CN110958021A - High-speed high-precision current rudder digital-to-analog converter self-calibration system and method - Google Patents

High-speed high-precision current rudder digital-to-analog converter self-calibration system and method Download PDF

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CN110958021A
CN110958021A CN201911368913.8A CN201911368913A CN110958021A CN 110958021 A CN110958021 A CN 110958021A CN 201911368913 A CN201911368913 A CN 201911368913A CN 110958021 A CN110958021 A CN 110958021A
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calibration
current
current source
calibrated
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CN110958021B (en
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侯贺刚
张雷
张铁良
彭新芒
王金豪
任艳
管海涛
韩东群
孙丹
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Beijing Microelectronic Technology Institute
Mxtronics Corp
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Mxtronics Corp
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    • HELECTRICITY
    • H03ELECTRONIC CIRCUITRY
    • H03MCODING; DECODING; CODE CONVERSION IN GENERAL
    • H03M1/00Analogue/digital conversion; Digital/analogue conversion
    • H03M1/10Calibration or testing
    • H03M1/1009Calibration
    • H03M1/1028Calibration at two points of the transfer characteristic, i.e. by adjusting two reference values, e.g. offset and gain error

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Abstract

A high-speed high-precision current steering digital-to-analog converter self-calibration system and a method belong to the technical field of digital-to-analog converters. The invention comprises the following steps: the reference current source is connected to the positive input end of the current comparator, and the current source to be calibrated and the DAC module are connected to the negative input end of the current comparator for current comparison; the initial value of the calibration code is all 0, firstly, the highest bit of the calibration code is changed into 1, and whether the current calibration bit is 1 or not is determined according to the output result of the comparator; if the output result of the current comparator is high level 1, the current calibration bit is 1, otherwise, the current calibration bit is 0; then repeating the above processes from the second highest position to the lowest position in sequence until the K-bit calibration codes are all determined, and stopping comparison; latching the current calibration code in an error latch; the calibration DAC module generates calibration error compensation current under the control of the calibration code, and the current source calibration is completed; and the size of the total current obtained by adding the calibration error compensation current and the current of the current source to be calibrated is consistent with that of the current of the reference current source.

Description

High-speed high-precision current rudder digital-to-analog converter self-calibration system and method
Technical Field
The invention relates to a high-speed high-precision current steering digital-to-analog converter self-calibration method, and belongs to the technical field of digital-to-analog converters.
Background
The high-speed high-precision digital-to-analog converter is an important component of modern broadband communication, radar and other equipment, and the current-steering digital-to-analog converter is widely applied to a high-speed high-precision system due to the fact that the current-steering digital-to-analog converter has high working speed and can directly drive a resistive load. For a long time, due to the matching error limitation of the CMOS process, the current steering digital-to-analog converter realized only by intrinsic matching of the CMOS process can only achieve the precision of 10-12 bits generally. The static performance of the current steering digital-to-analog converter is mainly determined by the matching between current source tubes, the matching of a current source can be generally improved by increasing the sizes of the current source tubes, but the method is difficult to realize along with the improvement of the resolution of the digital-to-analog converter, because the resolution of the digital-to-analog converter is improved by 1 bit, the area of the current source tubes is increased in a geometric mode to meet the matching requirement, and the larger the area is, the higher the cost of a chip is.
With the increase of the conversion rate of the analog-to-digital converter, the dynamic performance of the current steering digital-to-analog converter is reduced along with the increase of the signal frequency and the clock frequency, and the dynamic performance of the current steering digital-to-analog converter can be improved by reducing the parasitic capacitance and resistance of the transistor and shortening the establishment time; however, to ensure the static performance of the current-steering dac, reducing the random mismatch and the system mismatch requires increasing the size of the transistor and the complex layout, which increases the parasitic capacitance and resistance of the transistor, which is in contrast to improving the dynamic performance of the current-steering dac.
In order to better solve the contradiction between the static performance and the dynamic performance improvement of the current steering analog-to-digital converter, a current source calibration technology is generally adopted, the requirement of matching on the area of a current source is reduced, and the improvement of the dynamic performance is not influenced; the current source calibration technology can effectively calibrate the current mismatch among all current sources, and ensures that the current steering analog-to-digital converter has high precision and high dynamic performance.
The digital-to-analog converter calibration technology can be divided into analog calibration and digital calibration according to the processing mode of a calibration control signal, and can be divided into foreground static calibration and background dynamic calibration according to whether a converter circuit works normally during calibration. The method is realized by continuous comparison and feedback in an analog domain, capacitor charging and discharging is generally adopted to maintain the grid source voltage of the current source tube, but the bias voltage of the current source tube needs to be continuously refreshed and adjusted due to the leakage phenomenon of the capacitor, and the calibration precision is not high. The digital background calibration technology can carry out calibration operation while a converter circuit works, and has the defects that a certain current source to be calibrated must be continuously replaced by a substitute current source, and the dynamic performance of a digital-to-analog converter is reduced due to the fact that switching current burrs are introduced when the substitute current source and the current source to be calibrated are continuously switched.
Disclosure of Invention
The invention aims to overcome the defects in the prior art and provides a high-speed high-precision self-calibration method for a current steering digital-to-analog converter. The self-calibration process does not need human interference, is in a completely automatic mode, can be completed by only once calibration, solves the problems of inaccurate analog calibration and repeated refreshing, solves the problem of reduced dynamic performance caused by digital background calibration, improves the calibration precision and the circuit performance, and can expand the calibration range and precision by adjusting the full-scale output current and the minimum weight current of the calibration DAC.
The technical solution of the invention is as follows: a high-speed high-precision current steering digital-to-analog converter self-calibration system comprises a reference current source, a current source to be calibrated, a current comparator, a calibration control logic module, an error latch and a calibration DAC module;
the reference current source provides reference current for comparison, and the output end of the reference current source is connected with the positive input end of the current comparator;
the output end of the current source to be calibrated is connected with the negative input end of the current comparator;
the current comparator is used for comparing the magnitude of the current input by the positive input end and the negative input end and outputting a comparison result to the input end of the calibration control logic module from the output end of the comparator;
the calibration control logic module is used for generating a calibration control signal by utilizing an internal state machine under the driving of the received calibration clock; the calibration control signal comprises a reference current source gating signal for controlling the on-off of a reference current source, a comparator enabling signal for controlling the on-off of a comparator, a current source gating signal to be calibrated for controlling the on-off of a current source to be calibrated, a calibration DAC module gating signal for controlling the on-off of a calibration DAC module and a calibration code for controlling the output current of the calibration DAC module;
the input end of the error latch is connected with the output end of the calibration control logic module, and the output end of the error latch is connected with the input end of the calibration DAC module, and is used for receiving and storing the calibration code and sending the calibration code to the calibration DAC module;
and the output end of the calibration DAC module is connected with the current comparator and is used for receiving the calibration code, generating comparison error current according to the calibration code and compensating the comparison error current to the current source to be calibrated.
Further, the reference current source includes a middle bit reference current source and a high bit reference current source, and the current comparator includes a middle bit comparator and a high bit comparator; the input ends of the middle-position reference current source and the high-position reference current source are connected with the output end of the calibration control logic module, and the output ends of the middle-position reference current source and the high-position reference current source are respectively connected with the positive input ends of the middle-position comparator and the high-position comparator; and the middle-position reference current source and the high-position reference current source respectively receive corresponding reference current source gating signals.
Further, the current source to be calibrated comprises a middle current source to be calibrated and a high current source to be calibrated; the input ends of the middle current source to be calibrated and the high current source to be calibrated are both connected with the output end of the calibration control logic module, the output end of the middle current source to be calibrated is connected with the negative input ends of the middle comparator and the high comparator, and the output end of the high current source to be calibrated is connected with the negative input end of the high comparator; and the middle current source to be calibrated and the high current source to be calibrated respectively receive corresponding gating signals of the current source to be calibrated.
Further, the calibration DAC module comprises a reference calibration DAC module for compensating the reference current source, and a middle position calibration DAC module and a high position calibration DAC module for compensating the middle position current source to be calibrated and the high position current source to be calibrated respectively; the input ends of the reference calibration DAC module, the middle calibration DAC module and the high calibration DAC module are connected with respective error latches; the output end of the reference calibration DAC module is connected with the positive input end of the middle-level comparator and the positive input end of the high-level comparator, the output ends of the middle-level calibration DAC module and the high-level calibration DAC module are respectively connected with the negative input ends of the middle-level comparator and the high-level comparator, and the calibration DAC module gating signals and the calibration codes are respectively received.
Further, a high-speed high-precision current steering digital-to-analog converter self-calibration method comprises the following steps:
and S1, carrying out middle current source calibration: the calibration control logic module sends enable ENP1 and enable SW1 signals, the enable ENP1 signal gates a median reference current source, the enable SW1 signal gates a matched calibration DAC module, and the current of the current median reference current source is I1<0>Current I1<0>The current weight is the same as that of the current source to be calibrated in the middle position; meanwhile, the calibration control logic module is used for referencing a median current sourceSetting the initial value of the calibration code of the matched calibration DAC module as INT<K:i>10 … 00, outputting the initial value compensation current IINTCurrent I1 of the current median reference current source<0>And the calibration initial value compensation current IINTGenerating a median reference current I1 by summing<0>+IINTThe current is used as a target for calibrating the self current of other middle current sources to be calibrated; i is a serial number;
s2, after the middle reference current setting is finished, the calibration control logic module sends enable S11<1>Signal gating a middle standby current source, transmit enable S33<1>The signal gates the matched middle position calibration DAC module, and simultaneously sends an enable SW3 signal to connect the middle position current source to be calibrated and the matched middle position calibration DAC module thereof to the negative input end of the middle position current comparator, and the middle position reference current I1<0>+IINTComparing the currents to generate a middle calibration code CAL1<K:i>(ii) a Calibrating the middle position code CAL1<K:i>Latching in a matched error latch, and forwarding to a corresponding middle position calibration DAC module, and controlling the middle position calibration DAC module to output a middle position calibration error compensation current I1A<1>(ii) a Output current I1 of median current source to be calibrated<1>Middle position calibration error compensation current I output by middle position calibration DAC module matched with middle position calibration current I1A<1>Generating an output current I1 by summing<1>+I1A<1>Completing the calibration of a middle-position current source to be calibrated;
s3, repeating S2 to finish the calibration of all the current sources to be calibrated in the middle position;
and S4, carrying out high-order current source calibration: calibration control logic module outputs enable S11 at the same time<M:1>Signal gating all the middle to-be-calibrated current sources, and enabling S33<M:1>Signal gating all the calibration DAC modules matched with the middle position current sources to be calibrated, and outputting an enabling SW4 signal to enable the output current I of all the calibrated middle position current sources1A<1>+I1<1>+I1A<2>+I1<2>+…+I1A<M>+I1<M>The negative input end of the high-order current comparator is accessed through addition; at the same time, the calibration control logic module sends an ENP2 enable signal and an SW2 enable signal, the ENP2 enable signal gates the high reference currentThe source, the enable SW2 signal gates the matched calibration DAC module thereof to be connected to the positive input end of the high-order current comparator for comparison, and the generated high-order reference compensation current is ISOutput current I2 of high-order reference current source<0>High-order reference compensation current I output by DAC module matched with the high-order reference compensation current ISGenerating a high level reference current I2 by summing<0>+ISThe current is used as a target for calibrating the self current of other high-order current sources to be calibrated;
s5, after the high-level reference current setting is completed, the calibration control logic module sends enable S22<1>The signal gates a high-order current source to be calibrated and sends an enable S44<1>The signal gates the matched calibration DAC module, and simultaneously sends an enable SW5 signal to connect the high-order current source to be calibrated and the matched calibration DAC module thereof into the negative input end of the high-order comparator, and the high-order current source to be calibrated and the matched calibration DAC module thereof are compared with the high-order reference current to generate a high-order calibration code CAL2<K:i>(ii) a Calibrating the high-order calibration code CAL2<K:i>Latched in a matched error latch, and forwarded to the corresponding high-order calibration DAC module to control the high-order calibration DAC module to output high-order calibration error compensation current I2A<1>(ii) a Output current I2 of high-order current source to be calibrated<1>High-order calibration error compensation current I output by DAC module matched with the high-order calibration error compensation current I2A<1>Generating an output current I2 by summing<1>+I2A<1>Completing the calibration of a high-order current source to be calibrated;
and S6, repeating S5, and completing the calibration of all the high-order current sources to be calibrated.
Further, the method for comparing the current with the reference current of the middle position or the high position comprises the following steps: a successive approximation method.
Compared with the prior art, the invention has the beneficial effects that:
(1) the digital self-calibration method of the high-speed high-precision current steering digital-to-analog converter is different from a permanent fixed and irreversible manual fuse trimming calibration mode, can automatically complete calibration according to different application environments, and has the advantages of simple and flexible calibration process and strong environmental adaptability.
(2) Compared with the analog calibration mode of correcting the grid source bias voltage of the current source tube, the digital self-calibration method of the high-speed high-precision current rudder digital-to-analog converter has high calibration precision, and can be completed by one-time calibration without repeated refreshing calibration.
(3) According to the digital self-calibration method of the high-speed high-precision current steering digital-to-analog converter, each current source to be calibrated is matched with one calibration DAC module and one error latch, and compared with a calibration mode with only one calibration DAC module, the digital self-calibration method of the high-speed high-precision current steering digital-to-analog converter is simple in calibration error information storage address decoding, small in digital logic scale and high in calibration speed.
(4) The digital self-calibration method of the high-speed high-precision current steering digital-to-analog converter can expand the precision and range of calibration by changing the digit of the calibration DAC module and the full-scale output current.
Drawings
FIG. 1 is a schematic diagram of the operation of the digital self-calibration system of the present invention;
FIG. 2 is a schematic diagram of a digital self-calibration system circuit configuration according to the present invention;
FIG. 3 is a schematic diagram of a high-level reference current source and a current source array to be calibrated according to the present invention;
FIG. 4 is a schematic diagram of the structure of the DAC calibration module according to the present invention, which is exemplified by a 6-bit 2+4 segmented structure.
Detailed Description
The present invention will be described in further detail with reference to the accompanying drawings and specific examples.
A modern high-speed high-precision digital-to-analog converter usually adopts an A + B + C segmented current rudder structure, wherein a high-A bit and a middle-B bit are decoded by thermometers and respectively control a unit current source, and a low-C bit is decoded by a binary system and controls a binary system weighted current source; thermometer coded high A bit to 2A-1 bit, control 2A-1 current weight of (2)B+C)I0The middle B bit thermometer coded to 2B-1 bit, control 2B-1 current weight of (2)C)I0The low C bit adopts binary decoding to control a binary weighted current source, and the total current weight is (2)C-1)I0The low C-bit current is split from a mid-bit current source by binary weighting, I0Is the most importantThe small weight current, called the digital to analog converter 1LSB current.
A high-speed high-precision current steering digital-to-analog converter self-calibration system comprises a reference current source, a current source to be calibrated, a current comparator, a calibration control logic module, an error latch and a calibration DAC module, and is respectively a working schematic diagram and a circuit structure schematic diagram of the digital self-calibration system as shown in figures 1 and 2.
The reference current source provides a reference current for comparison, all current sources to be calibrated are compared with, and the output end of the reference current source is connected with the positive input end of the current comparator. The reference current source comprises a middle bit reference current source and a high bit reference current source, and the current comparator comprises a middle bit comparator and a high bit comparator; the input ends of the middle-position reference current source and the high-position reference current source are connected with the output end of the calibration control logic module, and the output ends of the middle-position reference current source and the high-position reference current source are respectively connected with the positive input ends of the middle-position comparator and the high-position comparator; and the middle-position reference current source and the high-position reference current source respectively receive corresponding reference current source gating signals.
The current source to be calibrated is a current source to be calibrated, all middle-order current sources and high-order current sources of the current steering digital-to-analog converter in the self-calibration method need to be calibrated, and N is 2 in totalA-1 high-side current sources, M2BThe middle current source, as shown in fig. 3, is a schematic diagram of the structures of the middle and high reference current sources and the current source to be calibrated. The output end of the current comparator is connected with the negative input end of the current comparator. The current source to be calibrated comprises a middle current source to be calibrated and a high current source to be calibrated; the input ends of the middle current source to be calibrated and the high current source to be calibrated are both connected with the output end of the calibration control logic module, the output end of the middle current source to be calibrated is connected with the negative input ends of the middle comparator and the high comparator, and the output end of the high current source to be calibrated is connected with the negative input end of the high comparator; and the middle current source to be calibrated and the high current source to be calibrated respectively receive corresponding gating signals of the current source to be calibrated.
The current comparator is used for comparing the current input by the positive input end and the negative input end, and outputting a comparison result from the output end of the comparator to the input end of the calibration control logic module. The current comparator comprises a middle-position current comparator and a high-position current comparator; if the input current of the positive input end is larger than the input current of the negative input end, the current comparator outputs a high level 1, and if the input current of the positive input end is smaller than the input current of the negative input end, the current comparator outputs a low level 0.
The calibration control logic module is used for generating a calibration control signal by utilizing an internal state machine under the driving of the received calibration clock; the calibration control signal comprises a reference current source gating signal for controlling the on-off of a reference current source, a comparator enabling signal for controlling the on-off of a comparator, a current source gating signal to be calibrated for controlling the on-off of a current source to be calibrated, a calibration DAC module gating signal for controlling the on-off of a calibration DAC module and a calibration code for controlling the output current of the calibration DAC module. The calibration control signals comprise reference current source gating signals ENP1 and ENP2, a comparator enabling signal ENP3, current source gating signals S11< M:1>, S22< N:1>, calibration DAC gating signals S33< M:1>, S44< N:1>, SW1, SW2, SW3, SW4 and SW5 to be calibrated, calibration codes CAL < K:1> and INT < K:1 >.
The input end of the error latch is connected with the output end of the calibration control logic module, and the output end of the error latch is connected with the input end of the calibration DAC module, and the error latch is used for receiving and storing the calibration code and sending the calibration code to the calibration DAC module. The error latch is a K-bit register and can be implemented by simple latch, and each calibration DAC is matched with an error latch.
And the output end of the calibration DAC is connected with the current comparator and is used for receiving the calibration code, generating a comparison error current according to the calibration code and compensating the comparison error current to the current source to be calibrated. The calibration DAC module comprises a reference calibration DAC module for compensating a reference current source, and a middle position calibration DAC module and a high position calibration DAC module which are respectively used for compensating a middle position current source to be calibrated and a high position current source to be calibrated; the input ends of the reference calibration DAC module, the middle calibration DAC module and the high calibration DAC module are connected with respective error latches; the output end of the reference calibration DAC module is connected with the positive input ends of the middle-level comparator and the high-level comparator, and the middle-level calibration DAC moduleAnd the output end of the high-order calibration DAC module is respectively connected with the negative input ends of the middle-order comparator and the high-order comparator, and respectively receives the gating signal and the calibration code of the calibration DAC module. Each reference current source and the current source to be calibrated are matched with a calibration DAC. The calibration DAC is structurally a K-bit current steering DAC, and a calibration code CAL<K:1>Determining the output current of the DAC, and calibrating the DAC to adopt an i + j segmented current steering structure, wherein i + j is equal to K; in general, to ensure the accuracy of the calibration, the minimum weight current of the calibration DAC is less than 1/3 of the minimum weight current of the main DAC, and in this method, the minimum weight current of the calibration DAC is set to 1/4, i.e. I, of the minimum weight current of the main DAC1=I0/4. Fig. 4 is a schematic diagram of a structure of a calibration DAC module according to the present invention, which takes a 6-bit 2+4 segmented current steering structure as an example.
The self-calibration method of the high-speed high-precision current steering digital-to-analog converter adopts a one-way calibration mode, namely, the current of a current source to be calibrated is set to be smaller than the current of a reference current source, the current of the current source to be calibrated is compensated by a calibration DAC, the current value of the current source to be calibrated approaches the current value of the reference current source by adopting a successive approximation comparison mode until the current value is approximately equal, and the calibration is finished; the current of the reference current source is the target of DAC current source calibration, and when the DAC current source is designed, the current of the reference current source is set to be larger than the current of the current source to be calibrated, and the set value is usually half of the total output current of the DAC to be calibrated. The self-calibration specific implementation method of the high-speed high-precision current steering digital-to-analog converter is as follows:
and S1, carrying out middle current source calibration: the calibration control logic module sends enable ENP1 and enable SW1 signals, the enable ENP1 signal gates a median reference current source, the enable SW1 signal gates a matched calibration DAC module, and the current of the current median reference current source is I1<0>Current I1<0>The current weight is the same as that of the current source to be calibrated in the middle position; meanwhile, the calibration control logic module sets the initial value of the calibration code of the calibration DAC module matched with the middle-position reference current source to INT<K:i>10 … 00, outputting the initial value compensation current IINTCurrent I1 of the current median reference current source<0>And the calibration initial value compensation current IINTGenerating a median reference by summingCurrent I1<0>+IINTThe current is used as a target for calibrating the self current of other middle current sources to be calibrated;
s2, after the middle reference current setting is finished, the calibration control logic module sends enable S11<1>Signal gating a middle standby current source, transmit enable S33<1>The signal gates the matched middle position calibration DAC module, and simultaneously sends an enable SW3 signal to connect the middle position current source to be calibrated and the matched middle position calibration DAC module thereof into the negative input end of the middle position current comparator, and the negative input end of the middle position reference current I1<0>+IINTComparing the currents to generate a middle calibration code CAL1<K:i>(ii) a Calibrating the middle position code CAL1<K:i>Latching in a matched error latch, and forwarding to a corresponding middle position calibration DAC module, and controlling the middle position calibration DAC module to output a middle position calibration error compensation current I1A<1>(ii) a Output current I1 of median current source to be calibrated<1>Middle position calibration error compensation current I output by middle position calibration DAC module matched with middle position calibration current I1A<1>Generating an output current I1 by summing<1>+I1A<1>Completing the calibration of a middle-position current source to be calibrated;
s3, repeating S2 to finish the calibration of all the current sources to be calibrated in the middle position;
and S4, carrying out high-order current source calibration: calibration control logic module outputs enable S11 at the same time<M:1>Signal gating all the middle to-be-calibrated current sources, and enabling S33<M:1>Signal gating all the calibration DAC modules matched with the middle position current sources to be calibrated, and outputting an enabling SW4 signal to enable the output current I of all the calibrated middle position current sources1A<1>+I1<1>+I1A<2>+I1<2>+…+I1A<M>+I1<M>The negative input end of the high-order current comparator is accessed through addition; meanwhile, the calibration control logic module sends an enable ENP2 signal and an enable SW2 signal, the enable ENP2 signal gates the high-order reference current source, the enable SW2 signal gates a matched calibration DAC module thereof to be connected to the positive input end of the high-order current comparator for comparison, and the generated high-order reference compensation current is ISOutput current I2 of high-order reference current source<0>High-order reference matched with high-order reference for calibrating DAC module outputCompensating current ISGenerating a high level reference current I2 by summing<0>+ISFinishing the setting of the high-level reference current;
s5, after the high-level reference current setting is completed, the calibration control logic module sends enable S22<1>The signal gates a high-order current source to be calibrated and sends an enable S44<1>The signal gates the matched calibration DAC module, and simultaneously sends an enable SW5 signal to connect the high-order current source to be calibrated and the matched calibration DAC module thereof into the negative input end of the high-order comparator, and the high-order current source to be calibrated and the matched calibration DAC module thereof are compared with the high-order reference current to generate a high-order calibration code CAL2<K:i>(ii) a Calibrating the high-order calibration code CAL2<K:i>Latched in a matched error latch, and forwarded to the corresponding high-order calibration DAC module to control the high-order calibration DAC module to output high-order calibration error compensation current I2A<1>(ii) a Output current I2 of high-order current source to be calibrated<1>High-order calibration error compensation current I output by DAC module matched with the high-order calibration error compensation current I2A<1>Generating an output current I2 by summing<1>+I2A<1>Completing the calibration of a high-order current source to be calibrated;
and S6, repeating S5, and completing the calibration of all the high-order current sources to be calibrated.
A high-speed high-precision current steering digital-to-analog converter self-calibration method is characterized in that a successive approximation method is adopted for current comparison, and a calibration code changes from a high bit to a low bit one by one, so that the output current of a calibration DAC is changed; the initial value of the calibration code is all 0, the highest bit of the calibration code is changed into 1 when the calibration is started, whether the current calibration bit is 1 or not is determined according to the output result of the current comparator, if the output result of the current comparator is high level 1, the current calibration bit is 1, and if not, the current calibration bit is 0; and repeating the processes from the second highest bit to the lowest bit in sequence until the K-bit calibration codes are all determined, and stopping comparison.
The above description is only for the best mode of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are included in the scope of the present invention.
Those skilled in the art will appreciate that those matters not described in detail in the present specification are well known in the art.

Claims (6)

1.一种高速高精度电流舵数模转换器自校准系统,其特征在于:包括参考电流源、待校准电流源、电流比较器、校准控制逻辑模块、误差锁存器、校准DAC模块;1. A high-speed high-precision current rudder digital-to-analog converter self-calibration system, characterized in that: comprising a reference current source, a current source to be calibrated, a current comparator, a calibration control logic module, an error latch, and a calibration DAC module; 参考电流源,提供用于比较的基准电流,其输出端连接电流比较器正输入端;The reference current source provides the reference current for comparison, and its output terminal is connected to the positive input terminal of the current comparator; 待校准电流源,其输出端连接电流比较器的负输入端;The current source to be calibrated, the output terminal of which is connected to the negative input terminal of the current comparator; 电流比较器,用于比较正输入端和负输入端输入的电流大小,并将比较结果从比较器输出端输出至校准控制逻辑模块的输入端;The current comparator is used to compare the magnitude of the current input by the positive input terminal and the negative input terminal, and output the comparison result from the comparator output terminal to the input terminal of the calibration control logic module; 校准控制逻辑模块,用于在接收的校准时钟的驱动下利用内部状态机生成校准控制信号;所述校准控制信号包括用于控制参考电流源通断的参考电流源选通信号、用于控制比较器通断的比较器使能信号、用于控制待校准电流源通断的待校准电流源选通信号、用于控制校准DAC模块通断的校准DAC模块选通信号和用于控制校准DAC模块输出电流大小的校准码;The calibration control logic module is used to generate a calibration control signal by using the internal state machine under the drive of the received calibration clock; the calibration control signal includes a reference current source gating signal used to control the on-off of the reference current source, a reference current source gating signal used to control the comparison Comparator enable signal for on-off, current source gating signal for controlling the on-off of the current source to be calibrated, calibration DAC module gating signal for controlling the on-off of the calibration DAC module, and gating signal for controlling the calibration DAC module The calibration code of the output current size; 误差锁存器,输入端与校准控制逻辑模块的输出端连接,输出端与校准DAC模块的输入端连接,用于接收和存储校准码,并发送至校准DAC模块;Error latch, the input end is connected with the output end of the calibration control logic module, and the output end is connected with the input end of the calibration DAC module, for receiving and storing the calibration code, and sending it to the calibration DAC module; 校准DAC模块,输出端连接电流比较器,用于接收校准码,并根据校准码生成比较误差电流,补偿至待校准电流源。The DAC module is calibrated, and the output end is connected to a current comparator, which is used to receive the calibration code, and generate a comparison error current according to the calibration code, which is compensated to the current source to be calibrated. 2.根据权利要求1所述的一种高速高精度电流舵数模转换器自校准系统,其特征在于:所述参考电流源包括中位参考电流源和高位参考电流源,所述电流比较器包括中位比较器和高位比较器;所述中位参考电流源和高位参考电流源的输入端均连接在校准控制逻辑模块的输出端,输出端分别连接中位比较器和高位比较器的正输入端;所述中位参考电流源和高位参考电流源分别接收对应的参考电流源选通信号。2 . The self-calibration system of a high-speed and high-precision current steering digital-to-analog converter according to claim 1 , wherein the reference current source comprises a mid-level reference current source and a high-level reference current source, and the current comparator Including a mid-level comparator and a high-level comparator; the input ends of the intermediate-level reference current source and the high-level reference current source are connected to the output end of the calibration control logic module, and the output ends are respectively connected to the positive-level comparator and the high-level comparator. an input end; the middle reference current source and the high reference current source respectively receive the corresponding reference current source gating signal. 3.根据权利要求2所述的一种高速高精度电流舵数模转换器自校准系统,其特征在于:所述待校准电流源包括中位待校准电流源和高位待校准电流源;所述中位待校准电流源和高位待校准电流源的输入端均连接校准控制逻辑模块的输出端,中位待校准电流源的输出端连接中位比较器和高位比较器的负输入端,高位待校准电流源的输出端连接高位比较器的负输入端;所述中位待校准电流源和高位待校准电流源分别接收对应的待校准电流源选通信号。3. A high-speed and high-precision current steering digital-to-analog converter self-calibration system according to claim 2, characterized in that: the current source to be calibrated comprises a neutral current source to be calibrated and a high current source to be calibrated; the The input terminals of the mid-level current source to be calibrated and the high-level current source to be calibrated are connected to the output terminal of the calibration control logic module, and the output terminal of the mid-level to-be-calibrated current source is connected to the negative input terminals of the mid-level comparator and the high-level comparator. The output end of the calibration current source is connected to the negative input end of the high-level comparator; the middle-level to-be-calibrated current source and the high-level to-be-calibrated current source respectively receive the corresponding to-be-calibrated current source gating signals. 4.根据权利要求2所述的一种高速高精度电流舵数模转换器自校准系统,其特征在于:所述校准DAC模块包括用于补偿参考电流源的参考校准DAC模块以及分别用于补偿中位待校准电流源和高位待校准电流源的中位校准DAC模块和高位校准DAC模块;所述参考校准DAC模块、中位校准DAC模块和高位校准DAC模块的输入端均连接各自的误差锁存器;所述参考校准DAC模块的输出端连接中位比较器和高位比较器的正输入端,所述中位校准DAC模块和高位校准DAC模块的输出端分别连接中位比较器和高位比较器的负输入端,分别接收的校准DAC模块选通信号和校准码。4. The self-calibration system of a high-speed and high-precision current steering digital-to-analog converter according to claim 2, wherein the calibration DAC module comprises a reference calibration DAC module for compensating the reference current source and a reference calibration DAC module for compensating The median calibration DAC module and the upper calibration DAC module of the median current source to be calibrated and the upper calibration current source; the input ends of the reference calibration DAC module, the median calibration DAC module and the upper calibration DAC module are connected to their respective error locks The output end of the reference calibration DAC module is connected to the positive input end of the median comparator and the upper comparator, and the output ends of the middle calibration DAC module and the upper calibration DAC module are respectively connected to the median comparator and the upper comparator The negative input terminal of the device receives the calibration DAC module strobe signal and calibration code respectively. 5.一种高速高精度电流舵数模转换器自校准方法,其特征在于,包括如下步骤:5. a high-speed high-precision current rudder digital-to-analog converter self-calibration method, is characterized in that, comprises the steps: S1,进行中位电流源校准:校准控制逻辑模块发送使能ENP1和使能SW1信号,所述使能ENP1信号选通中位参考电流源,所述使能SW1信号选通其配套校准DAC模块,当前中位参考电流源的电流为I1<0>,电流I1<0>与中位待校准电流源电流权重相同;同时,校准控制逻辑模块将中位参考电流源配套的校准DAC模块的校准码初值设置为INT<K:i>=10…00,输出校准初值补偿电流IINT,当前中位参考电流源的电流I1<0>与校准初值补偿电流IINT通过加和生成中位参考基准电流I1<0>+IINT,作为其它中位待校准电流源校准自身电流的标的;i为编号;S1, perform median current source calibration: the calibration control logic module sends the enable ENP1 and enable SW1 signals, the enable ENP1 signal gates the median reference current source, and the enable SW1 signal gates its matching calibration DAC module , the current of the current median reference current source is I1<0>, and the current I1<0> is the same as the current weight of the median current source to be calibrated; at the same time, the calibration control logic module calibrates the calibration DAC module matched with the median reference current source. The initial value of the code is set to INT<K:i>=10…00, the output calibration initial value compensation current I INT , the current I1<0> of the current median reference current source and the calibration initial value compensation current I INT are generated by adding Bit reference reference current I1<0>+I INT , as the target of other neutral current sources to be calibrated to calibrate their own current; i is the number; S2,完成中位参考基准电流设定后,校准控制逻辑模块发送使能S11<1>信号选通一个中位待校准电流源,发送使能S33<1>信号选通其配套中位校准DAC模块,同时发送使能SW3信号将中位待校准电流源及其配套中位校准DAC模块接入中位电流比较器负输入端,与所述中位参考基准电流I1<0>+IINT进行电流比较,生成中位校准码CAL1<K:i>;将中位校准码CAL1<K:i>锁存在配套的误差锁存器,并转发至对应中位校准DAC模块,控制中位校准DAC模块输出中位校准误差补偿电流I1A<1>;中位待校准电流源的输出电流I1<1>与其配套中位校准DAC模块输出的中位校准误差补偿电流I1A<1>通过加和生成输出电流I1<1>+I1A<1>,完成一个中位待校准电流源的校准;S2, after completing the setting of the median reference reference current, the calibration control logic module sends the enable S11<1> signal to select a median current source to be calibrated, and sends the enable S33<1> signal to select its matching median calibration DAC module, at the same time send the enable SW3 signal to connect the median current source to be calibrated and its matching median calibration DAC module to the negative input end of the median current comparator, and conduct the process with the median reference reference current I1<0>+ IINT Compare the current, generate the median calibration code CAL1<K:i>; latch the median calibration code CAL1<K:i> in the matching error latch, and forward it to the corresponding median calibration DAC module to control the median calibration DAC The module outputs the median calibration error compensation current I 1A <1>; the output current I1<1> of the median current source to be calibrated and the median calibration error compensation current I 1A <1> output by the matching median calibration DAC module are added by adding Generate output current I1<1>+I 1A <1>, complete the calibration of a neutral current source to be calibrated; S3,重复S2,完成所有中位待校准电流源的校准;S3, repeat S2 to complete the calibration of all median current sources to be calibrated; S4,进行高位电流源校准:校准控制逻辑模块同时输出使能S11<M:1>信号选通所有中位待校准电流源,以及使能S33<M:1>信号选通所有中位待校准电流源配套的校准DAC模块,并输出使能SW4信号将所有校准后的中位电流源的输出电流I1A<1>+I1<1>+I1A<2>+I1<2>+…+I1A<M>+I1<M>通过加和接入高位电流比较器负输入端;同时,校准控制逻辑模块发送使能ENP2信号和使能SW2信号,所述使能ENP2信号选通高位参考电流源,所述使能SW2信号选通其配套校准DAC模块接入高位电流比较器正输入端,进行比较,生成高位参考补偿电流为IS,高位参考电流源的输出电流I2<0>与其配套校准DAC模块输出的高位参考补偿电流IS通过加和生成高位参考基准电流I2<0>+IS,作为其它高位待校准电流源校准自身电流的标的;S4, perform high-level current source calibration: the calibration control logic module simultaneously outputs the enable S11<M:1> signal to select all the neutral current sources to be calibrated, and enables the S33<M:1> signal to select all the neutral current sources to be calibrated The calibration DAC module matched with the current source, and the output enable SW4 signal will output the output current of all the calibrated median current sources I 1A <1>+I1<1>+I 1A <2>+I1<2>+…+ I 1A <M>+I1<M> is connected to the negative input terminal of the high-bit current comparator through summation; at the same time, the calibration control logic module sends the enable ENP2 signal and the enable SW2 signal, and the enable ENP2 signal strobes the high-bit reference The current source, the enable SW2 signal is gated and its matching calibration DAC module is connected to the positive input end of the high-level current comparator, and compared to generate a high-level reference compensation current I S , and the output current I2<0> of the high-level reference current source is the same as that of the current source. The high-level reference compensation current I S output by the matching calibration DAC module generates a high-level reference reference current I2<0>+I S by summation, which is used as the target for other high-level current sources to be calibrated to calibrate their own currents; S5,完成高位参考基准电流设定后,校准控制逻辑模块发送使能S22<1>信号选通一个高位待校准电流源,并发送使能S44<1>信号选通其配套校准DAC模块,同时发送使能SW5信号将高位待校准电流源和其配套校准DAC模块接入高位比较器负输入端,与高位参考基准电流进行电流比较,生成高位校准码CAL2<K:i>;将高位校准码CAL2<K:i>锁存在配套的误差锁存器,并转发至对应高位校准DAC模块,控制高位校准DAC模块输出高位校准误差补偿电流I2A<1>;高位待校准电流源的输出电流I2<1>与其配套校准DAC模块输出的高位校准误差补偿电流I2A<1>通过加和生成输出电流I2<1>+I2A<1>,完成一个高位待校准电流源的校准;S5, after completing the high-level reference reference current setting, the calibration control logic module sends the enable S22<1> signal to select a high-level current source to be calibrated, and sends the enable S44<1> signal to select its matching calibration DAC module, and at the same time Send the enable SW5 signal to connect the high-level current source to be calibrated and its matching calibration DAC module to the negative input of the high-level comparator, compare the current with the high-level reference reference current, and generate the high-level calibration code CAL2<K:i>;CAL2<K:i> is latched in the matching error latch and forwarded to the corresponding high-level calibration DAC module to control the high-level calibration DAC module to output the high-level calibration error compensation current I 2A <1>; the output current I2 of the high-level current source to be calibrated <1> The high-level calibration error compensation current I 2A output by the DAC module is calibrated with it. <1> The output current I2<1>+I 2A <1> is generated by summation to complete the calibration of a high-level current source to be calibrated; S6,重复S5,完成所有高位待校准电流源的校准。S6, repeat S5 to complete the calibration of all high-level current sources to be calibrated. 6.根据权利要求5所述的一种高速高精度电流舵数模转换器自校准方法,其特征在于,与中位或高位参考基准电流进行电流比较的方法为:逐次逼近方法。6 . The self-calibration method for a high-speed and high-precision current steering digital-to-analog converter according to claim 5 , wherein the method for comparing the current with a mid-level or high-level reference reference current is a successive approximation method. 7 .
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Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112781743A (en) * 2021-01-12 2021-05-11 中国电子科技集团公司第五十八研究所 CMOS temperature sensor circuit applied to SoC and working method thereof
CN112799457A (en) * 2020-12-31 2021-05-14 深圳市紫光同创电子有限公司 Voltage calibration circuit and method
CN112886964A (en) * 2021-01-12 2021-06-01 中国电子科技集团公司第五十八研究所 Digital foreground calibration circuit and method applied to high-speed high-precision current steering DAC
CN113867463A (en) * 2021-10-08 2021-12-31 深圳市乾鸿微电子有限公司 One-time trimming and calibrating structure of current source
CN114019415A (en) * 2022-01-06 2022-02-08 宜矽源半导体南京有限公司 Integrated short-circuit current detector with variable threshold, self-calibration and high precision
CN114095021A (en) * 2021-11-24 2022-02-25 北京博瑞微电子科技有限公司 A method and circuit for calibrating resistance mismatch of a resistance digital-to-analog converter
CN114326900A (en) * 2021-12-29 2022-04-12 华中科技大学 A high-precision adjustable reference voltage generating circuit
CN114337664A (en) * 2022-03-09 2022-04-12 华南理工大学 A current rudder digital-to-analog converter with multi-level calibration
CN118054792A (en) * 2024-03-22 2024-05-17 深圳大学 Current rudder data conversion circuit and synthetic aperture radar single-bit system

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101777914A (en) * 2010-01-08 2010-07-14 西安电子科技大学 High-precision current-steering digital to analog converter and error calibrating method thereof
US20130027235A1 (en) * 2011-07-28 2013-01-31 Fujitsu Semiconductor Limited Self-Calibrated DAC with Reduced Glitch Mapping
CN103684457A (en) * 2013-12-13 2014-03-26 中国电子科技集团公司第五十八研究所 Method for calibrating power source array in segmented type current-steering DAC
CN104065382A (en) * 2013-03-22 2014-09-24 西安电子科技大学 Digital Calibration Technique for Segmented Current Steering DAC
CN106330184A (en) * 2016-08-22 2017-01-11 电子科技大学 A Current Steering DAC Based on Dynamic Error Correction Technology
CN107517058A (en) * 2017-08-25 2017-12-26 电子科技大学 A Segmented Current Steering DAC with Correction Function and Its Background Correction Method
CN108449089A (en) * 2018-03-23 2018-08-24 上海唯捷创芯电子技术有限公司 Realize current steering digital-to-analog converter, chip and the communication terminal of digital calibration

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101777914A (en) * 2010-01-08 2010-07-14 西安电子科技大学 High-precision current-steering digital to analog converter and error calibrating method thereof
US20130027235A1 (en) * 2011-07-28 2013-01-31 Fujitsu Semiconductor Limited Self-Calibrated DAC with Reduced Glitch Mapping
CN104065382A (en) * 2013-03-22 2014-09-24 西安电子科技大学 Digital Calibration Technique for Segmented Current Steering DAC
CN103684457A (en) * 2013-12-13 2014-03-26 中国电子科技集团公司第五十八研究所 Method for calibrating power source array in segmented type current-steering DAC
CN106330184A (en) * 2016-08-22 2017-01-11 电子科技大学 A Current Steering DAC Based on Dynamic Error Correction Technology
CN107517058A (en) * 2017-08-25 2017-12-26 电子科技大学 A Segmented Current Steering DAC with Correction Function and Its Background Correction Method
CN108449089A (en) * 2018-03-23 2018-08-24 上海唯捷创芯电子技术有限公司 Realize current steering digital-to-analog converter, chip and the communication terminal of digital calibration

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112799457A (en) * 2020-12-31 2021-05-14 深圳市紫光同创电子有限公司 Voltage calibration circuit and method
CN112781743A (en) * 2021-01-12 2021-05-11 中国电子科技集团公司第五十八研究所 CMOS temperature sensor circuit applied to SoC and working method thereof
CN112886964A (en) * 2021-01-12 2021-06-01 中国电子科技集团公司第五十八研究所 Digital foreground calibration circuit and method applied to high-speed high-precision current steering DAC
CN112781743B (en) * 2021-01-12 2021-11-02 中国电子科技集团公司第五十八研究所 CMOS temperature sensor circuit applied to SoC and working method thereof
CN112886964B (en) * 2021-01-12 2021-12-14 中国电子科技集团公司第五十八研究所 Digital foreground calibration circuit and method applied to high-speed high-precision current steering DAC
CN113867463A (en) * 2021-10-08 2021-12-31 深圳市乾鸿微电子有限公司 One-time trimming and calibrating structure of current source
CN114095021A (en) * 2021-11-24 2022-02-25 北京博瑞微电子科技有限公司 A method and circuit for calibrating resistance mismatch of a resistance digital-to-analog converter
CN114326900A (en) * 2021-12-29 2022-04-12 华中科技大学 A high-precision adjustable reference voltage generating circuit
CN114019415A (en) * 2022-01-06 2022-02-08 宜矽源半导体南京有限公司 Integrated short-circuit current detector with variable threshold, self-calibration and high precision
CN114337664A (en) * 2022-03-09 2022-04-12 华南理工大学 A current rudder digital-to-analog converter with multi-level calibration
CN114337664B (en) * 2022-03-09 2022-06-03 华南理工大学 A current rudder digital-to-analog converter with multi-level calibration
CN118054792A (en) * 2024-03-22 2024-05-17 深圳大学 Current rudder data conversion circuit and synthetic aperture radar single-bit system

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