PADI, a fast Preamplifier - Discriminator for Time-of-Flight Measurements.
1
The primary charge of an RPC signal is between 25 - 100 fC equivalent to a 1- 4 mV amplitude (in 50 ) PADI, a fast Preamplifier - Discriminator for Time-of-Flight Measurements. M.Ciobanu 1,2 , N.Herrmann 1 , K.D.Hildenbrand 2 , M.Kiš 2,3 , A.Schüttauf 2 1 University of Heidelberg 2 GSI-Darmstadt 3 Rudjer Boskovic Institut Zagreb [email protected] Dominant components for deteriorating a time measurements Detector primary signals 1. The slewing or “Walk” correction: This component is due to the amplitude variation for a nearly constant rise time of the primary signal. PADI offers an analog differential signal as well as Time-over-Threshold (ToT) for this correction 2. More important for the electronic design is the so called "Jitter" which is dominated by the noise of the amplifier. The noise dispersion ( n at the falling/rising edge projected onto the time-axis allows to estimate the electronics resolution. In general, there exist an additive term (δ t ) which is due to the discriminator and time digitizer. t BW As Nd FEE t BW r t r t As THR V dt BW Nd n t dt dV n FEE t * 44 . 0 ) ( 35 . 0 8 . 0 @ dV bandwidth amplifier BW nois of density spectral Nd if ) ( -10 -5 0 5 10 -400 -300 -200 -100 0 100 200 300 PAD I#2,Linearity,5.5ns pulse applied atpositive and negative inputs Eout_diff[mVpk] U inp [m Vpk] C h1 C h2 C h3 LinearFit(-3m V -3m V) for A B C h1 -2.79 57.7 C h2 -2.05 56.4 C h3 -2.29 54.7 Vthr_chip=100m V 1 10 100 1000 1 2 3 4 5 6 7 8 9 10 P AD I#1,S hortPulse,Tim e overThreshold ToT [ns] U inp [m V] C h1 C h2 C h3 1 10 100 1000 1 10 100 t [ps] U inp [m V] 83m V 113m V 141m V 196m V 251m V 0 2 4 6 8 10 12 14 0 1 2 3 4 5 6 x10 5 E 356.68 M eV/u F#7 B eam intensity code #(1-15) pixel#1 pixel#2 pixel#4 Yield [hits /spill] Ionization C ham berYield [hits /spill] x10 7 1E7 1E8 1E9 5 10 15 20 25 30 35 40 PAD I#2 C h1P;Transm ission M easurem ent Pream p G ain [dB] Frequency [H z] C h1P 1E7 1E 8 1E 9 5 10 15 20 25 30 35 40 P AD I;Sim ulation on schem atics including Parasitics Pream p G ain [dB] Frequency [H z] C h1P 1E7 1E8 1E9 -60 -55 -50 -45 -40 -35 -30 -25 -20 -15 -10 -5 P A D I#2,C h3P Transm ission U /U 0 [dB] Frequency [H z] -40dB -50dB -60dB -70dB -80dB The experience acquired in the designing of the Front-End Electronics for the FOPI-ToF upgrade [1,2] was employed in development of the PADI-ASIC for the CBM-ToF detector. Inspired by the NINO-ASIC architecture [3], it is made in 0.18 m CMOS technology with following key design parameters: fully differential - 50 input impedance - PA gain of Gp> 100 - bandwidth of BWp> 300 MHz peaking time t pk < 1ns - noise related to input of V N-IN < 25 V RMS - power consumption P < 30 mW/ch - intrinsic electronic resolution of tE <15 ps PADI delivers an analog differential signal as well as Time-over-Threshold (ToT) for the slewing correction and an OR signal for trigger purposes. References: [1] A.Schuttauf et al, "Performance of the Multistrip-MRPCs for FOPI",Nuclear Physics B (Proc. Suppl.), Volume 158, August, 2006, Pages 52-55. [2] M.Ciobanu et al, "A Front-End Electronics Card Comprising a High Gain/High Bandwidth Amplifier and a Fast Discriminator for Time-of-Flight Measurements", IEEE Trans. on NS, Volume 54, Issue 4, Part 3, Aug. 2007 Pages:1201 - 1206 [3] F.Anghinolfi et al, "NINO: an ultra-fast and low-power front-end amplifier/discriminator ASIC designed for the multigap resistive plate chamber" NIM A, Volume 533, Issues 1-2, 1 November 2004, Pages 183-187 Motivati on The experimental performance of PADI-1 was tested with a 4 pixel single-crystal CVD Diamond detector exposed to a Carbon beam of 356*A MeV of 1.5x10 8 particles in a spill of 2 s length. By comparing the time dependence within spill and the integral rate for the 3 channels of PADI-1, we found an excellent uniformity within +/- 0.2 % for all channels. In an independent measurement with an ionization chamber as reference, we monitored the Carbon beam position and intensity. The yield of both detectors exhibits a linear relation for all 3 diamond pixels (see Fig.2), which indicates an excellent stability and linearity of the PADI chip up to rates of 75 MHz PADI-1: Three channel prototype with voltage biasing and differential outputs Submitted in July 2006 in CMOS UMC18 tech. Size: 1.5mm x 1.5mm PADI-2 and 3: Four channel prototypes with current biasing, quasi LVDS / true LVDS outputs for timing , OR input, output Submitted in Oct. 2008 in CMOS UMC18 technology. Size: 1.5mm x 3mm PADI-4: Four channels prototype with current biasing, Z IN ~680 Submitted in Oct. 2008 in CMOS UMC18 technology. Size: 1.5mm x 3mm PADI-1 Main technical parameters: Time resolution (@10mV) [ps] < 10 PA Gain (single input) ~ 60 PA Bandwidth [MHz] ~ 180 Linear range [mV] ~ -5 to 5 Noise (at input) [µV RMS ] ~32 CTRR [dB] ~ 26 - 40 CMRR [dB] > 40 Input impedance [] ~ 48 - 58 Power consumption [mW/Ch] ~ 31 PADI test PCB LVDS-PECL Converter PCB Interface PCB +5V,GND,THR connections Time Outputs LAN-K5 cable ~2.1m Cables to SC Diamond Pixel Detector Simulated Gain-to-Frequency dependence of the PADI-1 preamplifier; the parasitic effects from the ASIC layout are included. The -3dB points are fL=14MHz and fH =240MHz. Measured Gain-to-Frequency dependence of the PADI-1 preamplifier; the transmission measurements were performed with Spectrum Analyzer FSH3 (Rohde & Schwarz). The -3dB points are fL=14MHz and fH=180MHz. Gain-to-Frequency dependence, tested in a dynamics of 40dB of the AC input signal. The presence of local "bumps" can be correlated to a possible instabilitiy. The Time-over-Threshold (ToT) variation of the discriminated signal at the timing output reflects the input amplitude of the signal over a big dynamic range. Linearity of the preamplifiers: All three channels have a similar sensitivity; the differential analogue output is linear for an input signal interval of -5 to +5 mVpk. Time resolution versus the input signal amplitude (for different threshold voltages). Using PADI-1 to read out a polycrystalline CVD diamond in a heavy-ion beam we reached td <45 ps with a plastic scintillator detector as a reference ( t <62ps combined). PADI-1 test plate is connected to 3 pixels of the Single Crystal CVD diamond detector and to a standard NIM-CAMAC data acquisition system which was programmed to measure rates [hits/ms]. The left figure show the rate histograms over the 2 s spill (with 110 spills integrated). The total number of hits in the 3 channels agrees within +/-0.2%. In the right figure, the yield of the diamond/PADI detection system is compared to that of an ionization chamber; a very linear correlation is observed up to ~1.35x10 8 hits/spill (the 3 pixels see different beam intensities which is reflected in the different slopes). Complete detector-electronics board including two PADI-1chips to read out a polycrystalline CVD diamond. It is to be used as a very compact START and HALO detector for beam monitoring.
description
Time Outputs LAN-K5 cable ~2.1m. Cables to SC Diamond Pixel Detector. Interface PCB +5V,GND,THR connections. LVDS-PECL Converter PCB. PADI test PCB. PADI, a fast Preamplifier - Discriminator for Time-of-Flight Measurements. - PowerPoint PPT Presentation
Transcript of PADI, a fast Preamplifier - Discriminator for Time-of-Flight Measurements.
The primary charge of an RPC signal is between 25 - 100 fC equivalent to a 1- 4 mV amplitude (in 50 )
PADI, a fast Preamplifier - Discriminator for Time-of-Flight Measurements.
M.Ciobanu1,2, N.Herrmann1, K.D.Hildenbrand2, M.Kiš2,3 , A.Schüttauf2 1 University of Heidelberg
2 GSI-Darmstadt 3 Rudjer Boskovic Institut Zagreb
Dominant components for deteriorating a time measurements
Detector primary signals1. The slewing or “Walk” correction: This component is due to the amplitude variation for a nearly constant rise time of the primary signal. PADI offers an analog differential signal as well as Time-over-Threshold (ToT) for this correction 2. More important for the electronic design is the so called "Jitter" which is dominated by the noise of the amplifier. The noise dispersion (n) at the falling/rising edge projected onto the time-axis allows to estimate the electronics resolution. In general, there exist an additive term (δt) which is due to the discriminator and time digitizer.
tBWAs
NdFEEt
BWrt
rt
AsTHRV
dt
BWNdn
t
dtdVn
FEEt
*44.0)(
35.0
8.0@dV
bandwidthamplifier BW
noise ofdensity spectral Nd
if
)(
-10 -5 0 5 10-400
-300
-200
-100
0
100
200
300
PADI #2, Linearity, 5.5ns pulse applied at positive and negative inputs
Eou
t_di
ff [m
Vpk
]
Uinp [mVpk]
Ch1 Ch2 Ch3
Linear Fit (-3mV - 3mV)for A BCh1 -2.79 57.7Ch2 -2.05 56.4Ch3 -2.29 54.7
Vthr_chip=100mV
1 10 100 10001
2
3
4
5
6
7
8
9
10
PADI #1, Short Pulse, Time over Threshold
ToT
[ns]
Uinp [mV]
Ch1 Ch2 Ch3
1 10 100 10001
10
100
t [ps]
Uinp [mV]
83mV 113mV 141mV 196mV 251mV
0 2 4 6 8 10 12 140
1
2
3
4
5
6
x105 E 356.68 MeV/u F#7 Beam intensity code #(1-15)
pixel#1 pixel#2 pixel#4
Yie
ld [h
its /
spill
]
Ionization Chamber Yield [hits / spill]x107
1E7 1E8 1E95
10
15
20
25
30
35
40
PADI #2 Ch1P; Transmission Measurement
Pre
amp
Gai
n [d
B]
Frequency [Hz]
Ch1P
1E7 1E8 1E95
10
15
20
25
30
35
40
PADI; Simulation on schematics including Parasitics
Pre
am
p G
ain
[d
B]
Frequency [Hz]
Ch1P
1E7 1E8 1E9
-60
-55
-50
-45
-40
-35
-30
-25
-20
-15
-10
-5
PADI #2, Ch3P Transmission
U/U
0 [d
B]
Frequency [Hz]
-40dB -50dB -60dB -70dB -80dB
The experience acquired in the designing of the Front-End Electronics for theFOPI-ToF upgrade [1,2] was employed in development of the PADI-ASICfor the CBM-ToF detector. Inspired by the NINO-ASIC architecture [3], it ismade in 0.18 m CMOS technology with following key design parameters:fully differential - 50 input impedance - PA gain of Gp> 100 - bandwidth of BWp> 300 MHzpeaking time tpk< 1ns - noise related to input of VN-IN < 25 VRMS - power consumption P < 30 mW/ch - intrinsic electronic resolution of tE <15 ps PADI delivers an analog differential signal as well as Time-over-Threshold (ToT) for the slewing correction and an OR signal for trigger purposes.
References:[1] A.Schuttauf et al, "Performance of the Multistrip-MRPCs for FOPI",Nuclear Physics B (Proc. Suppl.), Volume 158, August, 2006, Pages 52-55. [2] M.Ciobanu et al, "A Front-End Electronics Card Comprising a High Gain/High Bandwidth Amplifier and a Fast Discriminator for Time-of-Flight Measurements", IEEE Trans. on NS, Volume 54, Issue 4, Part 3, Aug. 2007 Pages:1201 - 1206 [3] F.Anghinolfi et al, "NINO: an ultra-fast and low-power front-end amplifier/discriminator ASIC designed for the multigap resistive plate chamber" NIM A, Volume 533, Issues 1-2, 1 November 2004, Pages 183-187
Mo
tiva
tio
n
The experimental performance of PADI-1 was tested with a 4 pixel single-crystal CVD Diamond detector exposed to a Carbon beam of 356*A MeV of 1.5x108 particles in a spill of 2 s length. By comparing the time dependence within spill and the integral rate for the 3 channels of PADI-1, we found an excellent uniformity within +/- 0.2 % for all channels. In an independent measurement with an ionization chamber as reference, we monitored the Carbon beam position and intensity. The yield of both detectors exhibits a linear relation for all 3 diamond pixels (see Fig.2), which indicates an excellent stability and linearity of the PADI chip up to rates of 75 MHz
PADI-1: Three channel prototype withvoltage biasing and differential outputsSubmitted in July 2006 in CMOS UMC18 tech. Size: 1.5mm x 1.5mm
PADI-2 and 3: Four channel prototypeswith current biasing, quasi LVDS / trueLVDS outputs for timing , OR input, outputSubmitted in Oct. 2008 in CMOS UMC18 technology. Size: 1.5mm x 3mm
PADI-4: Four channels prototypewith current biasing, ZIN ~680 Submitted in Oct. 2008 in CMOS UMC18 technology.Size: 1.5mm x 3mm
PADI-1 Main technical parameters:
Time resolution (@10mV) [ps] < 10PA Gain (single input) ~ 60PA Bandwidth [MHz] ~ 180Linear range [mV] ~ -5 to 5Noise (at input) [µVRMS] ~32CTRR [dB] ~ 26 - 40CMRR [dB] > 40Input impedance [] ~ 48 - 58Power consumption [mW/Ch] ~ 31
PADI test PCB
LVDS-PECL
Converter PCB
Interface PCB
+5V,GND,THR
connections
Time Outputs
LAN-K5 cable
~2.1m
Cables to
SC Diamond
Pixel Detector
Simulated Gain-to-Frequency dependence of the PADI-1 preamplifier; the parasitic effects from the ASIC layout are included. The -3dB points are fL=14MHz and fH =240MHz.
Measured Gain-to-Frequency dependence of the PADI-1 preamplifier; the transmission measurements were performed with Spectrum Analyzer FSH3 (Rohde & Schwarz). The -3dB points are fL=14MHz and fH=180MHz.
Gain-to-Frequency dependence, tested in a dynamics of 40dB of the AC input signal. The presence of local "bumps" can be correlated to a possible instabilitiy.
The Time-over-Threshold (ToT) variation of the discriminated signal at the timing output reflects the input amplitude of the signal over a big dynamic range.
Linearity of the preamplifiers: All three channels have a similar sensitivity; the differential analogue output is linear for an input signal interval of -5 to +5 mVpk.
Time resolution versus the input signal amplitude (for different threshold voltages).
Using PADI-1 to read out a polycrystalline CVD diamond in a heavy-ion beam we reached td<45 ps with a plastic scintillator detector as a reference (t<62ps combined).
PADI-1 test plate is connected to 3 pixels of the Single Crystal CVD diamond detector and to a standard NIM-CAMAC data acquisition system which was programmed to measure rates [hits/ms]. The left figure show the rate histograms over the 2 s spill (with 110 spills integrated). The total number of hits in the 3 channels agrees within +/-0.2%. In the right figure, the yield of the diamond/PADI detection system is compared to that of an ionization chamber; a very linear correlation is observed up to ~1.35x108 hits/spill (the 3 pixels see different beam intensities which is reflected in the different slopes).
Complete detector-electronics board including two PADI-1chips to read out a polycrystalline CVD diamond. It is to be used as a very compact START and HALO detector for beam monitoring.
