CN100434899C - Flight time detection method and device for aerosol particle spectrum (mass spectrum) - Google Patents

Abstract

The present invention discloses a flight time detection method and a device for aerosol particle spectrums (mass spectrums). Flight time scattering peak signals generated by avalanche diode detection circuits are delayed by a delay circuit, and then, autocorrelation and / difference calculation is carried out by an adder and a subtracter; the flight time scattering peak signals are sent to a band-pass filter; gate control (GATE) signals and differential (DIFF) signals are obtained after the flight time scattering peak signals are amplified by a high-speed clamping amplifying circuit and a high speed amplifier; modes of the scattering peak signals of aerosol particles are recognized by a high-speed programmable circuit, and the gate control (GATE) signals and differential (DIFF) signals are output by a double-port memory circuit. The present invention can recognize the modes at high speed, can detect the pulse width of double peaks of scattering peaks and the peak strength with high accuracy, and can store all the information of aerosol particle spectrums (mass spectrums).

Description

Aerosol particle spectrum (mass spectrum) flight time detection method and device

Technical field

The invention belongs to environmental optics monitoring, person in electronics, specifically is a kind of aerosol particle spectrum (mass spectrum) flight time detection method and device.

Prior art

When the light scattering method of employing aerodynamic principle is measured the particle diameter spectrum distribution of airborne aerosol particle thing, tighten from two when the aerosol particle thing and to produce the bimodal signal that intensity becomes normal distribution when flying over the laser beam of leaning on, splitblip width value wherein, being the flight time TOF of aerosol particle thing through two bundle laser beam, is exactly the aerodynamic diameter information of this aerosol particle thing; And bimodal pulse strength can be revised the optical diameter information of particulate.The bimodal signal that particulate forms just like accompanying drawing 1 particulate through shown in the signal waveform that laser beam produces: the gasoloid shown in three peak-to-peak signals when effectively the particulate shown in the pattern C of the bimodal signal of particulate, accompanying drawing 1 takes place to overlap shown in the Mode B of the unimodal signal of the particulate shown in the Mode A of accompanying drawing 1, accompanying drawing 1, the pattern D of accompanying drawing 1 exceeds the macroparticle signal of measurement range.The flight time of particulate generally at 500ns between the 4000ns, belong to high speed signal.At present high speed acquisition signal and mainly be to adopt high-speed a/d card change-over circuit module with the collecting of flight time signal integrity to the method for signal identification carries out the identification of pattern, the calculating of pulsewidth, the processing of peak strength.Next is by setting threshold voltage, make two peak values of bimodal signal all be slightly larger than threshold voltage, and two burst pulses of corresponding and two peak values that bimodal signal and threshold voltage obtain through comparator circuit are just corresponding to bimodal pulsewidth, as shown in Figure 2.

Pattern, record scattering peak value and record-setting flight time method for above-mentioned record scattering peak signal, mainly there is following shortcoming: at first, the high-speed a/d capture card is gathered the method for complete signal, though reproduction original signal that can be more complete is to be undertaken by software to the intensity sampling of pattern-recognition, pulse width and the peak value of detected each aerosol particle subsignal.Although present A/D slewing rate can reach the ns level, cost is than higher.Simultaneously, because the signal of each particle all must carry out same software processes, and carries out statistical counting to the particulate of identical flight time, scattered light intensity,, can not continue the signals collecting of high speed because of the restriction of the interface rate of PC.Secondly, the pattern-recognition of carrying out the scattering peak signal with the method for setting threshold voltage is fairly simple, but this method is subjected to the influence of threshold voltage setting value, can not accurately measure the pulse width (flight time of particle) of bimodal signal, and can not be effectively and the intensity of collection peak value at a high speed.

Summary of the invention

In order to overcome the defective of measuring in the said method high-speed, that owe pinpoint accuracy of owing, the object of the present invention is to provide the measuring method device of a kind of atmospheric aerosol particle grain spectrum (mass spectrum) flight time, based on the autocorrelation principle of scattering peak signal, can carry out pattern-recognition at a high speed, detect the splitblip width and the peak strength of scattering peak and store the complete circuit of aerosol particle seed spectrum (mass spectrum) full detail accurately.

Concrete technical scheme of the present invention is as follows:

Aerosol particle spectrum (mass spectrum) flight time detection method,

After the flight time scattering peak signal process delay circuit delays by the generation of avalanche diode detection circuit, obtain two groups of autocorrelation signals with same phase difference,

Wherein one group of phase differential signal that is 300ns is delivered to totalizer and is carried out auto-correlation and computing, obtain auto-correlation and signal, deliver to bandpass filter (4), with the effective filtering of spurious signal, again the relevant and signal after the filtering is amplified and clamper through high speed clamper amplifying circuit, compare with the threshold signal of setting by comparator circuit again, obtain gate GATE signal, gate GATE signal and difference DIFF signal are through level conversion, deliver to high speed programmable circuit, carry out the pattern-recognition of particulate scattering peak signal;

The signal that other one group of phase differential is 300ns is delivered to subtracter and is carried out the auto-correlation difference operation, deliver to bandpass filter (11) filtering again, through band-pass filter, obtain the auto-correlation difference signal, again after high speed amplifier amplifies, delivering to comparator circuit compares with zero level, obtain difference DIFF signal, be input to the ECL high-speed counting circuit, with the starting of two negative edges control high precision ECL counters of DIFF signal with stop, through the flight time digital signal after the processing of ECL high-speed counting circuit, deliver to high speed programmable circuit;

Simultaneously original scattering peak signal keeps the peak level of scattering peak signal through high-performance amplification, absolute value detecting circuit, converts the digital signal of scattered light intensity again to through the high-speed parallel A/D change-over circuit of high speed programmable circuit control;

High speed processing circuit with two extensive programmable chips compositions of high speed, the flight time T_BUS of aerosol particle spectrum (mass spectrum) and the mode record at scattering peak value SS_BUS and particle scattering peak are gone in the dual port memories chip, data slice (21) is mainly as the identification of particle signal and the buffer register of data, address slice (22) is mainly with flight time and scattered light intensity digital data conversion position corresponding memory addresses spatial data, and the read-write of dual port memories control, the identification particulate scattering peak pattern information that data slice 21 is correct, and allow address slice (22) latch flight time and scattered light intensity, obtain the proper memory address information, data slice (21) is read the content of this internal storage location in the data slice 16Bit register and is gone, and the content after will handling is deposited go back to the raw address space, the flight time and the scattered light intensity information of preservation aerosol particle spectrum (mass spectrum).

Described aerosol particle spectrum (mass spectrum) flight time detection method, the low-end cut-off frequency that it is characterized in that bandpass filter (4) is arranged on 1KHz, high-end cutoff frequency is arranged on 500KHz, the low-end cut-off frequency of bandpass filter (11) is arranged on 1KHz, and high-end cutoff frequency is arranged on 3.16MHz.

Aerosol particle spectrum (mass spectrum) flight time pick-up unit, it is characterized in that the scattered light peak signal that is obtained by detector is input to stepping time delay module circuit, it is the analog addition circuit that core is formed that one group two road signal wires connect with OP467 (U1A), the analog addition circuit, with OP467 (U1C) is the active filter circuit of core, CLC501 (U2, U3) and the high speed clamping circuit clamper formed of TLE2081 (U6), high speed comparator circuit HM96687 (U7A) connects successively, and set level Gate_Set for high speed comparator circuit HM96687 (U7A in the accompanying drawing 8) provides thresholding, high speed comparator circuit HM96687 output ECL level and signal (GATE and/GATE);

Other one group of two road signal wire, series connection is the analog subtraction circuit that core is formed with OP467 (U1B), the filtering circuit filtering that capacitance-resistance inductance etc. is formed of connecting successively again of analog subtraction circuit, with CLC501 (U4) is the high speed amplifying circuit of core, high speed comparator circuit HM96687 (U7B), and for high speed comparator circuit HM96687 provides level "0" relatively, obtain the ECL level differential signal (DIFF and/DIFF);

The ECL level and signal (GATE and/GATE) and difference signal (DIFF and/DIFF) output line meets ECL-TTL level shifting circuit 10H125 (U16), output Transistor-Transistor Logic level and signal (GATE_T) and zero cross signal (ZC).The GATE_T signal is connected the high speed processing circuit that high speed field programmable gate function MACH435 (U8, U9) forms with the ZC signal wire;

The ECL level and signal (GATE, / GATE) and difference signal (DIFF, / DIFF) the double D trigger 10H131 (U17) of output line connection ECL level is the logical circuit of core, connect again 20 that 8 digit counter 10H137 (U20) and Transistor-Transistor Logic level 12 digit counter 74HC4040 (U24) combine high-speed, the flight time counting circuit of big counting region, with frequency generator TQ2061 (U19) and 25MHz crystal oscillator (U25) is the High Speed ECL level clock generating circuit of core, the ECL clock signal up to 500MHz that produces can provide the temporal resolution up to 2ns, this clock is supplied with aforementioned flight time counting circuit, and the flight time counting circuit is connected with the high speed processing circuit.

Detector peak signal output line connects by OPA665 (U11, U12) and low pressure reduction and recovers high precision, the high-speed absolute value detecting circuit that schottky diode MMBD301 related elements such as (CR301, CR302) is formed soon, connecting with high-speed parallel A/D conversion chip again is core, be aided with the A/D change-over circuit that low noise high speed amplifier LM358 (U8B, U14A, U14B) and low noise high speed amplifier TLE2074 (U13A, U13B) form, the A/D change-over circuit is connected with the high speed processing circuit.

High speed processing circuit so that two extensive programmable chip MACH435 of high speed (U8, U9) form connects two-port RAM chip CY7C028 (U10).

The invention provides and a kind ofly can discern the scattering peak pattern at a high speed, detect the wide value of pulse of general bimodal signal, the circuit arrangement of peak strength value accurately.Use autocorrelation principle among the present invention, adopted high-speed programmable device, High Speed ECL circuit, simulation stepping correlation delay element, high speed operation amplifier and high-speed comparator etc.

The present invention can not only can be applied in the atmospheric aerosol aerodynamics grain spectrometer, is used for discerning at a high speed the scattering peak pattern, detects the wide value of pulse, the peak strength value of scattering peak signal accurately; Simultaneously, this circuit can be handled the general original signal that possesses one of following feature:

1, the splitblip width of original signal is one of characteristic information, needs high-speed record;

2, the intensity of original signal is one of characteristic information, needs high-speed record;

3, the peak pattern of original signal need be discerned and record.

When having the signal demand collection of one of above-mentioned feature, all can adopt the circuit arrangement of thinking of the present invention.

Innovative point of the present invention is:

The pattern-recognition of A, auto-correlation scattering peak

The present invention is with the raw scattered peak-to-peak signal, through suitable delay, carry out auto-correlation and computing and auto-correlation difference operation then, relevant and the signal that draws can effectively filtering spurious signal, and the relevant difference signal then is used for discerning the pattern of scattering peak and is used for detecting pulse width between bimodal.This processing mode can be handled the scattering peak signal mode efficiently.

B, high-speed

The present invention comes tupe identification by adopting high-speed programmable logical circuit (15ns), the minimum value 500ns of former flight time less than particle.Relevant operational amplifier, comparer etc. all adopt high speed device.Digital processing circuit generally adopts high speed TTL circuit, High Speed ECL circuit.Whole flight time pick-up unit processing procedure is based upon on the high-speed hardware, and processing speed is high.

C, pinpoint accuracy

The counting circuit of flight time mainly adopts the ECL high speed circuit, and counting clock pulse uses the ECL level, and up to 500MHz, temporal resolution reaches 2ns.

The invention effect

This circuit has following characteristics: 1, adopt the High Speed ECL counting circuit accurately to measure the flight time, resolution reaches 2ns, the degree of accuracy height; 2, adopt the high-speed programmable device to discern the pattern of scattering peak signal, control the collection of scattered light signal and can produce the control signal of storage, the processing speed height; 3, adopt high precision peak holding circuit and parallel at a high speed A/D change-over circuit, also accurate at a high speed sampled peak signal; 4, the identification of pattern and parameter be measured as concurrent working, the efficient of processing is high.

Description of drawings

The signal waveform that Fig. 1 particulate produces through laser beam.

The bimodal narrow pulse waveform of Fig. 2.

Fig. 3 is based on auto-correlation splitblip signature detection circuit block diagram 1.

Fig. 4 is based on auto-correlation splitblip signature detection circuit block diagram 2.

Fig. 5 high speed programmable circuit interior block diagram.

Fig. 6 high speed programmable circuit work-based logic process flow diagram.

The bimodal signal autocorrelation treatment conversion of Fig. 7 figure.

Fig. 8 is electronic circuit Fig. 1.

Fig. 9 is electronic circuit Fig. 2.

Figure 10 is electronic circuit Fig. 3.

Figure 11 is electronic circuit Fig. 4.

Embodiment

In accompanying drawing 3 and the accompanying drawing 4, the flight time scattering peak signal 1 that is produced by the avalanche diode detection circuit (in the accompanying drawing 7 shown in the waveform A) postpones through delay circuit 2, obtains two groups of autocorrelation signals with same phase difference (in the accompanying drawing 7 shown in the waveform B).The value of the time delay of delay circuit is about about half of short pulse duration 500ns, gets about 300ns.

Wherein one group of phase differential signal that is 300ns is delivered to totalizer 3 and is carried out auto-correlation and computing, obtains auto-correlation and signal, delivers to bandpass filter 4.The low-end cut-off frequency of bandpass filter 4 is arranged on 1KHz, and high-end cutoff frequency is arranged on 500KHz, can be with the effective filtering of spurious signal, obtain heterocoelous relevant and signal (in the accompanying drawing 7 shown in the waveform C).Relevant and signal amplifies and clampers through high speed clamper amplifying circuit 5, compares with the threshold signal 6 of setting by comparator circuit 7 again, obtains gate (GATE) signal 8 (in the accompanying drawing 7 shown in the waveform E).GATE signal 8 offers high speed programmable circuit 9, helps to carry out the pattern-recognition of particulate scattering peak signal.Being identified under the GATE signal 8 effective situations of pattern carried out, and the interference that can avoid noise signal to bring makes the work of circuit efficient high-speed ground.

The signal that other one group of phase differential is 300ns is delivered to subtracter 10 and is carried out the auto-correlation difference operation, delivers to bandpass filter 11 filtering again.The low-end cut-off frequency of bandpass filter 11 is arranged on 1KHz, and high-end cutoff frequency is arranged on 3.16MHz.Through bandpass filter 11 filtering, obtain auto-correlation difference signal (in the accompanying drawing 7 shown in the waveform D), after high speed amplifier 12 amplifies, deliver to comparator circuit 14 and compare again with zero level 13, obtain difference (DIFF) signal 15 (in the accompanying drawing 7 shown in the waveform F), offer high speed programmable circuit 9.The number that high speed programmable circuit 9 is reduced to low level zero crossing by the high level of differential signal is discerned the pattern of scattering peak signal.Unimodal signal has only a negative edge, and the negative edge of bimodal signal has two, and the negative edge of the above signal in three peaks has more than three.The signal that identification form peak-to-peak signal that like this can be correct, bimodal signal and three peaks are above.Time between two negative edges of the corresponding exactly and DIFF signal 15 of the pulse width of bimodal signal simultaneously.With the starting of two negative edges control high precision ECL counters 20 of DIFF signal 15 with stop, then can measuring the flight time of particle accurately.The resolution of High Speed ECL counting circuit is guaranteed the accurate measurement of flight time up to 2ns.Through the flight time digital signal after the foregoing circuit processing, deliver to high-speed programmable device 9.

Simultaneously original scattering peak signal 1 keeps the peak level of scattering peak signal through high-performance amplification, absolute value detecting circuit 16, converts the digital signal of scattered light intensity again to through the high-speed parallel A/D change-over circuit 17 of high speed programmable circuit 9 controls.High speed programmable circuit 9 is made up of the high-speed programmable device of two 15ns, and the internal frame diagram of the high speed processing circuit high speed programmable circuit of forming with two extensive programmable chip MACH435 of high speed (U8, U9 in the accompanying drawing 9) as shown in Figure 5.Data slice 21 is main as the identification of particle signal and the buffer register of data.Address slice 22 is mainly with flight time and scattered light intensity digital data conversion position corresponding memory addresses spatial data, and the read-write of dual port memories control, is called address slice.The identification particulate scattering peak pattern information that data slice 21 is correct, and allow address slice 22 latch flight time and scattered light intensity, obtain the proper memory address information.Data slice 21 is read the content of this internal storage location in the data slice 16Bit register and is gone, and the content after will handling is deposited go back to the raw address space, the flight time and the scattered light intensity information of preservation aerosol particle spectrum (mass spectrum).Address slice 22 and data slice 21 combine, and the pattern-recognition, flight time measurement, scattered light intensity of finishing particulate measure, the storage of complete particle information, functions such as the operation of mass storage.The operation logic of high speed programmable circuit as shown in Figure 6.

Circuit is described

As shown in Figure 8, the scattered light peak signal that is obtained by detector postpones through stepping time delay module circuit (D100 in the accompanying drawing 8), obtains four road signals about two groups of phase differential 300ns.

One group of signal wherein, warp is the analog addition circuit addition that core is formed with OP467 (U1A in the accompanying drawing 8), warp is the active filter circuit filtering of core with OP467 (U1C in the accompanying drawing 8) again, through the high speed clamping circuit clamper of forming by CLC501 (U2, U3 in the accompanying drawing 8) and TLE2081 (U6 in the accompanying drawing 8), last set level Gate_Set relatively by high speed comparator circuit HM96687 (U7A in the accompanying drawing 8) with thresholding, obtain the ECL level and signal (in the accompanying drawing 8 GATE with/GATE).

Other one group of signal, warp is that the analog subtraction circuit that core is formed subtracts each other with OP467 (U1B in the accompanying drawing 8), the filtering circuit filtering of forming through capacitance-resistance inductance etc. again, be the high speed amplifying circuit amplification of core then through CLC501 (U4 in the accompanying drawing 8), once more after the filtering, deliver to high speed comparator circuit HM96687 (U7B in the accompanying drawing 8) and level "0" relatively, obtain the ECL level differential signal (in the accompanying drawing 8 DIFF and/DIFF).

As shown in Figure 11, the ECL level and signal (GATE and/GATE) and difference signal (DIFF and/DIFF) be converted to Transistor-Transistor Logic level through ECL-TTL level shifting circuit 10H125 (U16 in the accompanying drawing 11) and signal (GATE_T in the accompanying drawing 11) and zero cross signal (ZC in the accompanying drawing 11).GATE_T signal and ZC signal are sent in the high speed processing circuit that high speed field programmable gate function MACH435 (U8, U9 in the accompanying drawing 9) forms and handle.

The ECL level and signal (GATE, / GATE) and difference signal (DIFF, / DIFF), double D trigger 10H131 (U17 in the accompanying drawing 11) by the ECL level is the logical circuit of core, produces the 8 digit counter 10H137 (U20 in the accompanying drawing 11) of control ECL level and the flight time counting circuit of 20 high-speed, big counting regions that Transistor-Transistor Logic level 12 digit counter 74HC4040 (U24 in the accompanying drawing 11) combine.With frequency generator TQ2061 (U19 in the accompanying drawing 11) and 25MHz crystal oscillator (U25 in the accompanying drawing 11) is the High Speed ECL level clock generating circuit of core.The ECL clock signal up to 500MHz that produces can provide the temporal resolution up to 2ns, and this clock is supplied with aforementioned flight time counting circuit, makes the measurement of flight time have very high precision.The flight time digital quantity T_BUS of flight time counting circuit record delivers to the high speed processing processing of circuit in the accompanying drawing 9 equally.

Simultaneously, peak signal is via OPA665 (U11 in the accompanying drawing 10, U12) reach low pressure reduction and recover schottky diode MMBD301 (CR301 in the accompanying drawing 10 soon, the high precision formed of related elements such as CR302), high-speed absolute value detecting circuit sampling also keeps, delivering to high-speed parallel A/D conversion chip is core, be aided with low noise high speed amplifier LM358 (U8B in the accompanying drawing 10, U14A, U14B) and low noise high speed amplifier TLE2074 (U13A in the accompanying drawing 10, U13B) high precision of Zu Chenging, at a high speed, low noise A/D change-over circuit obtains the digital signal SS_BUS of scattered light peak signal strength.This SS_BUS digital signal is delivered in the high speed processing circuit in the accompanying drawing 9 and is handled.

As shown in Figure 9, high speed processing circuit so that two extensive programmable chip MACH435 of high speed (U8, U9 in the accompanying drawing 9) form removes the flight time T_BUS of aerosol particle spectrum (mass spectrum) and the mode record at scattering peak value SS_BUS and particle scattering peak in two-port RAM chip CY7C028 (U10 in the accompanying drawing 9).

Claims (3)

1, aerosol particle spectrum/mass spectrum flight time detection method,

After the flight time scattering peak signal process delay circuit delays by the generation of avalanche diode detection circuit, obtain two groups of autocorrelation signals with same phase difference,

Wherein one group of phase signal signal that is 300ns is delivered to totalizer and is carried out auto-correlation and computing, obtain auto-correlation and signal, deliver to bandpass filter (4), with the effective filtering of spurious signal, again auto-correlation after the filtering and signal are amplified and clamper through the high speed clamping circuit, compare with the threshold signal of setting by comparator circuit again, obtain gate GATE signal, gate GATE signal and difference DIFF signal are through level conversion, deliver to high speed programmable circuit, carry out the pattern-recognition of particulate scattering peak signal;

The signal that other one group of phase differential is 300ns is delivered to subtracter and is carried out the auto-correlation difference operation, deliver to bandpass filter (11) filtering again, through bandpass filter (11) filtering, obtain the auto-correlation difference signal, again after high speed amplifier amplifies, delivering to comparator circuit compares with zero level, obtain difference DIFF signal, be input to the ECL high-speed counting circuit, with the starting of two negative edges control high precision ECL counters of DIFF signal with stop, through the flight time digital signal after the processing of ECL high-speed counting circuit, deliver to high speed programmable circuit;

Simultaneously original scattering peak signal keeps the peak level of scattering peak signal through high-performance amplification, absolute value detecting circuit, converts the digital signal of scattered light intensity again to through the high-speed parallel A/D change-over circuit of high speed programmable circuit control; With two extensive programmable chips of high speed is data slice (21), the high speed programmable circuit that address slice (22) is formed, the mode record at aerosol particle spectrum/mass spectral flight time T_BUS and scattered light intensity SS_BUS and particle scattering peak is gone in the dual port memories chip, data slice (21) is mainly as the identification of particle signal and the buffer register of data, address slice (22) mainly is converted to the corresponding memory addresses spatial data with flight time and scattered light intensity digital data, and the read-write of dual port memories control, the identification particulate scattering peak pattern information that data slice 21 is correct, and allow address slice (22) latch flight time and scattered light intensity, obtain the proper memory address information, data slice (21) is read the content of this internal storage location in the data slice 16Bit register and is gone, and the content after will handling is deposited go back to the raw address space, preservation aerosol particle spectrum/mass spectral flight time and scattered light intensity information.

2, aerosol particle spectrum/mass spectrum flight time detection method as claimed in claim 1, it is characterized in that: the low-end cut-off frequency that is used for bandpass filter (4) that auto-correlation and signal are handled is arranged on 1KHz, high-end cutoff frequency is arranged on 500KHz, the low-end cut-off frequency that is used for bandpass filter (11) that the auto-correlation difference signal is handled is arranged on 1KHz, and high-end cutoff frequency is arranged on 3.16MHz.

3, aerosol particle spectrum mass spectrum/flight time pick-up unit, it is characterized in that the scattered light peak signal that is obtained by detector is input to stepping time delay module circuit, it is the analog addition circuit that core is formed that one group two road signal wires connect with OP467 (U1A), the analog addition circuit, with OP467 (U1C) is the active filter circuit of core, CLC501 (U2, U3) and the high speed clamping circuit formed of TLE2081 (U6), high speed comparator circuit HM96687 (U7A) connects successively, and set level Gate_Set for high speed comparator circuit HM96687 (U7A) provides thresholding, high speed comparator circuit HM96687 output ECL level and signal (GATE and/GATE);

Other one group of two road signal wire, series connection is the analog subtraction circuit that core is formed with OP467 (U1B), the analog subtraction circuit connect successively again filtering circuit filtering that the capacitance-resistance inductance forms, be high speed amplifying circuit, the high speed comparator circuit HM96687 (U7B) of core with CLC501 (U4), and for high speed comparator circuit HM96687 provides level "0" relatively, obtain the ECL level differential signal (DIFF and/DIFF);

The ECL level and signal (GATE and/GATE) and difference signal (DIFF and/DIFF) output line meets ECL-TTL level shifting circuit 10H125 (U16), the output Transistor-Transistor Logic level and signal (GATE_T) and zero cross signal (ZC), the GATE_T signal is connected the high speed processing circuit of high speed field programmable gate function MACH435 (U8, U9) composition with the ZC signal wire;

The ECL level and signal (GATE, / GATE) and difference signal (DIFF, / DIFF) the double D trigger 10H131 (U17) of output line connection ECL level is the logical circuit of core, connect again 20 that 8 digit counter 10H137 (U20) and Transistor-Transistor Logic level 12 digit counter 74HC4040 (U24) combine high-speed, the flight time counting circuit of big counting region, with frequency generator TQ2061 (U19) and 25MHz crystal oscillator (U25) is the High Speed ECL level clock generating circuit of core, the ECL clock signal up to 500MHz that produces can provide the temporal resolution up to 2ns, this clock is supplied with aforementioned flight time counting circuit, and the flight time counting circuit is connected with the high speed processing circuit;

Detector peak signal output line connects by OPA665 (U11, U12) and low pressure reduction and recovers high precision, the high-speed absolute value detecting circuit that schottky diode MMBD301 (CR301, CR302) related elements is formed soon, connecting with high-speed parallel A/D conversion chip again is core, be aided with the A/D change-over circuit that low noise high speed amplifier LM358 (U8B, U14A, U14B) and low noise high speed amplifier TLE2074 (U13A, U13B) form, the A/D change-over circuit is connected with the high speed processing circuit;

High speed processing circuit so that two extensive programmable chip MACH435 of high speed (U8, U9) form connects two-port RAM chip CY7C028 (U10).

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