Click model number for photo
The Model 2262 is a high-speed, waveform digitizer providing high
resolution, multichannel solutions to waveform recording
requirements. Designed in a modular standard for ease of system
configuration, the 2262 offers four digitizers per module. The 2262
is compatible with CAMAC (IEEE-583), and works with IBM PC-based
software for easy, user oriented, waveform display and control.
The 2262 is DC-coupled with an analog bandwidth in excess of 40 MHz.
User selectable sampling rates up to 80 MS/sec coupled with 10-bit
resolution and dynamic range match a broad spectrum of applications.
The 2262 excels in applications such as chamber and detector
development for nuclear physics.
Fast Digitizing Rate - Standard sampling rate is 40
megasamples/sec. The 2262 Biphase Mode results in doubling (80
megasamples/sec) of the sample rate at the expense of two signal
inputs.
Multiple Independent Inputs - Each 2262 has four inputs and is
capable of measuring four waveforms simultane ously at the sampling
frequency or two waveforms at double that frequency.
Built-in Calibration Trim DACs - Internal DACs allow
calibration under software control to ensure maximum fidelity of
measurement regardless of the time and temperature.
High Resolution - A wide 10-bit dynamic range gives 1.5 mV
resolution over a full scale of 1.53 V, providing maxi mum detail
capture in the measurement.
Convenient Test Capability - Front-panel input applies
identical test signals to all four channels.
Bipolar Operation - Input range is a full 1.5 V, offset
anywhere between -1.5 V and +1.5 V to ensure adaptability to the
polarity characteristics of the signal.
Fast Clear Input - Should post-trigger factors demand, fast
clear allows simultaneous conversion abort in all chan nels. Readies
the 2262 for a new measurement.
Internal or External Time Base - Instead of the internal
crystal oscillator, an external time base can be used to introduce a
custom clock and to permit the synchronization of more than one
2262.
Very High Density - Up to 40 recording channels can be
accommodated in a standard LeCroy Model 8025 rack -mount power
housing. Up to 80 channels can be implemented with external +12 V
power.
GPIB (IEEE 488) and/or CAMAC (IEEE 583) Programmable - The
2262 plug-ins can be controlled and read out by LeCroy Model 8901A
interface and GPIB or via any direct standard CAMAC interface
available for a variety of computers.
The Model 2262 is a multichannel waveform digitizer based upon the
LeCroy MVV200 high performance charge coupled device (CCD). It may be
operated in one of two modes, Uniphase or Biphase. Uniphase mode
provides four channels at up to 40 MHz sampling rates. Each of the
four channels has a record length of 316 samples. In the Biphase
mode, two channels are internally tied to one input connector and
alternately sampled to provide an effective sampling rate up to 80
MHz and a record length of 632 samples.
The signal to be digitized may be connected directly to the 1.5 V
full-scale input or via a modular amplifier (LeCroy 6103) if gain
control is required. The operating range of 1.5 V may be offset via
front-panel control over a range of anywhere between -1.5 V and +1.5
V. Test points at the front panel monitor the offsets to facilitate
settings. Internal calibration DACs allow fine trimming of offset
characteristics via software control to ensure maintenance of full
dynamic range during use.
The 2262's sample clock can be internally or externally driven. The
clock source is controlled by a front-panel switch. The internal
clock is a plug-in hybrid crystal oscillator which provides a stable,
free-running time base. An 80 MHz oscillator is factory supplied with
the unit. The oscillator is followed by a 2:1 divider to generate the
40 MHz sampling clock with a precise 50% duty cycle. Use of an
external clock provides convenient variable-speed sampling. The CLK
OUT feature may be used to synchronize two or more 2262s to the same
time base.
The Model 2262 is a 100% pretrigger device, i.e., when the stop
signal is applied, the CCDs are stopped and the last 316 cells (632
cells for Biphase mode) are available for digital conversion and read
out.
An analog test input on the front panel provides a signal path to all
four channels for calibration purposes. When selected, the normal
inputs are internally disconnected. This signal path provides a
convenient means to verify operation of each channel.
The Model 2262 is in CAMAC format (IEEE-583). Many interfaces,
control and accessory modules exist for application-oriented system
configurations. GPIB control is available from LeCroy using the Model
8901A GPIB interface. This allows virtually any computer with a
IEEE-488 (GPIB) interface to control and read out the digitiz ers and
any associated supporting system modules. LabWindows is available to
create a user-friendly atmo sphere for the 2262 as well as to set up
a convenient vehicle for the addition of customized
user-software.
SIGNAL INPUT CHARACTERISTICS
Number of Signal Inputs: 4 in Uniphase mode; 2 in Biphase
mode.
Amplitude Range: 1.53 V p-p (1.5 mV/LSB) ±2%.
Impedance: 50 ohm ±5% DC.
Bandwidth: DC to > 40 MHz (-3 dB).
Slew Rate: > 120 V/µsec, typically 150
V/µsec.
Offset Range: Two front-panel screwdriver adjustments; one for
Channels A1 and A2 and one for B1 and B2. Operating range may be set
to cover any 1.5 V range between -1.5 V and +1.5 V.
Monitor Test Points: Two front-panel probe points for offset
monitoring. Range -1.5 V to +0 V. (The voltage measured is the most
negative point of the input voltage range.)
Overload Recovery: Recovers to ±1% of full scale within 2
samples of 2 x overdrive pulse.
Overload Protection: ±5.0 V.
Test Input: Lemo connector; impedance 50 ohm ±5%. When
selected, signal is sampled by all four channels. When no connection
is made, the digitizing of the Test input provides a convenient
ground reference for offset measurement.
OUTPUT CHARACTERISTICS
Record Length: 316 samples for Uniphase mode; 632 for Biphase
mode. Maximum data record length may be reduced by hardware option in
modules for specialized applications, reducing both conversion and
readout time.
Resolution: 1.5 mV.
Digital Format: 10 bits (1024 counts).
AC Accuracy: Ranges from ±0.25% to ±1.5% depending
upon input signal frequency and amplitude. See instruction manual for
specific performance curves.
Non-linearity: ±0.5% of best straight line fit over the
operating range.
Random Noise: < 1 count R.M.S. (With respect to best
straight line through RSO (Rate-of-Signal Offset).)
Spatial Noise: < 3 counts p-p; stable to < 1 count under
constant frequency and temperature operation. The first 2 bins of
each channel are excluded from the spatial noise specification. (With
respect to best straight line through RSO (Rate-of -Signal
Offset).)
Gain Temp Coefficient: < ±1000 ppm/°C.
Offset: Temperature coefficient: < 1 count/°C.
Droop: A linear change of offset from sample to sample.
Increases with ambient temperature and/or acquisition clock rate.
Unadjusted Droop: < 0.05 counts per sample. Adjusted Droop using
droop fine trim DACs: < 0.007 counts per bin. Fine Trim DAC Gain:
0.5 with respect to offset difference from sample 0 to sample
315.
Interchannel Matching* (All four channels): Gain < 1%
maximum, typical < 0.3%. Unadjusted Offset: < 15 counts;
Adjusted Offset using offset fine trim DACs: < 2 counts. Fine Trim
DAC Gain: 0.5.
Interchannel Isolation: 55 dB any A Channel to any B Channel;
48 dB Channel A1 to A2 and Channel B1 to B2 (at 40 MHz clock rate;
better at lower clock rates).
Digitizing Time: Approximately 1.3 msec for Biphase 632 sample
or Uniphase 316 sample conversion to digital memory. Correspondingly
less for hardware programmed shorter record lengths.
Time Base: Front-panel switch. Selects the source of the
sample clock. Internal or External.
Internal Clock: Crystal controlled oscillator operating at 80
MHz (equivalent to 40 MHz sampling in Uni-phase mode). Other
oscillator crystals may be user installed.
CLOCK IN: NIM standard input via a Lemo connector. Impedance
50 ohm. Frequency range: 8 MHz to > 80 MHz. Minimum width 5 nsec.
Every other negative going edge causes the sampling of the even
numbered inputs. Alternate negative going edges sample the odd
channels.
CLOCK OUT: NIM standard output via a Lemo connector. Impedance
50 ohm. Ungated representation of clock used to operate CCD channels
in acquisition mode. May be used as monitor or as source for another
2262 CLK IN, to achieve matching of sampling rates. Propagation delay
CLK IN to CLK OUT: 6 nsec typical.
TRIGGERING
Common Stop: NIM standard input via a Lemo connector. Impedance
50 ohm. Terminates acquisition mode on leading edge; begins data
conversion on trailing edge. Width must be greater than 1 period of
the acquisition clock or > 50 nsec; 100 µsec maximum.
Fast Clear: NIM standard input via a Lemo connector. Impedance
50 ohm. Terminates conversion in progress. Enables the unit for data
acquisition; 50 nsec minimum width.
CAMAC Trigger Output: Front-panel NIM trigger output.
Generates a NIM level of approximately 200 nsec duration upon
Connectors: All front-panel connectors are Lemo. Power: In
general, power requirements decrease as clock rate is reduced.
Examples are given below.
Packaging: In conformance with CAMAC standard for nuclear
modules (ESONE Committee Report EUR4100 and/or IEEE-583). RF-shielded
CAMAC #1 module.
Height: 221 mm; width: 17 mm; depth: 292 mm.
|
Current |
Current |
|
|
Voltage |
(40 MHz Uniphase) |
(10 MHz Uniphase) |
|
+6 V |
750 mA |
740 mA |
|
-6 V |
1225 mA |
950 mA |
|
+12 V |
600 mA |
215 mA |
|
+24 V |
190 mA |
190 mA |
|
-24 V |
70 mA |
70 mA |
|
Optional Crystal Oscillators |
|||
|
Crystal Freq. (MHz) |
Uniphase (MHz) |
Biphase (MHz) |
Part Number |
|
20 |
10 |
20 |
309 040 020 |
|
32 |
16 |
32 |
309 040 032 |
|
40 |
20 |
40 |
309 040 040 |
|
50 |
25 |
50 |
309 040 050 |
|
62.5 |
31.25 |
62.5 |
309 040 062 |
|
70 |
35 |
70 |
309 040 070 |
|
80* |
40* |
80* |
309 040 080 |
|
*Factory Supplied |
|||
CAMAC COMMANDS
C, Z: Same as F(9).
I: Inhibit Stops on all channels.
X: Indicates receipt of valid function code.
CAMAC FUNCTION CODES
F(0): Read last clock state.
F(2): Read data and advance memory pointer (subaddresses
0-7).
Subaddressing:
0 = channel A1 uniphase.
1 = channel A2 uniphase.
2 = channel B1 uniphase.
3 = channel B2 uniphase.
4,5 = channel A biphase.
6,7 = channel B biphase.
F(8): Test LAM.
F(9): Enables 2262 for data acquisition. Aborts data
conversion if in progress. Disables Q Response until new conversion
is completed. Clears LAM. Enables Stops.
F(10): Clears LAM.
F(16): Write DACs (subaddresses 0-7).
Subaddressing: 0-3 = pedestal adjustment DAC. Subaddress
corresponds to uniphase channels as in F(2) above; 4-7 = RSO
adjustment DAC. Subaddress corresponds to biphase channels as in
F(2).
F(17): Write memory pointer.
F(19)·A(0): Generate CAMAC Trigger Out.
F(19)·A(1): Select Normal/Test Inputs (W1=0=normal,
W1=1=test).
Note: The choice of test/normal inputs is NOT initialized on
power up.
F(24): Disable (mask) LAM.
F(25): Generate a conversion cycle via an internally generated
stop signal for test purposes (if stops are en abled).
F(26): Enable (unmask) LAM.