer ID

UBLK

0

1

2

3

Token Pass

• Header marker 3 “UBLK” + “1”–8 Bit Event Number (4 Clocks)

• Trailer marker 2 “UBLK” + 2 “1”–8 Bit Status Word (4 Clocks)

slide 10

Analog Adjustability

Before Adjustment

After Adjustment

TBM 1 TBM 2

slide 11

Header ID

Event Number Status Info

Trailer ID

Expected Max CMS Trigger Rate = 100KHz

1 MHz Trigger Rate

slide 12

Hub Testing

Serial Data

Serial Clock

mI2C Command Output From Port 0

• Internal fast port - fully tested and functional• External fast ports - fully tested and functional

slide 13

Changes For 0.25 m

• Reduce Power Consumption– Redesign LVDS Drivers– Minimize Clock Usage – Shut Down Clock when not needed

• Limit use of Analog bus– Pass ROC Analog Through TBM– Analog Output Line Driver

• Redesign Serial Protocol For CMS Optical Transceivers.– 8 Bit data + Complement Bit 8 4 Bit data + Complement Bit 4

– Request Modification to Optical Receiver Chip

• Allow Transition Dual Single TBM Operation

slide 14

TBM Operation Modes

ROC readout

ROC readout

Readout token chip 1-8

Half-Module Readout 1

Readout token chip 9-16 Half-Module Readout 2Dual Mode

ROCs

ROC readout

ROC readout

Readout token

Module ReadoutSingle Mode TBM

slide 15

10-17

10-16

10-15

10-14

10-13

10-12

1.4 1.81.6 2.0 2.2 2.4 2.6

SEU cross section of 0.25m Flipflop300 MeV/c pion beam

Standard: =2 x 10-13 cm2

Protected: =2 x 10-15 cm2 (284 ff per DTBM)

Single Event Upset

TBM Placement

Expected Flux

(MHz/cm2)

Time Per SEU

Protected F/F(Hrs/SEU)

4cm Barrel 40 12

7cm Barrel 20 24

11cm Barrel/

Foreward

8 60

[cm2]

Standard Latch Protected Latch

slide 16

“Fast” Hub

0.25 m Hub• IBM Process

– 3 metal layers– MIMCaps

• “Fast” Hub– Normally Part of TBM– Tested in Simulation with ROC

Control Section– PSI Low Power LVDS Drivers

• “Slow” Hub – Can reside on same control link

as Fast hubs– Provides Control data for PLL &

Laser Drivers Via I2c Protocol

• Submitted June 2003• Received: Sept. 19, 2003

“Slow” Hub

slide 17

Slow HubModified Version of Fast Hub

SerialData In

40 MHz Clock

Slow ClockOut

Start-Stop

8 BitReg.

AddressCompare

1 to 7Decoder

1 to 7Decoder

7 to 1Mux

DivideBy 256

OddDataBits

Slow DataI/O

SerialData

Return

Modifications

slide 18

0.25 m Dual TBM

3.2 mm

4.4 mm

Analog Readout

Analog Power

Regulators

Hub

Stacks

ControlSections

• IBM Process– 3 metal layers

– MIMCaps

• 3 voltage regulators – Core Digital– Analog– LVDS Drivers

• Pad Dominated

• Completed: October 2003– CERN rules check now– Nov 10th MPW submission

slide 19

2nd 0.25 m Version

Analog Readout

Analog Power

Regulators

Hub

Stacks

ControlSections

• Fix any bugs?

• Improvements– Rad-Hard regulator band gap reference

– More flexibility in token passing (bypass non-responding ROC segment)

– TBM Aout driver enhancements

• Spring 2004 submission?

slide 20

Conclusion

• Dual TBM worked on first DMILL submission• 0.25 m Fast and Slow Hubs are Awaiting Testing• 0.25 m TBM Complete

– 10 November 2003 MPW Submission

• Second 0.25 m Prototype Submission Anticipated

• Production TBM Available End of 2004