N1145 User Manual
Contents
1. Filename Number of pages Page 00115 01 N1145 MUTx 00 1145 rev0 doc 14 3 Document type Title Revision date Revision User s Manual MUT N1145 Quad Scaler and Preset Counter Timer 05 11 2003 0 1 General description 1 1 Overview CAEN Mod N1145 is a double unit NIM module that includes four independent 8 digit up counters plus a fifth 7 digit down counter that can be used either as a preset counter or as timer The counters can perform different operations and can be variously interconnected thereby making the module a flexible and powerful tool for several applications involving time frequency and ratio measurements All counters can accept either TTL or NIM inputs All control and output signals are standard NIM The maximum input frequency is 250 MHz and the minimum pulse width is 2 ns for the up counters and respectively 80 MHz and 3 ns for the down counter All input and output connectors as well as all the control switches are located on the front panel All input and output connectors are LEMO 00 type NPO Filename Number of pages Page 00115 01 N1145 MUTx 00 1145 revO doc 14 4 Document type User s Manual MUT Title 1 2 Front panel INPUT CONNECTOR GATE BRIDGED CONNECTORS INPUT CONNECTOR GATE CONNECTOR CARRY CONNECTOR INPUT CONNECTOR GATE BRIDGED CONNECTORS INPUT CONNECTOR GATE CONNECTOR CARRY CONNECTOR RESET CONNECTOR INPUT CONNECTOR OUTPUT CONN2. even if the counter is already zero and thus the cycle completed In REPEAT mode a few seconds after zero is reached the counter re triggers itself automatically by performing an automatic LOAD and a new cycle is restarted The automatic LOAD takes place every 2 seconds after every cycle end This procedure is repeated indefinitely anyway the LOAD button allows to restart the counter at any time The LOAD NIM TTL is always useless in REPEAT mode Note that by connecting the END MARKER output to the LOAD input the counter is cycled without the time delay of the REPEAT mode Important Note one or more of the following operations may lead the Section 5 to an incorrect operation use of an external clock with frequency larger than 80 MHz The use of an external clock with pulse width shorter than 3 ns The variation during the counter operation of the external clock frequency switching from internal clock to external or vice versa In any case the counter normal operation is recovered by performing a manual electrical LOAD Filename Number of pages Page 00115 01 N1145 MUTx 00 1145 revO doc 14 10 Document type Title Revision date Revision User s Manual MUT N1145 Quad Scaler and Preset Counter Timer 05 11 2003 0 g E NIM INPUT LOAD 3ns min DISPLAY DATA o E 4 1 O
3. is then given by fi Mc Nt where Mg is the number of pulses received by the Counter while GATE is active 4 4 Divider Section 5 can also be used as a divider of an external input sequence For that purpose e connect the END MARKER output to the LOAD input e Select the input output ratio R by setting the thumb wheel switches e Connect the external input at the section 5 input port and pick the NIM output from the OUT ports which is a pulse generated every R pulses at the input 4 5 Delay unit Section 5 can also be used to generate a delayed pulse at the END MARKER output or transition at the OUT ports An absolute delay can be obtained with section 5 in TIMER Mode The duration of the delay is Td Nr actually the time interval between the LOAD signal leading edge and the leading edge of the END MARKER where N is the preset value on the Thumb wheel Switch display and is the internal clock period The time delay is the elapsed time between the time of the leading edge at the LOAD input and leading edge either at the END MARKER output See the next section for accuracy With the counter in COUNTER Mode a relative delay in terms of number of pulses can be obtained between the NIM TTL input and the END MARKER after the preset number of input pulses have been counted 4 6 Measurement accuracy For the previous applications it is important to remember that with any measurement made with a counter on a periodic wavefor
4. ECTOR SOURCE SELECT N1145 Quad Scaler and Preset Counter Timer Revision date Revision 05 11 2003 0 mm yp y Mod N1145 QUAD SCALER AND PRESET COUNTER TIMER MODE SELECTION SWITCH GT CLR NORMAL GATE CH1 MODE SELECTION SWITCH GATE CARRY 4 2 NORMAL GATE GT CLR CH2 MODE SELECTION SWITCH NORMAL GATE CH3 GT CLR MODE SELECTION SWITCH NORMAL GATE CH4 GT CLR RESET CH1 CH2 CH3 CH4 RESET PUSHBUTTONS END MARKER SINGLE REPEAT SWITCH END MARKER CONNECTOR LOAD SWITCH FREQUENCY SELECT SWITCH NPO 00115 01 N1145 MUTx 00 Filename n1145 rev0 doc 14 5 CONNECTOR LOAD PUSHBUTTON THUMB SWITCHES Fig 1 1 Mod N1145 Front Panel Number of pages Page Document type Title User s Manual MUT N1145 Quad Scaler and Preset Counter Timer
5. Revision date Revision 05 11 2003 0 2 Technical specifications 2 1 2 1 2 2 Packaging The Model N1145 is housed in a double width NIM module Power requirements 6 V 700 mA 6 V 900 mA Front panel I O connections SECTIONS 1 AND 3 INPUTS GATE SECTIONS 2 AND 4 INPUTS GATE CARRY SECTIONS 1 2 3 and 4 RESET SECTION 5 INPUTS LOAD OUT NPO 00115 01 N1145 MUTx 00 C NIM level 1 800 mV TRUE Filename n1145_rev0 doc 1 accepts both NIM and TTL signals 50 impedance 2 NIM TTL bridged input ports high impedance internally connected Free port must be terminated on 500 1 accepts both NIM and TTL signals 50 Q impedance one NIM TTL input 50 impedance one NIM output Generates a pulse when counter has fully cycled transition 99 999 999 to 0 one NIM TTL input 50 O impedance clears sections 1 to 4 Same effect is obtained for each section with the individual RESET pushbuttons 1 accepts both NIM and TTL signals 50 Q impedance one NIM TTL input 50 O impedance Loads counter with value preset on the thumb wheel switch digits same effect with LOAD pushbutton 2 NIM outputs these are true as long as counter contents are different from zero Number of pages Page 14 6 Document type Title Revision date Revision User s Manual MUT N1145 Quad Scaler and Preset Counter Timer 05 11 2003 0 END MARKER one NIM output a pulse generated when
6. Technical Information Manual Revision n 0 5 November 2003 MOD N1145 QUAD SCALER AND PRESET COUNTER TIMER NPO 00115 01 N1145 MUTx 00 CAEN will repair or replace any product within the guarantee period if the Guarantor declares that the product is defective due to workmanship or materials and has not been caused by mishandling negligence on behalf of the User accident or any abnormal conditions or operations CAEN declines all responsibility for damages or injuries caused by an improper use of the Modules due to negligence on behalf of the User It is strongly recommended to read thoroughly the CAEN User s Manual before any kind of operation CAEN reserves the right to change partially or entirely the contents of this Manual at any time and without giving any notice Document type Title Revision date Revision User s Manual MUT N1145 Quad Scaler and Preset Counter Timer 05 11 2003 0 TABLE OF CONTENTS 1 GENERAL DESCRIPTION iiscssssssscssssesenssssstecsesvcesssvessosiuvensessacsdscbescossensessescessebsacsseviaseodsvdeessbestossevestecsooss 4 ld SOONER VIEW te i ete ES 4 T2 PRONT PAN PRTERTERR H 5 2 TECHNICAL SPECIFICATIONS eo eh Vaso seo rea beo soe eU do aa eb esaet teo oo de e ep eU gea ep Eod 6 2 PACKAGING eeeeeI I e eme emememen nnnm ennt ese ese ese ese ese ese ese ese ese ese sesesesesese sese ses sees eseses esee eset etes esee ess
7. UT END MARKER Ne Trimmer adjustable E Fig 3 1 Section 5 Timing Diagram NPO Filename Number of pages Page 00115 01 N1145 MUTx 00 1145 revO doc 14 11 Document type Title Revision date Revision User s Manual MUT N1145 Quad Scaler and Preset Counter Timer 05 11 2003 0 4 Operating modes 4 1 4 2 4 3 NPO Gated up counting When in NORMAL MODE the counters sections 1 to 4 do not require a GATE input However when in GATE or GATE CLEAR mode a NIM TTL signal must be supplied at the GATE input of each counter used NOTE when using NIM input signals this signal has to be terminated with 50 Q impedance at the other GATE bridged input on sections 1 or 3 A single GATE signal can be sent in parallel to two channels via cables if the last section is either 2 or 4 then this also provides the correct 50 Q cable termination For example sections 1 and 2 can share a GATE by feeding the external GATE signal to the GATE input of section 1 and then connecting a cable between the other GATE output of section 1 to the GATE input of section 2 which has a 50 O impedance It is also possible to connect three sections for instance 1 with 3 and then 3 with 2 or 4 via cables in order to send them a single external GATE input The OUT signal of section 5 can be used as the GATE input to the counters The double OUT connector permits parallel GATE feeding of all four sections
8. as described above 16 or 24 Digit Up Counting It is possible to increase the up counting range to 16 or 24 digits by using the CARRY outputs of sections 2 and 4 For instance 16 digit up counting is obtained by connecting the CARRY output of section 2 to the input of section 1 When the counter of section 2 has fully cycled transition 99 999 999 to zero the CARRY output supplies a NIM input pulse to section 1 and so on Thus section 1 will show the most significant digits and section 2 the least significant digits of the counting operation Similarly for 24 digit up counting the CARRY output of section 2 may be connected to the input of section 4 the CARRY output of section 4 may then be fed to the input of section 1 or 3 Frequency measurements This is a way of making relative frequency measurements By using section 5 in TIMER MODE it is possible to make a frequency measurement For that purpose e select the clock rate fal Filename Number of pages Page 00115 01 N1145 MUTx 00 n1145_rev0 doc 14 12 Document type Title Revision date Revision User s Manual MUT N1145 Quad Scaler and Preset Counter Timer 05 11 2003 0 with the TIMER switch t 1 us or 1 ms e select a value N for instance a power of 10 with the thumb wheel switches The measurement time is then Tj Nr e use the OUT signal as the GATE input to the selected section 1 to 4 Counter s operating in GATE CLEAR mode The external input frequency
9. ection 1 and 3 2 bridged high impedance NIM TTL inputs Lacus Section 2 and 4 50 O impedance NIM TTL input lozi 1 NIM TTL input loads counter with value set on thumb wheel switches min FWHM 3 ns Carr std NIM level two sections can be cascaded by feeding first Y CARRY into the input of the second section thereby making a Section sand 4 16 digit counter Control 1 NIM output a pulse is generated when the counter reaches outputs End marker zero Pulse width can be adjusted by turning the front panel trimmer 50 ns to 1 us Out 2 NIM outputs are true as long as counter s value differs from zero Sections 1 to 4 250 MHz Max frequency Section 5 80 MHz FWHM is 2 2 ns when GATE CLEAR mode see 3 1 is used NPO 00115 01 N1145 MUTx 00 Filename n1145_rev0 doc Number of pages Page 14 8 Document type Title Revision date Revision User s Manual MUT N1145 Quad Scaler and Preset Counter Timer 05 11 2003 0 3 Principles of operation 3 1 3 2 Sections 1 to 4 The 8 digit up counters can operate in three distinct modes which are NORMAL Free running The counter is incremented by the input pulses GATE The counter is incremented by input pulses only if the GATE input is true GATE CLEAR Same as GATE mode but the leading edge of the GATE input clears the counter The modes are manually selectable for each section by the relevant switches see 2 3 on the front panel The up counters are
10. es esee 6 21 2 POWER REQUIREMENTS etre e PEE ERE Ur o e EC CIE E A i 6 2 2 FRONT PANEL I O 6 23 FRONT PANEL SWITCHES 7 24 TECHNICAL SPECIFICATION TABLE et cobece eeu eg eue pe aene eer eee eeu v 8 3 PRINCIPEES OP OPERATION wa aede see aee ro s CUN Coe ee Pee ove aue oU eaae Ee 9 Bele SECTIONS TO sr nt e etat ne Ea 9 3 2 SECTION e ee eet ee e oec tea eec ooo ee ee ees 9 4 OPERATING MODES 12 41 GATEDU P COUNTING eet eerte etre ee dete tede eee decedere ode eee bete decet rera 12 4 2 16 OR 24 DIGIT UP COUNTING eeeceeeeenennn e 12 4 3 FREQUENCY MEASUREMENTS ccsssscccccceessssscecececsesssseaececececsessaaecececsesenseaececececsensaaececececeeseaaeaeceeeesensas 12 qu JDEIDERSS Gueule eee mic eK Unix UNE 13 5 DELAY UNIT zuerst tee a e ete tb isee 13 4 6 MEASUREMENT e n ene n nnn nnne nnn n uen EEEE RESES spese nasa nn n eeaeee 13 LIST OF FIGURES 1 1 MOD 145 nn rrr De ee ee e SN EE ERR eee 5 3 1 SECTION TIMING DIAGRAM 11 LIST OF TABLES TABLE 2 1 MOD N1145 TECHNICAL FEATURES cccccccccccccccccccesccesesesesesesesesesesesesesesesesesesesesesceesesessseseseesesesesenees 8 NPO
11. m there is always an intrinsic uncertainty of one pulse This is due to the fact that depending on the position of the start of the measurement window with respect to the period of the waveform one pulse may or may not be totally included and thus counted for This also applies to the uncertainty of the selection of the reference time window NPO Filename Number of pages Page 00115 01 N1145 MUTx 00 1145 revO doc 14 13 Document type Title Revision date Revision User s Manual MUT N1145 Quad Scaler and Preset Counter Timer 05 11 2003 0 The uncertainty of the measurement of an absolute time delay is therefore equal to the clock period For frequency measurements it is Afi fmax fmin Mc Nr Mc 1 Nz 1 Nz where Afj is the absolute frequency uncertainty The relative frequency uncertainty is then Afi 1 Mc and since for a given constant frequency Mc Nf is proportional to N the percent accuracy is increased by increasing N NPO Filename Number of pages Page 00115 01 N1145 MUTx 00 1145 revO doc 14 14
12. ognised by the module Filename Number of pages Page 00115 01 N1145 MUTx 00 n1145 revO doc 14 Document type Title Revision date Revision User s Manual MUT N1145 Quad Scaler and Preset Counter Timer 05 11 2003 0 NPO input pulse the OUT ports become true The counter is then decremented by the input pulses until zero is reached At the trailing edge of the last input pulse the OUT outputs are reset to FALSE 0 V the END MARKER output generates a NIM pulse whose length can be adjusted between 50 ns and 1 us by acting on the trimmer next to the END MARKER connector this signal is retriggerable thus it can be extended while active by another completed cycle If the END MARKER is used for retriggering purposes it is sent to the LOAD connector a delay larger than the END MARKER duration is required between these connectors This arrangement allows direct use of the OUT ports as GATE inputs to the counters of section 1 to 4 CYCLING of Section 5 is controlled by the SINGLE REPEAT switch which is labelled SGL REP In SINGLE mode the selected function PRESET COUNTER or TIMER is performed only once until zero is reached In order to restart the counter a new load operation is required Actually when using the LOAD button the counter can be restarted even BEFORE zero is reached The LOAD NIM TTL signal is disabled during counting After a LOAD via pushbutton the unit requires 80 ns at least before accepting LOAD pulses
13. reset to zero either manually individually for each section by acting on the RESET pushbuttons or electrically common to all sections by means of a NIM TTL pulse on the RESET input Sections 1 and 3 have two NIM TTL high impedance GATE bridged inputs which are internally connected a NIM TTL input must be terminated with a 50 Q impedance at the other port Sections 2 and 4 have one 50 Q GATE NIM TTL input and one CARRY NIM output The CARRY output generates a NIM pulse when the counter has fully cycled transition from max counter value to zero This can be used to extend the counters range by cascading sections as shown later Section 5 The fifth counter is a 7 digit counter that can operate as a PRESETTABLE DOWN COUNTER or as a TIMER Either mode is selected by the manual SOURCE SELECT switch labelled COUNTER TIMER In COUNTER mode the counter is decremented by the external NIM or TTL input pulses In TIMER mode the counter is decremented by an internal clock regardless the input pulses The frequency is selectable by acting on the TIMER switch and can be set to 1 KHz 1 ms or to 1 MHz 1 us In either mode the counter must be initally preset to the desired value by acting on the Thumb wheel switches and then by loading the datum either manually with the LOAD pushbutton or electrically with the LOAD NIM TTL pulse At the trailing edge of the first NPO Any value can be loaded except Zero which is not rec
14. the counter 2 3 NPO contents become zero Pulse width is adjusted with trimmer between 50 ns and 1 us All connectors are LEMO 00 type Front panel switches MODE SELECTION SWITCHES Section 1 4 Function they allow to select the operating mode see 3 1 RESET PUSHBUTTONS Section 1 4 Function they allow to clear the relevant section see 3 1 SOURCE SELECTION SWITCH Section 5 Function it allows to select the operating mode see 3 2 SINGLE REPEAT SWITCH Section 5 Function it allows to select the counter cycling see 3 2 FREQUENCY SELECTION SWITCH Section 5 Function it allows to select the internal clock frequency see 3 2 LOAD PUSHBUTTON Section 5 Function it allows to load the thumb switches value see 3 2 THUMB SWITCHES Section 5 Function they allow to set the counter timer datum see 3 2 Filename Number of pages Page 7 00115 01 N1145 MUTx 00 1145 revO doc 14 Document type Title Revision date Revision User s Manual MUT N1145 Quad Scaler and Preset Counter Timer 05 11 2003 0 2 4 Technical specification table Table 2 1 Mod N1145 Technical Features Packaging Two units wide NIM module RNE 1 NIM TTL level input per section 50 Q impedance min FWHM 2 ns sections 1 4 3 ns section 5 1 NIM TTL input 50 impedance clears sections from 1 to 4 Comm Reset min FWHM 3 ns Control Gate S
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