A Method for Multi-parameter Robust Stability Distribution Analysis of Analog Circuits

Abstract

The invention belongs to the field of circuit analysis and relates to a method for analyzing distribution of robust stability of multiple parameters of an analog circuit. The method for analyzing distribution of robust stability of the complete analog circuit in multi-parameter space is combined with an analog circuit symbol emulation technique, stability judgment methods such as Routh Table in control theories, an interval calculation method, a high dimension segmentation technique and an importance sampling monte carlo method. According to the method, defects of prior art are overcome, a stability conclusion obtained by using the interval calculation method is a definitive conclusion; by means of a parameter axis correlation preferential segmentation technique, segmentation efficiency of high-dimensional parameter space is effectively improved; and stability percentage of a circuit parameter vector collection of which stability can not be judged is estimated by using the importance sampling monte carlo method based on volumes. The method is capable of solving the problem of stability of the analog circuit in the parameter space and the statistical problem of the stability percentage.

Description

technical field

[0001] The invention belongs to the field of circuit analysis methods, in particular to a method for analyzing multi-parameter robust stability distribution of analog circuits. Background technique

[0002] In the integrated circuit manufacturing process disclosed in the prior art, the relative error between the geometric and electrical parameters of the device obtained by tape-out and the design nominal value is not large, but as the integrated circuit semiconductor manufacturing technology moves to 65nm / 45nm / 32nm process With the development of nodes, complex processes such as sub-wavelength lithography under nanotechnology, Damascus copper interconnection and chemical mechanical polishing (CMP) are widely used, which makes the deviation between the actual silicon wafer pattern and the design layout increasingly serious[1, 2]. The interference and diffraction effects of light waves in the photolithography process cause severe distortion of the layout on th...

Examples

Embodiment 1

[0146] Through this embodiment, the stability percentage obtained by the method of the present invention is compared with the results of the random segmentation method and the Monte Carlo method.

[0147] The analog circuit uses a reversed active feedback frequency compensation (RAFFC) three-stage operational transconductance amplifier (three-stage operational transconductance amplifier) ​​[4] (circuit diagram as Figure 4 shown). Since the circuit parameters satisfy g m2 =g m3 =g mf ,r 0 = r 01 r 02 r 03 , where g m2 , g m3 , g mf is the transconductance, r 01 ,r 02 ,r 03 It is a resistor, and the number of circuit parameters can be reduced from 11 to 7. The nominal values ​​of the circuit parameters are:

[0148] g m1 =140uA / V,g mb =340uA / V,g mf =390uA / V

[0149] C C1 =11pF,C C2 =0.35pF,C L =500pF

[0150] r 0 =[10 15 ,10 20 ]

[0151] Among them, g m1 , g mb , g mf ,C C1 ,C C2 ,C L A disturbance of ±20% is given around the nominal value. The...

Embodiment 2

[0170] Example 2 gives the calculation result of a high-order biquadratic band pass filter (Biquadratic Band Pass Filter), the circuit diagram is as follows Figure 5 Shown in [21]. where the ideal voltage amplifier satisfies A 1 =A 2 =A 3 , and the reverse transmission coefficient satisfies μ=1 / A(s), A(s)=μ 0 +s / ω u , μ 0 =1 / A 0 , ω u =A 0 ω 1 . Use R=R 1 , R 3 = R 4 relationship, the number of circuit parameters can be reduced from 7 to 5. The nominal values ​​of its circuit parameters are:

[0171] R=10 3 Ω,R 2 =1.9e4Ω,R 3 =10 4 Ω,C=1.6e3pF,ω u =30.16Mhz

[0172] And give ±15% disturbance near the nominal value. The percent stability of this circuit needs to be estimated.

[0173] By the steps of the inventive method:

[0174] Step 1: Calculate the transfer function of the circuit using symbolic simulation tools.

[0175] Using the SapWin symbolic simulation tool, the transfer function of the circuit is calculated as:

[0176] H ...

technical field

[0001] The invention belongs to the field of circuit analysis methods, in particular to a method for analyzing multi-parameter robust stability distribution of analog circuits. Background technique

[0002] In the integrated circuit manufacturing process disclosed in the prior art, the relative error between the geometric and electrical parameters of the device obtained by tape-out and the design nominal value is not large, but as the integrated circuit semiconductor manufacturing technology moves to 65nm / 45nm / 32nm process With the development of nodes, complex processes such as sub-wavelength lithography under nanotechnology, Damascus copper interconnection and chemical mechanical polishing (CMP) are widely used, which makes the deviation between the actual silicon wafer pattern and the design layout increasingly serious[1, 2]. The interference and diffraction effects of light waves in the photolithography process cause severe distortion of the layout on th...

Examples

Embodiment 1

[0146] Through this embodiment, the stability percentage obtained by the method of the present invention is compared with the results of the random segmentation method and the Monte Carlo method.

[0147] The analog circuit uses a reversed active feedback frequency compensation (RAFFC) three-stage operational transconductance amplifier (three-stage operational transconductance amplifier) ​​[4] (circuit diagram as Figure 4 shown). Since the circuit parameters satisfy g m2 =g m3 =g mf ,r 0 = r 01 r 02 r 03 , where g m2 , g m3 , g mf is the transconductance, r 01 ,r 02 ,r 03 It is a resistor, and the number of circuit parameters can be reduced from 11 to 7. The nominal values ​​of the circuit parameters are:

[0148] g m1 =140uA / V,g mb =340uA / V,g mf =390uA / V

[0149] C C1 =11pF,C C2 =0.35pF,C L =500pF

[0150] r 0 =[10 15 ,10 20 ]

[0151] Among them, g m1 , g mb , g mf ,C C1 ,C C2 ,C L A disturbance of ±20% is given around the nominal value. The...

Embodiment 2

[0170] Example 2 gives the calculation result of a high-order biquadratic band pass filter (Biquadratic Band Pass Filter), the circuit diagram is as follows Figure 5 Shown in [21]. where the ideal voltage amplifier satisfies A 1 =A 2 =A 3 , and the reverse transmission coefficient satisfies μ=1 / A(s), A(s)=μ 0 +s / ω u , μ 0 =1 / A 0 , ω u =A 0 ω 1 . Use R=R 1 , R 3 = R 4 relationship, the number of circuit parameters can be reduced from 7 to 5. The nominal values ​​of its circuit parameters are:

[0171] R=10 3 Ω,R 2 =1.9e4Ω,R 3 =10 4 Ω,C=1.6e3pF,ω u =30.16Mhz

[0172] And give ±15% disturbance near the nominal value. The percent stability of this circuit needs to be estimated.

[0173] By the steps of the inventive method:

[0174] Step 1: Calculate the transfer function of the circuit using symbolic simulation tools.

[0175] Using the SapWin symbolic simulation tool, the transfer function of the circuit is calculated as:

[0176] H ...

Images