TWI228011B - System of multi-channel shared resistor-string digital-to-analog converters and method of the same - Google Patents

Abstract

System of multi-channel shared resistor-string digital-to-analog converters comprises a time-sharing interpolator transforming the multi-channel digital audio input at low sample rate to the multi-channel digital audio output at high sample rate, a time-sharing sigma-delta modulator modulating the multi-channel digital audio input with a long sample wordlength from the interpolator to be a multi-channel digital audio output with a shorter sample wordlength, multi-channel shared resistor-string digital-to-analog converters converting the multi-channel digital audio input to be a multi-channel staircase analog signal output, and one low-order RC filter for each channel further attenuating the out-of-band noise in the analog staircase analog output, especially the high-frequency residue images.

Description

Case No. 92117347 1228011 Amendment V. Description of the invention (1) 1. Technical field to which the invention belongs: The present invention relates to a multi-channel audio channel audi) Number: 'Member: converter related', especially about a high-resolution multi-channel The channels share the ^ A, U1S1ta1-1o-analog converters (DACs) system and its output method. Second, the prior art:

In the audio (audi0) digital analog conversion (D / A conversion) field, the processing frequency is not high, but the accuracy requirements are even greater than in other fields. (Irr the technical field 〇f the audi〇 ♦ digital-to ^ analog conversion, the conversion rate i not high, but the accuracy requirement is getting more ar ^ d more stringent ·), and due to the current music application specifications, (The audio application specifications demand multi-channel playback much more than before), so how to 'maintain low-cost competitiveness while considering multi-channel output and demanding precision requirements has become a major problem. Among the accuracy specifications, dynamic range (DR) and signal-to-noise-plus-distortion ratio (SNDR) are the most important.

Page 8 1228011 Amendment Case No. 92117347 V. Description of the Invention (2) Measurement of noise generated by converters, measurement of linearity of two converters. Digital class | Sample frequency can be divided into two categories of Nyquist sample converters. One of the implementation methods is a resistor string | resistor string digital analog converter. The resistance matching of the electric embryo is limited by VLS ^ [technical mismatch, which directly affects the electric ‘string division | resistance string digital analog converter ’s signal’ traditionally has a high resolution life: bit class =. The dynamic range is logarithmic analog = noise ratio * distortion ratio can be regarded as many types of converters, depending on the yquist-rate) converter and the frequency multiplier. Among the Nyquist rate converters, the most straightforward Digital analog converters (DACs) or electrical, string digital analog converters' main disadvantage is the resistance voltage accuracy due to process deviation. The voltage division accuracy is insufficient, which makes the electrical to noise and distortion ratios perform poorly, and therefore the ratio is not high compared to that used in conversion. However, resistance string digital analog converters also have their advantages. One of them is that resistance string digital analog converters can provide high dynamic range. Because & resistance string digital | Analog converter noise sources mainly come from the thermal noise of the resistor string (thermal noise) of the switch and the output buffer amplifier (〇utpu1: buffer) and 1 / ί noise, noise The signal layer (noisef 100r) is extremely low. Therefore, it enjoys the dynamic range characteristic of polar bubbles. Another advantage of the digital string analog converter is that it can be operated at local speed, so it is good for high sampling rate conversion applications. Frequency-sampling digital analog converters are mainly integrating delta (sigma — delta: Σ | △) digital analog converters, and have occupied high-resolution tones for many years. Page 9

I 1228011 — _____ Case No. 92117347_ year month day ____ 5. Description of the invention (3), a large proportion in the frequency analog conversion market. Figure 1 shows a system block diagram of a typical single-channel integrating delta-digital analog converter. Its input is N-bit (N can be 16, 18, 20, 24) Nyquist-rate PCM digital sound source, and its sampling frequency FN_in is up to R times after being up-converted by the interpolator 100. That is, the sampling frequency becomes RFN_in, but the n-bit PCM output format is still maintained. The data of the N-bit RFN_in sampling rate is then reduced to M (red l / he wordlength to M-bit per sample) by the integral delta modulator (si gma_ (je 1-7a modulator) ll). ), M < N, and the quantization noise generated by households during the process will be pushed as far as possible to the south frequency outside the baseband via the loop (100p). 、 Phantom digital analog recons (cont noise) The corner digital is easy to be converted without clock. The M bit output of the delta modulator 110 (generally M value is bu 5) is converted into a staircase signal by the material level analog converter 120. Finally, the filter is reconstructed and filtered by an exchange capacitor. (S (: truct10n filter) 13 and continuous time reconstruction filter 2 noous time rec0nstructi0n futer) 14〇 Divide the fundamental frequency 3 to complete the analog audio signal reconstruction. However, the meta-analog conversion 5 | (卽 Μ -On the evening of August 81, the red m 77 ^ discrimination (that is, the product of M-1 is a diagonal digital analog converter) has a stable to instability), a limited analog in high operation and a digital analog of high frequency

Date of 1228011 __ __ Case No. 92117347 V. Description of the Invention (4) And because a large amount of fundamental quantization noise is generated at the integral delta modulator stage, a high-order low-pass is required after the digital analog converter output The filter filters this noise to a low enough level to avoid the siewing phenomenon of the audio amplifier (audio amp lifier) that may be connected in the future, causing intermodulation and harmonic distortion. , Which seriously affects the output sound quality. Multi-bit integral two-angle digital analog converters (including MASH DACs) can solve the problems of single-bit integral three-angle digital analog converters that are unstable, high operating frequency, and can reduce the order of low-pass filters at the back end. /

A general design using a multi-bit integral delta-digital analog converter. After integral delta modulation (sigma-delta m〇dulati〇n), the number of bits (the: bit n ^ n ^ ber) is less than 5 bits. (Including 5 bits) (that is, Figure 2M < = 5), outside the fundamental frequency, the power of the signal power (power) is still at a relatively high level, so it cannot be completed. Ί = Change the valley filter stage (SCF Stage). How to design a low-noise crosstalk, valley wave, and the key to the performance of the overall digital analog conversion system. turn

In addition, in multi-channel applications, the switching capacitor filter stage of the converter is not easy to improve the competitiveness of the product has become a problem. Since the traditional integral triangular digital analog is shared, how to further reduce the cost? A new multi-channel digital analog conversion is crying. In view of this, the present invention provides a system and an output method thereof.

Page 11 1228011

3. Summary of the Invention: The present invention proposes a new multi-channel high-resolution high-quality digital analog converter system. This multi-channel digital analog conversion system receives a multi-channel high-resolution digital audio source 'in the middle of digital interpolation, and converts a Nyquist-rate PCM digital audio source to a multiplied sampling PCM digital provincial source (〇 ¥ 6 Factory 3311 ^ 16 (1.00% (1121131311 (11〇). Then, use a low-order sigma-delta modulator) ^ Subtract

Reduce the sample ffordlength to be 10 ~ 14-bit. The output of the integral delta modulator is then converted into a multi-channel analog ladder waveform output by a shared resistor-string DACs, and finally a low-order active Rc low-pass filter is connected to each channel. To reconstruct the analog audio signal. • The present invention reduces the multiple sets of resistor strings required for multi-channei reustontring DACs to a common set. Avoiding the use of multiple sets of resistor strings and reducing the level of the electric modulator is only reduced by a suitable amount. Uncovering the birth-e — The length of the sub-sampling sample to reduce the number of string resistors required in the common resistance string, while maintaining the phase AL Θ, m | L ^ ^ The noise energy is extremely low, so after the common resistance string digital class 屮 44 is converted, the plurality of switching electric valley filters can be directly omitted (the stage of c, u, · λ.. ^. g οί switched-capacitor filters), just plural low-order 眈

$ 12 pages 1 π ff 1228011 ^ 92117347 V. Description of the invention (6) " Low-pass filter can perfectly reconstruct multi-channel audio signals. Due to the shared resistor string and the omission of the switched capacitor filter stage, this architecture is able to enjoy low-cost household potential and provide multi-channel high-quality audio output. -^ In the present invention, in order to overcome the shortcomings of digital analog converters such as low-speed communication and poor distortion, the common resistance string can be increased. ^ ^ Absolute random geometric deviation in the process of low resistance divides the resistance string. Influence of pressure accuracy. Mainly combined with the frequency doubling sampling technology, the harmonic caused by the mismatch of the string resistance = ^ True = S is spread over a wider frequency band to improve the total harmonic distortion effect in the fundamental frequency. (丁 η performance) 0 For the South resolution For digital sound source input, the present invention combines the integral delta modulation technology to reduce the long sound of sampling characters input by the digital analog converter of the common resistance string to 14 bits, so as to reduce the number of string resistances required for the common resistance string and save the resistance area. It also helps to resolve high-resolution multi-channel application / route complexity. m " In the present invention, the integral delta-modulator stage maintains a high bit output (the integral low-order output of the integral delta-delta modulator of a phase-integrated integral delta-digital analog converter), so the out-of_band quantizat -i〇; n〇ise) is at a very low level, which can completely omit the switching capacitor filter stage required to integrate the three analog conversion states. And the present invention has an oversampling rati0 is Mgh ^ enough. For example, the oversampling rati0 is Mgh ^ enough.

1228011 _ Case No. 92117347 A month day 绦 正 5. Description of invention (7)

The images at multiples of the sampl · rate and the base frequency interval have been far from the baseband, and have been filtered by the zero-order hold low-pass function of the digital analog converter of the common resistor string. Phase I ¥ low (are reduced to quite a small amount due to the filtering of zero ~ 〇rder-hold lowpass function 〇the shared resistor-string DACs), so only one sound is required after sharing a resistor string analog converter. A low order RC low-pass filter for each channel

Build multi-channel audio signals. J

A multi-channel shared resistor string digital analog converter system of the present invention includes: a time-sharing interconverter (T ime-sharing interp0lat0r). Converting the multi-channel digital audio input at some sample rate into a multi-channel digital audio output at R multiples o the input sample rate; —Time-sharing integration Time-sharing sigma-delta modulator. The time-sharing sigma-delta modulator is used to modulate the multi-channel digital sound source ^ output through the time-sharing upconverter. Short (with a shc ^ ter sample word 1 ength), multi-channel digital audio source output with high-frequency quantization noise; a multi-channel shared resistor string digital analog converter, the above multi-channel shared resistor string digital analog converter It is used to convert its multi-channel digital audio source input to a multi-tone type of staircase signal output; and

W. '/ L Page 14 1228011 __Case No. 92117347_ Year and Month _ _ Amendment _ V. Description of the Invention (8) · A plurality of low-order RC filters. Noise in the multi-channel analog ladder signal outside the baseband, especially the residual image, is further attenuated to complete the reconstructed output of the multi-channel analog audio signal. A multi-channel shared resistor string digital analog converter system according to the present invention includes: a time-sharing interpolator, which is used to convert an input multi-channel digital audio source Sampling frequency up-conversion R times output (converting the multi-channel dig / tal

audio input at some sample rate into a multi-channel digital audio output at R multiples 〇the input sample rate); —Multi-channel common resistor string digital analog test, the multi-channel common resistor string digital analog converter is used To convert its multi-voice digital sound source input into a multi-channel analog step signal output; and, a plurality of low-order RC filters, the plurality of low-order Rc filters are located at the fundamental frequency of the multi-channel analog step signal ( baseband), leave $ for further attenuation to complete the multi-channel analog audio signal re-^^ 0

The present invention :: Multi-channel common resistance string digital analog conversion conversion. A multi-acoustic reverberation, the use of resistance string digital analog repetition of sound, and the use of a resistance string digital analog converter system are used to convert a multi-channel audio frequency converter. Convert to -multi-channel analog staircase signal output; with a complex '::: pass filter', the above-mentioned high-order low-pass filter is used to produce the above

1228011 _ Case No. 92117347_ Year Month Day _ Amendment V. Invention Description (9). The residual image of the multi-channel analog ladder signal outside the baseband is further attenuated to complete the multi-channel analog audio signal. The reconstruction output. · One of the ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ multi-channel common digital analog conversion of multiple resistor strings, which includes The resistor string is shared, and the upper and lower resistor strings provide the required voltage level (v〇Hage levels) for each channel. One = = code. The decoder is used to receive a modulation U-bit number; = number of bits Signal;-a plurality of switches, the above-mentioned "seven on the shore two, the decoder is connected; each of the-a plurality of above-mentioned opening and closing position J number ίϊί L voltage level" and the above-mentioned decoder inputs _ the corresponding resistance string: Voltage: When a corresponding switch is turned on, 'Phase-Phase (buffers quasi-output), and a plurality of buffers quasi-buffer round out. The buffer is used to set the output voltage of each channel Implementation method: A block diagram of a multi-channel shared resistance string for the system shown by analogy to the moon. To τ :: digital analog converter 20. It is a multi-channel analogy, which is converted to a multi-channel analogy. More information can be used in the establishment of the digital audio source. V resistor string two of the common resistor string in real ^ vMultipie resistor

1228011 fix

MM 92117. ^ 7 V. Description of the invention (10) Number of two resistors. The 16-bit shared resistor string can be converted into two resistor strings digitally by analogy, "," and (. Each resistor string contains (28) = 256 string resistors, so only 512 string resistors are needed in total. From two to two, the common resistor string is used to avoid digital analog conversion of multi-channel resistor strings, mu 1 channel resistor-string Μ〇5) the disadvantages of using multiple sets of electric strings, so the area of multi-channel resistor strings can be greatly reduced ,,,,,,,,,, a plurality of high-order low-pass filters 2 1 0 are used to further attenuate the residual image meaning of the above-mentioned multi-channel analog 卩 White Ladder ^ at the fundamental frequency "" ^ ⑽ ", To complete the reconstruction output of the multi-channel analog audio signal. The above-mentioned high-order low-pass chirp waver 2 1 0 is, for example, a high-order RC filter 21. FIG. 2 is a block diagram of another digital analog conversion system of a multi-channel shared resistor string according to the present invention. 1. time-sharing

interpolator) 2 20 series is used for upsampling output of a multi-channel digital audio input. The sample w ^ rdlength of the multi-channel digital audio source input may be 16, 18, 20, 22, 24, or other current and future high-resolution audio standards. bit nUmber). The sampling rate FN_in of the multi-channel digital audio input is up-converted by R times by the time-sharing upconverter 220, that is, the sampling rate becomes RFN-in, and the output sample wordlength is basically maintained. Same as the original input, or slightly longer than the sampled character length of the original input. Frequency doubling sampling can reduce the common resistor string digital analog converter in the present invention

Page 17 1228011 ----- Plug No. 92117347 ____ Month Day Amendment V. Matching requirements of the invention description (11). ^ The above-mentioned multi-channel shared resistor string digital analog converter 230 is used to convert a signal of a multi-sound digital source into a multi-channel analog step signal output. As mentioned above, multiple resistor strings can be used in practical applications to reduce the number of resistors. Taking the 16-bit shared resistor string digital analog converter as an example, the shared resistor string can be divided into two resistor strings, each of which contains (2 8) = 2 5 6 string resistors, so only 5 1 2 are needed in total String resistance. Because the common resistor string used in the present invention avoids the shortcomings of multi-channel resistance digital string analog converters (multi-channei resistor — string daCs) detecting the use of resistor strings, the multi-channel resistance can be greatly reduced. String area. 4. In addition, a plurality of low-order low-pass filters 240 are used to further attenuate the residual images outside the baseband in the above multi-channel ^ ladder signals to complete multi-channel analog audio signals. The reconstruction output. The low-order low-pass filter 240 is, for example, a first-order RC filter 240. Figure 4 is a block diagram of another multi-channel shared resistor string digital analog converter system of the present invention. Of which time-sharing upconverter (Time — sharing

interpolator) 3 00 is used to upsample and output a multi-channel digital audio input. The sample word length (sampie w ^ diength) of the multi-channel digital audio input may be 16, 18, 20, 22, 24, or other present and future number of bits proposed by the South Audio Standard

1228011 Case number 92117347 V. Description of the invention (12) (bit number). The above multi-channel digital audio input is up-converted by the time-sharing upconverter 300, which means that | | h 丰 —n ,,, 二 山 抱 样 a-said "that is, the sampling rate becomes RFN-in , And the 轺 j ΐ temple at the sub-length (〇UtPUt: Sample W〇rdlenMh) basically remains the same as the original input's or slightly larger than the original input sample word ^ West Τ A ^ resistance string digital analog converter string Resistance matching requirements (Time — sharing sigma_deHa

Edulat〇r) 31 (M ^, used to modulate the multi-channel digital sound source input of 300 times up-converted by the above-mentioned time-sharing upconverter, with a shorter sample wordlength, containing Multi-channel digital sound source output of high-frequency quantization noise. The above-mentioned time-sharing integral delta modulator 3 (re-quantization q, Uant ize) is an N-bit sampling frequency RFli η from the time-sharing upconverter 3 00. The digital sound source input becomes the multi-channel digital output of the I-bit sampling frequency "I" '" < N. The quantization noise generated during the requantization process is adjusted to a high frequency through a loop as much as possible. Low fundamental noise and low harmonic distortion

Different from the output of 5 or less bits (including 5 bits) of the general integral delta modulator, the output of the integral delta modulator 31 of the present invention can be as high as ~ 14 bits. It is assumed that the output of the integrating delta modulator 3 is 0 bits, and the integrating triangle is assumed. After the week: the noise transfer function of the device 310 ^ heart "transfer functi〇n) is a ^ — 1) 2 'in the fundamental frequency external quantization noise caused by the integral triangle modulator 3 1 0 (the out-of-band quantization

Page 19 1228011

Case No. 92117347 V. Description of the invention (13) Noise power) is less than -71 h R r ^ η 〇, Gogu 丨 Wei 1, Shi Yu: dB (6.02 * 12-1 · 76 +3 dB) (relative full scale Sine wave input volume (rela1: i. L υ tne rul1-scale sinusoidal input power)) 〇 芒 4- 艟 哭哭 日 #a-&amp; The right side uses a general integration triangle digital analog toss converter and integrates two-tone tone The second output M5 bit of the variable crying age φ and noise π-is the &lt; column, then the fundamental frequency quantization noise month b 罝 is about -28 dB (-6.02 * 5-1 76 +3 dB). Please refer to FIG. 5, where the area below the solid line to the horizontal axis in the _ seeking <卩 # # ϋ aH / · # &gt; v I is the integral triangle modulation cry of the present invention 3]

And step green "Tβ soil Θ 71 branch of dl0 output of the fundamental frequency of external noise energy; the amount, and the surface below the dashed line to the axis of inspection 彳 ,, J six-eight-α β Jibei] is a general integration triangle Digital analog converter ,, Ba,. · "Shan Xin knows the noise energy of 5 shells. Therefore, although the" ntermedlate "stage of the present invention uses the integral delta modulator 31 () to reduce the sampling length, it still maintains 10 ~ 14 Bit output. Therefore, the quantization noise = dimension? In the phase: low position, can be noisy, general integral triangle • bit analog conversion, and = exchange electric valley filter stage. Because of the integral triangle modulator 3丨 〇 only reduces the number of bits, so it can reduce the order of the integral delta modulator 3 丨 〇 and oversamp sampling rate (oversampUng rati〇), for the integral triangular modulator 310 time sharing (Time-sharing) helps a lot.

Even channel common resistor string digital analog converter 3 2 0 can convert the multi-channel digital sound source output through the above-mentioned time-sharing integration delta modulator 3 丨 0 into multi-channel analog staircase outputs ), Please refer to Figure 4. In other words, the multi-channel output of the integrated trigonometric modulator 310 passes through the multi-channel shared resistor string.

Page 20 V. Description of the invention (14) After the digital analog converters (Shared resistor-string DACs) are converted to multi-channel analog ladder waveform output. The above-mentioned multi-channel shared resistor string digital analog conversion module includes a shared string, a plurality of decoders, a plurality of switches, and a plurality of buffers. _To give a detailed example: The output of the time-sharing integral delta modulator 3 J 〇 is 3 yuan (in the past, it is 10 to 14 bits), and the present invention uses the ρ channel 3 bit sharing Resistor string digital analog converter, as shown in Figure 6. The above-mentioned 500, 510, 5 20, 530, 540, 550, 5 60, and 57 ° provide a series of voltage levels. There are two or two L-channel channels in a channel digital analog converter. The decoder 580 receives the modulated 3-bit digital input signal and outputs 8 digital signals. Only one digit of the eight digital signals will cause the corresponding one of the switches to open, for example, switches 59, 6, 61, 62: "0, 650, and 6 60. The digital signals that open the switch pass through the phase: The electrical resistance level of the corresponding resistance string is passed through a buffer (_ 67〇: an analog ladder waveform. The above-mentioned switches 590, 600, 61, 6, 20, and) are 640, 6 50, and 6 60. For example, it is a metal oxide semiconductor transistor or a CMOS switch. 、 The decoder 680 that generates the signal of the Gongniu electric power channel and receives the modulated 3-bit digital input, outputs it. 8 digital signals. 8 digital signals will make a switch lever opposite to the shore „plus eight of θ have a digital signal switch, such as switches 690, 700, 720, 730, 74, 75 and 75 76. Number of switch on 1228011 _ Case No. 92117347 _ Month and month __ Amendment ____ V. Description of the invention (15) The signal passes the voltage level of the corresponding resistor string, and a buffer (buf fer) 770 outputs a Analog ladder waveform. The switches 690, 700, 710, 720, 730, 740, 750, and 760 are, for example, MOS or CMOS switches (MOS or CMOS switches). The common resistor string in Figure 6 is used in multiple applications (Multiple resistor-strings) to reduce the number of resistors. Taking a 12-bit-shared resistor-string digital analog converter as an example, the common resistor string can be divided into two types of resistor strings. Each resistor Each string contains (2 6) = 6 4 string resistors, so the total is only _ 1 28 string resistors. Since the present invention adopts a common resistor string, and combines frequency doubling sampling and integral dihedral modulation techniques to reduce the number of string resistors required for the common resistor string, the resistance area can be greatly reduced. In addition, for the shortcomings of poor linearity of the resistor string digital converter, increase the series resistor surface and product, and use frequency doubling sampling to improve it. Increasing the area of the string resistor can reduce the relative random geometric deviation of the resistor in the manufacturing process, and improve the precision of the resistor string voltage division. 1 doubling the sampling rate, the harmonic distortion energy caused by string resistance mismatches (pοwer 〇f harmonic distortion) can be resolved

wider bandwidth), in order to raise the United States = = wide frequency band (SPreaCl in U

am; with &amp; rise in the fundamental frequency

performance in the baseband). Astronomy this UHD due to the digital analog conversion of the integrated delta modulator 3 j 〇 32 f to hold 10 to 14 bit output, ^ quantized outside the fundamental frequency with very low energy: 1 analog output ladder wave Only bn is included in this category. This is heavier than the audio signal. 1228011 Amendment No. 92117347 V. Description of the invention (16) 3 It is necessary to consider the image at an integer multiple of the sampling frequency (i. Through the common resistor string digital analog converter 32. sampling_maintaining function二 ㈣ (sample-and-holf functi〇n) 'has been filtered to a certain amount, such as ^ 2 2 kHZ digital audio source (48kHz digi tal audio) as an example, and the fundamental frequency of the rabbit is 0 ~ 20 kHz, Attached Table 1 is the minimum attenuation value caused by the sampling-and-maintaining function to the image under different sampling rates of multiplier. From the attached Table 1, if the sampling frequency of the multiplier is 32, the minimum attenuation value is 37. 60 dB. Octave sampling rate 8 1 632641 28 Minimum decrement (dB) 25. 2431 · 4737. 6043 · 6749. 72

Then, the analog ladder output of each channel of the resistor string digital analog converter 32 is used to finally attenuate the residual image through a low-order RC filter 33 0. Please refer to FIG. The above-mentioned low-order Rc filter 33 ° is, for example, a first-order chirp filter 3 3 0 °. The image must be filtered to a low enough amount through the sample-and-maintain function to prevent the subsequent stage from entering the swing mode. The octave sampling rate is actually not feasible. Therefore, with a low-order low-pass filter, the residual image filtered by the sampling function is maintained to a sufficiently low level. If the octave sampling rate is sufficient to separate the image from the fundamental frequency, a simple Rc filter can be used. For an example, a 48 kHz digital sound source uses a frequency doubled sampling rate of 32, and a -3 dB frequency located at 48 kHz first-order RC filter 330, then the common resistor string digital analog converter 32 0 sample-and-hold function The first order rc filter 33 〇 The minimum attenuation value of the image is 67.70dB, winter

1228011 Amendment No. 92Π7347 V. Explanation of the invention (17) The filtering of the image is enough. The present invention also includes a digital analog output method for multi-channel shared resistor string. The above method includes: First, a one-time upconverter is used. For it, I (time-sharing 4) 邛 131; 〇; 〇3〇〇 Upsampling frequency of an input multi-channel source sampling frequency R times output; then, using a time-sharing integration three = · transformer 3 The 10 modulation is tuned out through the multi-channel digital tone of the above-mentioned time-sharing upconverter 300, which has a shorter sample character length (with a shorter sample, rain word 1 ength), and contains a lot of high-frequency quantization noise. Channel digital sound source wheel / Then, a multi-channel shared resistor string digital analog converter 32 is used to drag and drop the multi-channel digital sound source output through the time-sharing integral delta modulator 31 〇 as an audio signal output; ^ The post-utilization-multiple filters 330 further attenuate the above-mentioned analog audio signal at the fundamental frequency, especially the residual image, to complete the reconstructed output of the above-mentioned analog audio signal. The present invention further includes a Polyphonic Channel common resistor string digital analog converter | Output method, the above method includes the following: First, use a one-time upconverter ... ^ = in t '1 a t 2 2 G will be the multi-channel digital input ^ source of The sampling frequency is up-converted by R times. Then, M uses a multi-channel common resistor 1-bit f ratio converter 230 to convert through the above time-sharing up-converter 2; above the J two U sound source output is a multi-channel Analog audio signal output, then = :: a low-order low-pass filter 2 4 0 to the above-mentioned multi-channel analog audio signal outside the baseband (baseband) noise, especially on page 24 1228011-case number 92117347 r___ V. Description of the invention (18)-The residual image is further attenuated to complete the reconstruction output of the above-mentioned multi-channel analog audio signal. The present invention also includes a multi-channel shared resistor string digital analog converter. Rotating method. The above method includes: first, using a multi-channel common resistance string digital analog converter 2000 to convert a multi-channel digital audio source signal into a multi-channel analog audio signal output; then, using a complex number High-order low-pass filters 2 1 Attenuate the residual image of the above-mentioned multi-channel analog audio signal outside the fundamental frequency (dasease) to complete the reconstruction output of the above-mentioned multi-channel analog audio signal. The main advantages of the present invention include the following points : 1 · Multi-channel resistor string voltage divider digital analog converter shares a set of voltage divider resistor strings, which can save the resistance area. 2 · Multi-channel shared resistor string digital analog converter is reduced through frequency doubling sampling and integral delta modulation technology. The number of string resistors required for the common resistor string; ^ further reduces the resistance area and facilitates routing in multi-channel applications. 3. Through the frequency doubling sampling, the digital string analog conversion of the common resistor string can reduce the matching requirements of the resistor string. 4. The common resistance string and integration triangle have been greatly reduced, so each (variations) can be increased to cause the resistance string voltage division. 5. In the integration triangle modulation technology, the adjustment required for the digital delta-sigma analog converter is still required. Variable technology, the number of series resistors required to improve the shortcomings of insufficient precision of the process variation. 0 High bit output, can omit the general product

Page 25

6 · The low digital clock frequency and resistor string shared by the car driver can reduce the power consumed by the digital part and the resistor string (p0Wer dissipation). 7. Use a low-order RC filter, such as a first-order low-pass ^ filter, to filter out high-frequency residual images. God asks you to make changes as detailed as you can. The real kind of clear / likely contends that the description is compared with the example and the actual version is better than the unpackaged version in the modified and improved hair removal method. Take on both on and though. The cover is like the god, the god is overthrowing the essence of the essence, the essence of the essence, and the interpretation of the essence. The modification of the technical limitation of the off-limits is to repair the sample. \ No, the use of this interpretation is a non-work, to the knowledge and inside the widely used in its surroundings. However, Fan Li is the best. Case change

1228011 on page 26-The case number diagram briefly explains the purpose of the present invention, and the plaintext is supplemented by the following figure Z, the advantages and preferred embodiments will be explained in more detail in the following few articles: '' First Figure 疋A typical system block diagram of a conventional technology *; one-channel integral delta-digital analog converter

The second figure is a block diagram of a converter system according to the present invention; the third figure is a block diagram of a converter system according to the present invention; the fourth figure is a block diagram of a converter system according to the present invention; the fifth figure is an angular digital analog conversion according to the present invention Comparison of the signal energy of the transmitter; the digital analog of the multi-channel shared resistance string displayed is converted to the digital of the multi-channel shared resistance string displayed; Transformer and traditional integral three-integral delta modulator caused by the external frequency of the fundamental frequency &amp; sixth picture 疋 according to the present invention is not intended to change; the multi-channel shared resistor string digital analog to the seventh picture is based on this Schematic diagram of residual mirror image at the rate shown in the invention. The sampling frequency is compared to the stepped waveform at integer multiples. The symbol comparison table is shown as follows: Upconverter (interp〇iat〇r) i〇〇 Integral diagonal modulator (sigma-delta modulator) 110 Low-bit digital analog converter 1 2 〇

Page 27

1228011 Case No. 92Π7347

J correction: The diagram briefly explains the exchange capacitor reconstruction filter 1 3 0 continuous time reconstruction filter 1 4 0 multi-channel common resistance string digital analog converter 200, 23, 32, multiple high-order low-pass filters 2 1 0 Time-sharing interpolator 220, 300 Multiple low-order RC filters 240, 330 Time-sharing integral delta modulator 3 1 0 Resistance 500 -510 &gt; 52 0 &gt; 530 , Decoders 580, 680 switches 59 0, 60 0, 610, 62 0, 700 &gt; 710 &gt; 720 &gt; 730, 740 buffers 67 0, 770 540, 550 &gt; 560 '570 630' 640, 650 &gt; 750 v760 660 ^ 690

Page 28

Claims (1)

1228011 92117347 6 、 Applicable patent scope 1 · -Multi-channel common resistors-; Digital common analog of common channel resistors = turn = system, including: a digital f ratio converter is used to count the multi-channel number two Second, the earphones share a common channel and output a multi-channel analog audio signal; and the signal from 9 sources is converted into a plurality of high-order low-pass filters. The multi-channel analog signal is located in the United States # &lt; Let ’s take a look at $ 1 Niu Xiyu, the baSeband, and the remaining in-to reduce the weight of the multi-channel analog audio signal =: enter 2 · as in the patent application scope of the multi-channel multi-channel Shared resistance converter system, φ β &amp; string digital analog / turn-off T 3 common resistance string digital analog conversion, analog audio signal output is a multi-channel analog ladder waveform output ° 耷This type (multi-channel analog staircase waveform ♦ = is called, and the plurality of high-order low-pass filters are a plurality of high-order anxieties3. For example, the multi-channel shared resistor string digital analog converter system of the first patent application scope ' The multi-channel shared power The resistor-string digital analog converter includes: a resistor string, which is used as a common resistor string required for the multi-channel, and the resistor string provides the voltage level required for each channel ( voltage levels); a plurality of decoders, which are used to receive a modulated M-bit digital input signal and output 2 M digital signals; a plurality of switches, the plurality of switches and the resistor string, the The decoder is connected to 1228011-level 92117347_ month said Kaibu_16. The scope of patent application &quot; connection, where the mother-to-many switches correspond to the voltage level of the resistor string, and the decoder outputs 2M digital signals Only a digital signal causes a corresponding switch to be turned on, and the digital signal is output through the voltage level of the corresponding resistance string; and a plurality of buffers are used for the Selected voltage output level buffer output. 4. = Multi-channel shared resistor string digital analog / converter system for patent application No. 3, where the switch is a metal-oxygen semi-transistor Complementary metal-oxide-semiconductor (MOS or CMOS) switch. 5 · A multi-channel shared resistance string digital analog converter system, including: an interpolator, which is used to convert The sampling frequency of an input multi-channel digital audio source is up-converted by R times and output; a multi-channel shared resistor string digital analog string digital analog converter is used to convert this into a multi-channel analog audio signal output converter. Channel common resistance multi-channel digital sound source signal conversion; and: several low-order low-pass filters, the low-order low-pass filters are used for this purpose, located in the baseband Residual image outside of) for further attenuation 'to complete the reconstruction output of multi-channel analog audio signals. Work: Digital analog conversion of multi-channel shared resistor string in item 5 of the patent &quot; where the upconverter (i n t e r p 〇 1 a t 〇 r) is a one-minute upconverter Page 30 1228011 __ Case No. 92117347_Amended in January __ Sixth, the scope of patent application (Time-shari ng in ter po lat or), and the multi-channel analog audio signal output of the common resistor string digital analog converter is A multi-channel analog staircase waveform outputs, and the plurality of low-order low-pass filters are plural. Shared resistor string digital analog converter system, wherein the multi-channel shared resistor string digital analog conversion includes: a) a resistor string (shared resistor string), the resistor string is used as the multi-channel required sharing A resistor string, which provides the voltage levels required for each channel; a plurality of decoders, which are used to receive a modulated M-bit digital input signal and output 2M digital signals ; A plurality of switches, the plurality of switches are connected to the resistor string and the decoder; w each of the plurality of switches corresponds to the switch and the decoder outputs a 2 M digital signal corresponding to the switch On, the voltage level output of the digits; and a plurality of buffers (buffe) 0, the voltage output level buffers the output. A voltage level of the resistor string, and only a digital signal in the numerator makes a phase signal That is, through the corresponding resistor string, the buffer is used to digitally convert the selected electric circuit. 1228011 _ Prime No. 92117347 --- Yue Yue Zheng_ VI. Patent application scope of the converter system 'where the $ Hai switch is a metal-oxide-semiconductor or complementary metal-oxide-semiconductor (MOS or CMOS) switch . 9 · A multi-channel shared resistor string digital analog converter system including: a time-sharing interpolator, which is used to sample an input multi-channel digital audio source Frequency up-conversion R times output; a multi-channel shared resistance string digital analog converter, the multi-channel shared resistance string digital analog conversion state is used to play the signal of the multi-channel digital audio source into a multi-channel Analog audio signal output; and a plurality of low-order RC filters, the low-order RC filters are used to further reduce the residual image of the analog signal of the channel outside the baseband to complete the The reconstructed output of the multi-channel analog audio signal. 1 · If the multi-channel common resistance string digital analog converter system of item 9 of the patent application scope, wherein the multi-channel analog audio signal output of the common resistance string digital analog converter is a multi-channel analog staircase waveform output (multi-channel analog staircase waveform outputs), and the plurality of low-order RC filters are a plurality of first-order Rc filters.彳 心 &lt; Π · If the multi-channel shared resistance string of the patent application No. 9 is used 壑 仏 Analogy Han Korean system ‘where the multi-channel shared resistance string digital analog wheel 4 h f switch package Page 1228011 _ Case No. 921〗 7: U7 6. Patent application scope: a resistor string (Shared resistor string), which is used to provide the common resistor string required for the multi-channel, and the resistor string provides each sound The required voltage level (voltage leveis); ， Earth force a plurality of decoding states 'The decoder is used to receive a modulated M-bit digital input signal and output 2M digital signals; a plurality of switches' the complex number Each of the switches and the resistor string and the decoder corresponds to the voltage level of the resistor string, and the decoder outputs only one digital signal out of 2M digital signals such that 2 corresponds to the switch When turned on, the digital signal is output through the corresponding voltage level of the resistor string; and a plurality of buffers are used to buffer output the selected voltage level. 1 2 · If the multi-channel common resistance string digital analog converter system of the π item of the patent application scope, the switch is a metal-oxide-semiconductor or complementary metal-oxide-semiconductor (MOS or CMOS) switch. 1 3. — A multi-channel shared resistor digital string converter (DACs) system, including: an up-converter (interpolator), which is used to input an input The sampling frequency of multi-channel digital audio source is up-converted and r times output; Page 33 1228011 Amendment No. 92117347 Sixth, the patent application scope of the modulator (modulator), the modulator is changed through the wide, multi-channel digital audio source output, becomes a shorter sample character length • xi and amp ; * sh ^ te1 * samPle wordUngth), multi-channel digital sound source output with high-frequency quantization noise; ^ channel shared resistor string digital analog converter, the multi-channel shared resistor ^ digital analog converter is used to convert The signal of the multi-channel digital audio source is converted into a multi-channel analog audio signal output; and a plurality of filters, the filters are used for the noise of the multi-channel analog signal located outside the baseband, In particular, the residual image is attenuated by one step to complete the reconstructed output of the multi-channel analog audio signal. 1 4 · The multi-channel common resistance string digital analog converter system of item 13 of the scope of patent application, wherein the multi-channel analog audio signal output of the common resistance string digital analog converter is a multi-channel analog ladder Waveform output (multi-channel analog staircase waveform outputs) 'and the interpolator is a time-sharing interpolator, and the modulator is a one-time integral delta modulation (Time-sharing sigma-de 1 ta modulator), and the plurality of filters are a plurality of first-order "filters. 1 5 · Such as the multi-channel shared resistor string digital analog converter of the patent application No. 13 System, wherein the multi-channel common resistor string digital analog converter includes: a shared resistor string, which is used for Page 34 1228011 ____ Case No. 92117347 Amendment Date: 6. The scope of the patent application is the common resistor string required for the multi-channel, and the resistor string provides the voltage levels required for each channel; A plurality of decoders, which are used to receive a modulated M-bit digital input signal and output 2 μ digital signals; a plurality of switches' the plurality of switches are connected to the resistor string and the decoder; Each of the plurality of switches corresponds to the voltage level of the resistor string, and only one digital signal mirror of the 2M digital signals output by the decoder makes a corresponding switch open, and the digital signal passes through the corresponding The voltage level output of the electrical string; and a plurality of buffers, the buffers are used to buffer the selected lightning voltage level.电 f 电 1 6 · — A multi-channel shared resistor string digital analog converter system, including: a time-sharing interpolator, which is used to input multiple sounds The sampling frequency of the digital audio source is up-converted. R Angle Tuning: Time-sharing sigma-delta one-time integration * OJL Valley Ilia — UCl ια i ^ dulat ^ O, the time-sharing integration delta modulator is used to adjust After passing through this point = up to 5 Hz digital audio source output in the up frequency state, it becomes the sampling character length comparison: = Ash0 / ter sample wordlength), digital audio source output with high frequency quantization noise λ evening sound; digital converter, The multi-channel shared resistance channel digital audio source converts a multi-channel shared resistance string digital analog to digital converter to convert the multi-channel digital analog converter. Page 1228011 Case No. 92117347 VI. The scope of patent application is a multi-channel analog audio signal output; and a plurality of first-order RC filters, which are used to locate the multi-channel analog signal at the baseband (baseband) The external noise, especially the residual image, is further attenuated to complete the reconstructed output of the multi-channel analog audio signal. '1 7 · If the multi-channel common resistor string digital analog converter system of the 16th patent application range is applied, the multi-channel analog audio signal output of the common resistor string digital analog converter is a multi-channel analog ladder Waveform output $ / (multi-channel analog staircase waveform outputs) ° '1 8 · As in the patent application No. 丨 6, the multi-channel shared resistance string digital analog converter system, wherein the multi-channel shared resistance string digital analog system The converter includes ···, a resistor (Shared resistor string), the resistor string is used for the multi-channel shared resistor string, and the resistor string provides each dance, the required voltage level ( v〇l tage levels); ear, all the plurality of decoders, the decoder is used to receive a modulated M-bit input signal and output 2M digital signals; a script of a plurality of switches, the plurality of switches and The resistor string, the solution is connected, each of the plurality of switches corresponds to the voltage level of the resistor string, and only one digital signal out of the 2M digital signals output by the decoder makes 丄 = Correction _ Pass the corresponding resistance string 1228011 --- Case No. 921T 7347_ Year____S VI. The switch corresponding to the scope of patent application is turned on, the digital signal is transmitted through the voltage level output; and a plurality of buffers A buffer (buffer) is used to buffer the output voltage level of the operation. 1 9 · If the multi-channel common resistance string digital analog converter system of item 8 of the patent application scope, wherein the switch is a metal oxide semiconductor or complementary metal oxide semiconductor (MOS or CMOS) switch ( switch) 〇 / 2〇 · —A multi-channel shared resistor string digital analog converter output method, including: using an up-converter (interpolator) to "round-in multi-channel digital audio source sampling frequency up-conversion R times output; A modulator modulates the multi-channel digital sound source output passing through the upconverter to become a shorter sampling character (with a shorter s: fairy, containing high-frequency quantization noise using a multi-channel sharing The multi-channel digital audio source of the resistor string digital analog converter turns out as a ~ converter to convert through the tuning *; ^ ", multi-channel analog audio signal output Use a plurality of filters to reduce the noise of the multi-channel baseband, especially the base-frequency reduction in the residual intelligence ratio ^, to complete the multi-channel analog audio _ = mirroring, for further attenuation 4 Reconstruction output of years old. Page 37 1228011 __Case No. 92117347_Year_Month__ VI. Patent application scope ~ 2 1 · As in the patent application scope of the multi-channel common resistance string digital _ ratio converter output method, the upconverter ( interpolator) is a time-sharing interpolator, and the modulator is a time-sharing sigma-delta modulator, and the common resistor string is digitally converted by analog. The multi-channel analog audio signal output is a multi-channel analog staircase waveform outputs, and the plurality of filters are a plurality of first-order RC filters. / 22 · If the output method of the multi-channel common resistor string digital analog converter of the scope of the patent application is No. 20, wherein the multi-channel common resistor string digital analog converter includes:. '♦ To a resistor string (Shared resistor string), the resistor string is used as a common resistor string required for the multi-channel, and the resistor string provides the voltage levels required for each channel (v〇ltage levels); a plurality of decoders, the decoder It is used to receive a modulated M-bit digital input signal and output 2M digital signals; a plurality of switches, the plurality of switches are connected to the resistor string and the decoding; 吒 Among them, one of the plurality of switches corresponds to one The voltage level of the resistor string, and only one digital signal out of the 2M digital signals output by the decoder makes one = the corresponding switch is turned on, the digital signal passes through the corresponding voltage and the voltage level Quasi-output; and a plurality of buffers (buf f er), the buffers are used for the selected power 1228011 ---- Case No. 92117347 6. Scope of patent application Pressure level buffer output. Amendment 23 · The output method of the multi-channel converter according to item 22 of the scope of the patent application, where the switch is ~ /, a digital analog MOS or CMOS transistor with a resistor string is off, &gt; Crystal or complementary J switch. 24 · — A variety of multi-channel common resistor string digital classes include: Than the converter output method using an upconverter (interpolator) to ~ ~ / sampling frequency upconverted I? Times the output; The source uses a multi-channel shared resistor string digital frequency synthesizer, and the multi-channel digital audio source output is output; and a converter is used to convert the multi-channel analog audio signal input using a plurality of low-order low-pass The filter is particularly attenuated to noises outside the multiple basebands, especially the residual attenuation, so as to complete the multichannel analog audio signal and the channel analog signal is left in the image for further reconstruction output. 2 5 · The output method of the multi-channel shared resistor string digital analogue as claimed in the May 24th patent scope, where the upconverter (interp〇lat〇r) sharing interpolator), and the multi-channel analog audio signal output of the shared resistor string digital analog converter is a multi-channel analog staircase waveform outputs, and the plurality of low-order low-pass filters The filter is a plurality of first-order RC filters. 1228011 Case No. 92117347 VI. Application for Patent Scope 26 · The output method of the multi-channel shared resistance string digital analog converter such as the 24th in the patent application 'where the multi-channel shared resistance string digital analog converter includes: a resistor string (Shared resistor string), the resistor string is used as a common resistor string required for the multi-channel, and the resistor string provides the voltage levels required for each channel; a plurality of decoders, the The decoder is used to receive a modulated M-bit digital turn-in signal and output 2M digital signals; j a plurality of switches, the plurality of switches are connected to the resistor string and the decoding; Each of the plurality of switches corresponds to the voltage level of the resistor string, and the decoder outputs only one digital signal out of the 2M digital signals to make a corresponding switch open, and the digital signals pass through the corresponding The voltage level output of the resistor string; and a plurality of buffers, the buffers are used to buffer the selected voltage level for output. 2 7 · The output method of the multi-channel shared resistance string digital analog converter according to item 26 of the patent application, wherein the switch is a metal-oxide-semiconductor or complementary metal-oxide-semiconductor (MOS or CMOS) switch (switch ). 2 8 · —A kind of multi-channel shared resistance string digital analog converter output method, including: 1228011 _ case number 92117347_ year month_R VI. Patent application scope '~ ^-using a multi-channel shared resistance string digital The signal of the analog sound source is converted into a multi-channel analog audio signal. The multi-channel digital uses a plurality of high-order low-pass filters to obtain the extra signal. Residual images outside the band) are further + "," "Γ," the reconstructed output of the multi-channel analog audio signal. | 'Xian Yifan Cheng 29. The multi-channel common resistance string digital analog conversion output method as described in the 28th item of the patent application scope, wherein the multi-tone 迢 analog audio signal output of the common resistance string digital analog converter is a multi-tone Channel analog staircase waveform output (multi-channel analog staircase waveform output s) 'and the plurality of high-order low-pass filters are a plurality of high-order "filters." 4 ^ 30. Such as the multi-channel of the 28th patent application The output method of a common resistor string digital analog converter, wherein the multi-channel common resistor string digital analog converter includes: — a shared resistor string, which is used as a common resistor required for the multi-channel And the resistor string provides the voltage levels required for each channel;-a plurality of decoders, which are used to receive a modulated M-bit digital input signal and output 2M digital signals A plurality of switches, which are connected to the resistor string and the decoder; wherein each of the plurality of switches corresponds to the voltage level of the resistor string, and 1228011 --ΛΜ 92117347 Health a j --- Charm-Sixth, the scope of patent application 'and the decoder output only one digital signal out of 2M digital signals makes a phase, the corresponding switch is turned on, the digital signal is transmitted through the corresponding The voltage level output of the resistor string; and a plurality of buffers, the buffers are used to buffer the selected electrical level. 3 1 · If the output method of the multi-channel shared resistance string digital analog converter according to item 30 of the patent application scope, wherein the switch is a metal-oxygen semi-transistor or a metal-filled gas semi-transistor (MOS or CMOS) switch ( switch). 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