6mm

【 【 Development of Readout Electronics for Development of Readout Electronics for MPPC MPPC 】】

We report the read out electronics of MPPC( Multi-Pixel Photon Counter ). MPPC is a new photodetector developed by Hamamatsu Photonics. Here, we report Trip-t ASIC chips and those electronics. We report the read out electronics, Trip-t Test Board. MPPC and Trip-t chip have been decided to use in T2K experiment. We now test the basic performances of latest MPPC samples, and check the device-by-device variation about many samples with Trip-t Test Board. Trip-t Test Board can be used for reading out signals from 32 MPPC at the same time.

Trip-t chipTrip-t chip

・ Developed by FNAL・ Used in D0 experiment・ Plan to use in T2K experiment and MINERvA experiment・ Input 32ch Analog signal ( - )・ Output

KEK Trip-t Board 　 Blockdiagram

Trip-t & MPPC Mount Board

MPPC Mount Board with 32 MPPCMPPC Mount Board with 32 MPPC

LabviewLabview

…with Plastic Connector for connecting MPPC to wave length shifting fiber

Trip-t Block Diagram

… … Distal wave generatorDistal wave generator

1. Discri signal of each 32ch2. Analog signal proportional to input signal3. Analog signal proportional to the time between

input signal and gate signal

:

:

Trip-t Test Board for Measurement

Example Histogram by Trip-tExample Histogram by Trip-tExample Histogram by Trip-tExample Histogram by Trip-t

For T2K experiment, ~60000 samples of MPPC must be measured. By this test board, we can measure 32 MPPCs at the same time.

Now, we construct the system for mass production of MPPC samples for T2K experiment with this 32ch test board.

Takeshi.Murakami*,Shinichi.Gomi KEK*,Department of Physics, Kyoto University

Trip-tTrip-t

PS1

PS2

MPPC Mount socket

40Pin connector

68

Pin

co

nn

ec

tor

40Pin 2line Header pin

AD827 op

filter

Regulator

DC70V

±5V to 2.5V

D-OUT

to Logic Analyzer

PP

G M

od

ule

(VM

E)

Lab

view

sys

tem

34

Pin

co

nn

ec

tor

DAQ Board(VME);to ADC

Vth OUTP_A

AC

Con. Sig.

32 MPPC

Test pin

32

Cable change

0 to

2.5V

32

(10mm space x2)

85QLAx285QLAx2

Injection

MPPC Mount Board

34

Pin

co

nn

ec

tor

34

Pin

co

nn

ec

tor

34

Pin

co

nn

ec

tor

34

Pin

co

nn

ec

tor

34

Pin

co

nn

ec

tor

190mm

65mm

190mm

155mm

±5VIN

MPPC Hole 5.3φ（ 32 Mount）

Bias controlBias control

MPPC Mount SideMPPC Mount Side Trip-t Mount SideTrip-t Mount Side

40pin connector×2

ADC;AD9220

VME SIDE

J0 FPGA;XC3S400PQ208

DAC;MAX529C

LK

BU

SY

TR

G-A

TA

-AT

RG

-BT

A-B

VME IF ;FPGA;XC95144XL-TQ144

VME6U DAQ BoardVME6U DAQ Board

MPPC SIGNAL(CH1)

Pre-AMP RESET

Pre-AMP after MPPC signal

CLOCK(mux)0 1 2 32

T_OUTMPPC Signal

D_OUT

Pipeline Clock time Voltage

A_OUT

Trip-t readout sequence

Trip-t Position

MPPC ( Multi-Pixel Photon Counter )MPPC ( Multi-Pixel Photon Counter )

• Multi-Pixel Photon Counter ( = MPPC ) is a new type of photo detector developed by Hamamatsu Photonics (HPK).

• MPPC consists of 100~1600 small avalanche photo diodes( APD ) in 1mm×1mm sensitive region.

1pixel mm 5050

Sensitive region of MPPC

• MPPC advantages– CompactCompact– Insensitive to magnetic fieldInsensitive to magnetic field– High gain( ~10High gain( ~1066 ), low bias voltage( ~70V ) ), low bias voltage( ~70V )– High photon detection efficiencyHigh photon detection efficiency– Excellent photon counting capabilityExcellent photon counting capability

The left figure is MPPC raw signal. MPPC has good photon counting capability.

By using Trip-t Test Board, we are now measuring about the basic performances and device-by-device variation of MPPC for T2K experiment.

ch2

A_Pipeline48x32ch

T_Pipeline48x32ch

Analog MUX

AnalogMUX

AnalogMUX

Signal to Stocks （ Deep;1-

48 ）32chIN → Serial out

FrontEnd

T_OUT(Time)

A_OUT (Charge)

D_OUT(discri signal)

• AMP• Discri signal

ch1

ch2

ch32

ch1ch32

Trip-tTrip-t ･･･ TRITRIgger and PPipeline with TTiming

Trip-t Performances

LinearityLinearityLinearityLinearity

High Gain

Low Gain

Input charge versus. ADC count

When the gain of Trip-t is high, linearity become wrong at low charge region.

Cross-talkCross-talkCross-talkCross-talk

Check the signal cross-talk to the another input channel.

Cross-talk is small enough.

Input only No.15 channel

)count(15ch ADC

channel) count(each ADC

0.4%0.4%

The injected charge to each channel is amplified by the front-end amplifiers and stored in pipeline before readout. Next the stored signals are serialized to 1 channel by multiplexer which is located at the last stage of Trip-t. Using 1 Trip-t, we can reduce the number of readout channels from 32 to 1.

Simply speaking, A_OUT corresponds to the amplitude of input charge, T_OUT corresponds to the timing of input charge and D_OUT corresponds to the digital information of input charge.

SerializedSerialized

Total 128pins

Those 2 boards, Labview and VME are connected by flat cable.

Trip-t power supplies

VDDD(digital)=+2.5V , VDDA(analog)=+2.5V

OPAMP power supplies ･･･ ±5V

Power supply

Trip-t OPAMP

RegulatorRegulator+5V +5V +2.5V +2.5V

+5V -5V

The DAQ(Data AcQuisition) board is a VME standard module and was originally developed for the SciBar detector in K2K experiment. We use this DAQ board for an analog-to-digital conversion of A_OUT from Trip-t.

Several modifications are made to the DAQ board in order to adjust it to the readout of MPPCs.

1. Since A_OUT of Trip-t has 1.0V DC offset, we put A_OUT to the outm of the DAQ board and DC+1V to the outp. By subtracting the outp from the outm, A_OUT has no offset.

2. We change the gain of DAQ board from 20 to 1 because the gain of the Trip-t is enough high.

MPPC raw signal

Input to 10CHInput to 10CH

VME

1 ･ 2 ･ 3 ･ 4 ･ 5 ･ 6 ･ 7 ･ 8 ･ 9 ･ 10 ･ 11 ･･･ 10 11 12 13

1PE

2PE

3PE

Pedestal

1PE2PE3PE

Pedestal

1PE

2PE

3PE

PedestalBasic performances of MPPCBasic performances of MPPC

When we use all 32 channel, each output come at each MUX positions as those figure.

PD07 International for poster Jun 27-29,2007 Kobe