MSCF-16
PMT(Data sheet V5.1_02)

16 fold Spectroscopy
Amplifier with CFDs
and Multiplicity Trigger

mesytec MSCF-16-PMT is an integrating shaping / timing filter amplifier with constantfraction discriminator and multiplicity trigger. It provides 50 Ω terminated Lemo 00 inputs,
and directly processes fast negative signals from PMTs or other charge sources.
Features:• 16 channel NIM module, low power design• directly interfaces to anode signals from photo multipliers• Shaping amplifiers with active baseline restorer• Timing filter amplifiers• CF discriminators (opt.: leading edge)• ECL timing output with digital delay of 400 ns• Trigger output• Multiplicity trigger• Remote control of discriminator thresholds,
shaping time, gains and PZ• 4 shaping times• Gain adjustable from 100 pC to 20 nC for max range• 50 Ω terminated Lemo 00 input.
• Low noise (0.2 pC rms / 2 pC rms)
• Mostly controllable via front panel• Remote control via USB and mesytec control bus• 4 selectable timing filter integration times• ECL timing delay can be switched offSchematics:

mesytec GmbH & Co. KG
Wernher-von-Braun-Str. 1, D-85640 Putzbrunn, Germany
phone: +49 - 89 / 456007-30 fax: +49 - 89 / 456007-39
info@mesytec.com - www.mesytec.com

MSCF-16 PMT

16 fold shaper with CFD

Fraction and delay selection of
the 4 channel CFD plug on modules

Technical Data
Input stage• Gain adjust: gain can be set from 1 to 20 in 16
steps with factor 1.22 per step.
• Input connectors: 16x Lemo 00 series.
• Input termination 50 Ω, coded on thegain-polarity jumper.
• Gain jumpers with sensitivity
100 pC…2 nC and 1 nC…20 nC are standard.
(Optional 50 pC…1 nC)• Max allowed input offset: for 1 nC jumper:±5 mV, for 20 nC jumper: ±100 mV.
(direct PMT signals have no offset)
Shaper• PZ is preadjusted and usually needs not to beuser adjusted.
• 5th order Shaper(4th order for 0.12 us to 1 us type)• Four shaping times• selectable for groups of 4 channels• Output amplitude: 0 to 10 V
• Active baseline restorer with settable threshold.
(via RC only).
• DC-Offset with BLR: VDC ±5 mV,• common offset adjust.
• Output connector: 34 pin male connector• Integral non linearity <0.1 %• gain drift <0.01 % /°C• Offset drift with BLR <50 V /°C
Noise• For 1 nC jumper the noise is 0.1 pC rms• For 2 nC jumper the noise is 0.2 pC rms• For 20 nC it is 2 pC rms
Timing filter amplifier• Time constants see table at the end ofdata sheet
Discriminator• CFD or Leading edge (jumper selectable)• CFD delays, and fraction selectable for groupsof 4 channels• CFD-Walk: for 30 ns (10 % to 90 %) input risetime, max ±1 ns (dynamic range 100:1)• Threshold: adjustable, 0 % to 30 %• of maximum range, in 256 steps.

Example: CFD-60

Fraction (sw1)
On: 20 %Off: 40 %Delay (sw1, sw2)
off off: 10 ns
on off: 20 ns
off on: 40 ns
on on: 60 ns

For other CFD delays see section „Types and ordering”
See also label inside the movable module side plate.

Gate generator,Timing delay,ECL output• Pulse width for trigger output: 400 ns• Timing stop- ECL-Signals:delay 400 or 800 ns from trigger, width 200 ns• Output connector: 34 pin male connector
Monitor output• output for timing filter signals• output for amplitude signals• selectable by rotary switch(Signal quality of monitor outputs may beslightly degraded compared to direct outputs.)
Multiplicity trigger• Each channel above threshold contributes tomultiplicity level, a multiplicity trigger isgenerated for: lower multiplicity threshold≤ multiplicity level ≤ upper multiplicitythreshold• Coincidence interval adjustable from 20 ns up
to 200 ns (default 75 ns).
• The multiplicity trigger is delayed by thecoincidence time to the trigger signal.
• Multiplicities selectable via remote control• Lower multiplicity threshold: 1 … 8, upper
multiplicity threshold: 1 … 8 and ∞• Multiplicity chaining: multiplicity outputs fromseveral modules can be connected,resulting in a total multiplicity level of all connected modules. Multiplicity trigger
windows of the connected modules act
independently on the total multiplicity.
Power consumption: (max 9 W)

• +6 V• –6 V• +12 Vmesytec GmbH & Co. KG
Wernher-von-Braun-Str. 1, D-85640 Putzbrunn, Germany
phone: +49 - 89 / 456007-30 fax: +49 - 89 / 456007-39
info@mesytec.com - www.mesytec.com

300 mA–700 mA
200 mA

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MSCF-16 PMT

16 fold shaper with CFD

MSCF-16 Front panel Operation

Gain

Most MSCF-16 parameters can be set andcontrolled via front panel elements.

Gain values are set by the gain dial, gain values areindicated on the front panel. Gain ranges from
1.0 to 20.0. It can be set commonly for all
channels or individual for groups of four channels.

Two parameters can be adjusted for each channel
individually:• Threshold• PZ compensation
Two parameters can be adjusted in groups of fourchannels (channel 1–4, 5–8, 9–12 and 13–16):• Gain• Shaping time
All parameters can as well be set up for all
channels in common. Thus there are two different
modes of front panel operation:
Common mode:
Threshold, PZ, Gain and Shaping time
have a common setting for all channels

ThresholdThreshold is adjusted with a front panel trimmer,
the corresponding voltage can be drawn from thetest output. It can be set commonly for allchannels or individually for each channel.
PZ

PZ compensation is also adjusted with a front
panel trimmer, the corresponding voltage level isoutput on the test connector. It can be set
commonly for all channels or individually for eachchannel.
General setup
Common mode

Single mode:
Threshold and PZ settings for eachindividual channel
Gain and Shaping time for each groups offour channels

In common mode, the trimmer settings forthreshold and PZ are followed immediately.
Shaping time can be selected for all channels clicking the Sht knob. Gain is set for all channels by selecting the desired gain switch position.

Common parameters can be copied to individual
parameters to easily get a basis for individual
settings.

Individual mode

Mode selectClicking the “single chan” knob switches between
single and common operating mode. The orange
LED associated with the “single chan” knob
signals single channel mode when lighted.

In single channel mode, trimmer changes are only
read and activated when the “enter” knob ispressed during changes. Threshold and PZ
settings are remembered individually for eachchannel. Shaping times and gains are valid for agroup of four channels.
Copying from Common to Individual

One out of 16 available channels is available at theenergy and timing monitor outputs. This is also thechannel to be modified in Single mode.

For an easy basic setup, common settings can becopied to the individual section. Fine tuning canthen be done based on this basic setup.
Copy is done by clicking the “Single chan” knob
while “enter” is pressed.

Shaping time

Auto PZ setup

Shaping times are changed around by clicking the“Sht” knob, the shaping time value of thecurrently selected channel (group) is displayed by
two LEDs. They indicate an index from 0(“1” and “2” LEDs both off) up to 3
(both LEDs on). Please refer to individual device
labeling for corresponding shaping times.

The PZ compensation values can be set up
automatically – provided there’s a signal at therespective channels.

Monitor / Active Channel

mesytec GmbH & Co. KG
Wernher-von-Braun-Str. 1, D-85640 Putzbrunn, Germany
phone: +49 - 89 / 456007-30 fax: +49 - 89 / 456007-39
info@mesytec.com - www.mesytec.com

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MSCF-16 PMT

16 fold shaper with CFD

Holding the “Single chan” knob for about two
seconds starts the automatic pz setup. The values
found are saved in the individual parameter set.
Clicking “Single chan” again during autopz stops
the process.

For common settings, there’s one virtualchannel/group added to parameter indices:

Remote Controlled Operation

Gain, shaping time:Groups 1 … 4, 5 = common.

MSCF-16 can be remotely controlled in two ways:
USB control and event bus control.
MSCF-16 has two complete parameter sets, one forfront panel operation, one for remote control.
Switching RC on and off switches between thesetwo parameter sets.
In RC mode there are several more parameters,
which will also be used (but can not be controlled)
in front panel mode:
•••
•
•
•

BLR on/off
Coincidence time window
Shaper offset
Threshold offset
BLR threshold
Multiplicity trigger thresholds

Thresholds, pz compensation:
Channels 1 … 16, 17 = common

Command list: (each cmd terminated by <CR>)DSSB nSG group val
SBL valSC val
SSO val
STO val
SBT valST chan val

USB Control

For USB control a USB 1.1 or 2.0 connection is required. The MSCF-16 can be operated as ageneric serial device on a virtual com port. Virtual
Com Port (VCP) drivers for various operating
systems for this rc mode can be derived from themanufacturer of the USB interface chip:www.ftdichip.com/Drivers/VCP.htm

SP chan val
SS group val
SM hi lo

The MSCF-16 can then be controlled e.g.
using a terminal program or a proprietarycontrol software.

MC chanInterface settings

ONOFFAPAP chan
CPY F

By default, communication is set to:
9.6 kBd, Data format 8N1
Higher baud rates can be set using the “SB” cmd.
On power-up 9.6 kBd will be restored.

SI 0/1CPY R
Device Parameters

Like in front panel mode thresholds and pz values
can be adjusted in common or individually for eachchannel, while shaping times and gains can be setup for groups of four channels or incommon.

VDisplay Setup (lists all gains, thresholds, pz values, shaping times, …)
Set Baud rate to:n = 1: 9.600 Bd. (Power-Up default)
2: 19.200 Bd.
3: 28.400 Bd.
4: 57.600 Bd.
5: 115.200 Bd.
Set Gain for groups of 4 channels
group = 1…5 (5 = common mode)val = 0…15
Switch BLR on/off (1/0)
Set coinc time window (0..255)
Set shaper offset (0..200) def. 100
Set threshold offset (0..200) def. 100
Set BLR threshold (0..255)
Set threshold valuechan = 1…17 (17 = common mode)val = 0…255
Set pz valuechan = 1…17 (17 = common mode)val = 0…255
Set shaping time for a group
group = 1…5 (5 = common mode)val = 0…15
Set multiplicity borders
hi, lo = 1 … 8
Set monitor output to chanchan = 1…16Single channel mode0 = off, 1 = on
Switch RC mode on
Switch RC mode off
Switch automatic pz setting on/off
automatic pz setting for chan 1..16
Copy fontanel settings to RC memory
Copy RC settings to front panel
memory
Display firmware version

Settings via USB remote control will be saved inpermanent memory and will be restored after next
power up.

mesytec GmbH & Co. KG
Wernher-von-Braun-Str. 1, D-85640 Putzbrunn, Germany
phone: +49 - 89 / 456007-30 fax: +49 - 89 / 456007-39
info@mesytec.com - www.mesytec.com4/7

MSCF-16 PMT

RC bus control
MSCF-16 can also be controlled using theMRC-1 / MRCC master controller modules.
Bus setup

Up to 32 devices (not only MSCF-16)– 16 on each of the two control buses –can be remotely controlled at a time.
Devices have to be connected with lemo cables andt-pieces, the last module on a bus has to be terminated with 50 Ω. The RC master is self
terminated. Be sure to assign individual device
addresses using the address coders!
RC commands

Remote control via RC bus is basically performedby reading and writing the control register page ofthe MSCF-16. Basic commands are:Read:
Write (Set):

RE b a m
SE b a m v

With:
b=

bus number (0/1)

a=device address (0...15)

m=

memory addressv=value16 fold shaper with CFD

18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48

Threshold channel 14
Threshold channel 15
Threshold channel 16
Threshold common
PZ value channel 1
PZ value channel 2
PZ value channel 3
PZ value channel 4
PZ value channel 5
PZ value channel 6
PZ value channel 7
PZ value channel 8
PZ value channel 9
PZ value channel 10
PZ value channel 11
PZ value channel 12
PZ value channel 13
PZ value channel 14
PZ value channel 15
PZ value channel 16
PZ value common
Shaping time group 1
Shaping time group 2
Shaping time group 3
Shaping time group 4
Shaping time common
Multiplicity hi
Multiplicity lo
Monitor channel
Single channel mode
RC49
50
51
52
53
54

Version information
BLR threshold
BLR on/off
Coinc. TimeThreshold offset
Shaper offset

Memory List MSCF-16
The following table shows the MSCF-16 memory
layout:
ADR01234567891011121314151617parameter
Gain group 1
Gain group 2Gain group 3
Gain group 4Gain common
Threshold channel 1
Threshold channel 2Threshold channel 3
Threshold channel 4Threshold channel 5Threshold channel 6
Threshold channel 7
Threshold channel 8
Threshold channel 9
Threshold channel 10
Threshold channel 11
Threshold channel 12
Threshold channel 13

comment
Gain setting forchannel 1 … 3 andcommon mode
Values from 0 … 15
Threshold values forchannel 1 … 16,17 = common
Values from 0 … 255

PZ values for channel
1 … 16,
17 = common
Values from 0 … 255

Shaping time settingsfor group 1 … 3 andcommon mode Values
from 0 … 3
Multiplicity values
1…81 … 16
1 = on, 0 = off
1 = on, 0 = off(set automatically by
ON/OFF cmd via
MRC-1 / MRCC)
16* maj + min.
0 … 255
1 = on, 0 = off
0 … 255
100 (=on offs) +/- 100
100 (=on offs) +/- 100

Parameters can be read / written while RC on oroff, but will take effect only when RC is on.
While RC ON, the front panel control will beblocked until “Enter” is pressed.
When shut down during RC on, the RC values will
be restored after next power up and rc will be active again.
Identification code for MSCF-16 (detected whenrunning the scan bus command "SC") is IDC = 21.

mesytec GmbH & Co. KG
Wernher-von-Braun-Str. 1, D-85640 Putzbrunn, Germany
phone: +49 - 89 / 456007-30 fax: +49 - 89 / 456007-39
info@mesytec.com - www.mesytec.com

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MSCF-16 PMT

16 fold shaper with CFD

MSCF-16 PCB overview

1:Position for the active gain-polarity jumpers.
2:
Position to store up to 4 spare jumpers
3:
BLR on/off, ECL Trigger delay on/off
4:
Timing filter integration time
5:50 Ω jumper. Is needed if modules are not connected for common multiplicity.
6 to 9: Connector usually occupied by CFD modules. To use only leading edge discriminators,remove CFD module and insert 16 jumpers at the upper side, 4 for each connector.
The lower pair on each connector is ground and can be left free.

mesytec GmbH & Co. KG
Wernher-von-Braun-Str. 1, D-85640 Putzbrunn, Germany
phone: +49 - 89 / 456007-30 fax: +49 - 89 / 456007-39
info@mesytec.com - www.mesytec.com

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MSCF-16 PMT

16 fold shaper with CFD

Types and ordering
Example MSCF-16_F for PMT readoutAppl.

Fast

Module name

Shaping Timing
times
filter(sigma) integration

MSCF-16_F _SH1 -5
0.1 us,0.2 us,0.5 us,1.0 us

5 ns

TF-dif:
33 ns,
70 ns,
150 ns360 ns

Input type_C

Input connector

Discriminator

CFD-Delay

_L

_CFD

60

Current for direct Lemo
PMT signals

Constant fraction (avail. 30,60, 120,discriminator_V_LE

Voltage, for current preamp signals_D
Differential
header 17x2200 ns)

Or leading edge
onlyConnected parameters: The timing filter differentiation time corresponds to the selected shaping time.
So shortest shaping time results in shortest TF differentiation time.
CFD plug in modules (4 modules per MSCF-16 needed)
CFD-Name
CFD-30
CFD-60
CFD-120
CFD-200

Fraction(via dip switch)
20 % / 40 %20 % / 40 %20 % / 40 %20 % / 40 %Delays(via dip switch)
5, 10, 20, 30 ns
10, 20, 40, 60 ns
20, 40, 80, 120 ns
30, 60, 130, 200 ns

Integrating standard types
Appl.
fast decay
time scintillators:
Plastic, LYSO…

Module name
MSCF-16_F_SH1-5_C_L_CFD30

commentShaping times: 0.12 us, 0.25 us, 0.5 us, 1 us (sigma)
Gain jumpers: 2 nC-50 R, 20 nC-50 R
ECL output delay 0 or 0.4 us
TF differentiation time of 33, 70, 150, 360 ns
TF integration time 5, 8, 15, 25 ns
BLR threshold step: 5 mV (max 1.25 V)

medium decay
time scintillators:
BGO, NaI

MSCF-16_F_SH2-20_C_L_CFD200

Shaping times: 0.25 us, 0.5 us, 1 us, 2 us (sigma)
Gain jumpers: 2 nC-50 R, 20 nC-50 R
ECL output delay 0 or 0.4 us
TF differentiation time of 70, 150, 300, 600 ns
TF integration time 30, 40, 80, 120 ns
BLR threshold step: 5 mV (max 1.25 V)

slow decay time
scintillators:
CsI

MSCF-16_F_SH8-70_C_L_LE

Shaping times: 1 us, 2 us, 4 us, 8 us (sigma)
Gain jumpers: 2 nC-50 R, 20 nC-50 R
ECL output delay 0 or 0.8 us
TF differentiation time of330 ns, 650 ns, 1.5 us, 3.3 us
TF integration time 40,80,150,220 ns
BLR threshold step: 5 mV (max 1.25 V)

mesytec GmbH & Co. KG
Wernher-von-Braun-Str. 1, D-85640 Putzbrunn, Germany
phone: +49 - 89 / 456007-30 fax: +49 - 89 / 456007-39
info@mesytec.com - www.mesytec.com

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