公开(公告)号：JPH0419723B2

公开(公告)日：1992-03-31

申请号：JP7904682

申请日：1982-05-11

Applicant: YAMAHA CORP

Inventor： NORO MASAO

IPC: H03F1/34 ,  H03F1/42 ,  H03F1/52

公开(公告)号：JPH02292799A

公开(公告)日：1990-12-04

申请号：JP11179989

申请日：1989-04-28

Applicant: YAMAHA CORP

Inventor： NORO MASAO

IPC: G11C27/00 ,  G11C27/02 ,  H03G3/20

Abstract: PURPOSE:To prevent a hold value from being changed due to the lapse of time by providing a rectifier means, a smoothing means, a capacitor to which the output of the smoothing means is supplied via a first rectifier element, and a second rectifier element connected in parallel with the first rectifier element also in a reverse direction, and taking out the output from the capacitor. CONSTITUTION:The output of the smoothing means 24 is supplied to the capacitor C3 via the first rectifier element D4, and is outputted as the hold value. When the output of the smoothing means 24 is decreased gradually by its time constant and it is decreased less than a value in which the voltage in forward direction of the second rectifier element D5 is subtracted from the voltage of the capacitor C3, the second rectifier element D5 is turned on, and the capacitor C3 is discharged to the smoothing means 24 via the second rectifier element D5. However, since the output of the smoothing means 24 reaches the value in which the voltage in forward direction of the first rectifier element D4 is added on the voltage of the capacitor C3 at an initial stage, no discharge of the capacitor C3 occurs until the output of the smoothing means 24 is decreased by the value in which the voltage in forward direction of the first rectifier element D4 is added on the voltage in the forward direction of the second rectifier element D5, then, the hold value can be held. In such a way, it is possible to prevent the hold value from being reduced.

公开(公告)号：JPH02182099A

公开(公告)日：1990-07-16

申请号：JP114789

申请日：1989-01-09

Applicant: YAMAHA CORP

Inventor： SUZUKI TAKUYA ,  NORO MASAO

IPC: H04R3/00

Abstract: PURPOSE:To improve sensitivity and an S/N without losing the frequency characteristic by connecting a negative impedance load means including a negative impedance reducing or invalidating the internal impedance of a microphone unit to an output terminal of the unit. CONSTITUTION:An output terminal and a noninverting input terminal of a negative resistance circuit 2 are connected between output terminals (a), (b) of a dynamic microphone unit 1. Since a voltage caused by an output current Iin of the unit 1 across a resistor R1 the negative resistance circuit 2 is fed back positively to the noninverting input terminal of an amplifier 21, an output impedance Zo becomes a negative resistance. Then resistors R1, R2 and R3 are selected properly to obtain a relation of Zo=-Rvc, then the internal resistance Rvc of the microphone unit 1 is completely invalidated. Thus, an output voltage Eo not affected with equivalent motional impedances Lu, Cu and Ru whose frequency characteristic is flat is obtained.

公开(公告)号：JPH01243847A

公开(公告)日：1989-09-28

申请号：JP7117088

申请日：1988-03-25

Applicant: YAMAHA CORP

Inventor： SUZUKI EIICHI ,  YOKOYAMA KENJI ,  NORO MASAO

IPC: H02M3/07 ,  H02M3/155

Abstract: PURPOSE:To prevent rush current, by changing ON pulses of driving pulses in level in accordance with the output of an output takeout means and by changing the ON state of a switching means in accordance therewith. CONSTITUTION:A boosting power source is equipped with a DC power source 40, a driving pulse generation means 42, a switching means 44, a charging- discharging means 46 and an output takeout means 48. This generation means 42 is composed of a square-wave oscillator 50 to produce a square-wave signal A of a predetermined cycle and its reversal circuit 52 and makes it a driving pulse. A diode 56 is connected between the DC power source 40 and a boosting power supply line 54, with which power is supplied to the above generation circuit 42. The switching means 44 is formed by MOS-type FET 62-65 and driven with the driving pulse abovementioned. Further, the charging-discharging means 46 is equipped with circuits 103 and 105 comprised of diodes, whose capacitors 92-94 and 104-106 are gradually charged, so that their rush current can be prevented.

公开(公告)号：JP2013093772A

公开(公告)日：2013-05-16

申请号：JP2011235211

申请日：2011-10-26

Applicant: Yamaha Corp ,  ヤマハ株式会社

Inventor： NORO MASAO

IPC: H04S1/00 ,  H04S5/02

CPC classification number: H04S3/002 ,  H04R5/04 ,  H04S2400/03

Abstract: PROBLEM TO BE SOLVED: To provide a signal processor in which a frequency characteristic does not greatly change even in the case of compounding a difference signal and a sum signal.SOLUTION: An L-R signal is inputted to an APF 14, and an L+R signal is inputted to a BPF 15. A circuit characteristic is set so that a frequency of the APF 14 causing a phase shift of 90 degrees and a center frequency of the BPF 15 have the same value (for example, 1 kHz). The circuit characteristic is set so that the BPF 15 has substantially the same phase characteristic as that of the APF 14. That is, there is set the circuit characteristic in which the frequency characteristic of the BPF 15 has a gentle and broad pass band and is matched with the phase characteristic of the APF 14, thereby holding a difference in phase between the APF 14 and the BPF 15 in a whole audible band.

Abstract translation: 要解决的问题：提供即使在混合差分信号和和信号的情况下频率特性也不会很大地改变的信号处理器。 解决方案：将LR信号输入到APF14，并且将L + R信号输入到BPF 15.电路特性被设定为使得APF14的相位偏移为90度的频率和 BPF 15的中心频率具有相同的值（例如，1kHz）。 电路特性被设定为使得BPF15具有与APF14基本相同的相位特性。也就是说，设置BPF 15的频率特性具有平缓和宽通带的电路特性，并且是 与APF14的相位特性匹配，从而在整个可听频带中保持APF14和BPF15之间的相位差。 版权所有（C）2013，JPO＆INPIT

公开(公告)号：JP2008278669A

公开(公告)日：2008-11-13

申请号：JP2007120674

申请日：2007-05-01

Applicant: Yamaha Corp ,  ヤマハ株式会社

Inventor： NORO MASAO ,  SHIMIZU TAKANORI

IPC: H02M3/00 ,  H03F99/00

CPC classification number: H02M3/156

Abstract: PROBLEM TO BE SOLVED: To provide a small power controller that achieves high-output drive by compensating power at a peak period even if using a power supply whose supply-power maximum value is small, a speaker device, and a power control method.
SOLUTION: In the speaker device, when output of an audio signal Sin temporarily becomes large and power consumption is increased, a DC-DC converter 11 increases an output current Iout by stepping down an output voltage Vout while increasing a supply current to an amplifier 12 by discharge from a capacitor C1. By this arrangement, it is possible to temporarily supply power of not lower than 2.5 W, supplied from a USB connection terminal 10, to the amplifier 12. It is also possible to make variations in voltage difference between both ends of the capacitor C1 large so as to increase a discharge amount from the capacitor C1. Consequently, it is possible to reduce the size of the capacitor C1.
COPYRIGHT: (C)2009,JPO&INPIT

Abstract translation: 要解决的问题：为了提供一种小功率控制器，即使使用供电功率最大值小的电源，扬声器装置和功率控制，也可以在高峰期补偿功率来实现高输出驱动 方法。 解决方案：在扬声器装置中，当音频信号Sin的输出临时变大并且功耗增加时，DC-DC转换器11通过降低输出电压Vout而增加输出电流Iout，同时增加供给电流 放大器12通过从电容器C1放电。 通过这种布置，可以将从USB连接端子10提供的不低于2.5W的功率临时提供给放大器12.还可以使电容器C1的两端之间的电压差变化较大，从而 从而增加来自电容器C1的放电量。 因此，可以减小电容器C1的尺寸。 版权所有（C）2009，JPO＆INPIT

公开(公告)号：JP2008035221A

公开(公告)日：2008-02-14

申请号：JP2006206450

申请日：2006-07-28

Applicant: Yamaha Corp ,  ヤマハ株式会社

Inventor： SUZUKI EIICHI ,  NORO MASAO

IPC: H03F3/68

Abstract: PROBLEM TO BE SOLVED: To detect a load current, even when the supply voltage of an amplifier circuit is relatively high.
SOLUTION: Currents I1 and I2 corresponding to a potential difference, generated in a resistance 50 for detection flow to transistors 63 and 64 constituting a current mirror circuit. Emitter currents are determined at relatively low potentials by a transistor 65; and when the difference of values of currents flowing to transistors 63 and 64 are generated, a current, corresponding to the portion of the change is supplied to the inversion input terminal of an operational amplifier 30. Potentials at the non-inversion input terminal and the inversion input terminal are regarded as equal to each other, and a potential equal to or higher than the breakdown voltage is not input to the operational amplifier 30. That is, a detection circuit 1 will operate normally, even when the supply voltage VDD of a BTL amplifier circuit are relatively high, since the breakdown voltages of transistors 64 and 65 to which relatively high potentials are applied as being amply higher than that of the operational amplifier 30.
COPYRIGHT: (C)2008,JPO&INPIT

Abstract translation: 要解决的问题：即使当放大器电路的电源电压相对较高时，也检测负载电流。 解决方案：对应于在构成电流镜电路的晶体管63和64的检测电流50中产生的电势差的电流I1和I2。 发射极电流由相对较低的电位由晶体管65确定; 并且当产生流向晶体管63和64的电流值的差异时，将对应于该变化的部分的电流提供给运算放大器30的反相输入端。非反相输入端和 反相输入端子被认为是相等的，并且等于或高于击穿电压的电位没有被输入到运算放大器30.即，即使当一个检测电路1的电源电压VDD BTL放大器电路相对较高，因为施加相对较高电位的晶体管64和65的击穿电压大大高于运算放大器30的击穿电压。（C）2008，JPO＆INPIT

公开(公告)号：JP2007110235A

公开(公告)日：2007-04-26

申请号：JP2005296587

申请日：2005-10-11

Applicant: Yamaha Corp ,  ヤマハ株式会社

Inventor： NORO MASAO ,  ARAI AKIRA

IPC: H04R1/02 ,  H04R1/28

Abstract: PROBLEM TO BE SOLVED: To increase and out a low band even when a speaker enclosure is small.
SOLUTION: When a speaker 10 is driven, the vibration of cone paper of the speaker 10 is propagated into air in the speaker enclosure 90 and the vibration region 91a of a diaphragm 91 is vibrated by the vibration of the air. Since the speaker 10 is fitted to the diaphragm 91, the sufficiently large vibration area of the diaphragm 91 can be obtained. In this case, the speaker 10 acts like the vibration load of the diaphragm 91, the speaker 10 can also have the function of suppression of other vibration modes than the primary vibration mode by the adjustment of the moment by its self-weight and the fitting position.
COPYRIGHT: (C)2007,JPO&INPIT

Abstract translation: 要解决的问题：即使扬声器外壳小，也可以增加和降低低频段。 解决方案：当扬声器10被驱动时，扬声器10的锥纸的振动传播到扬声器壳体90中的空气中，并且振动膜91的振动区域91a被空气的振动振动。 由于扬声器10安装在隔膜91上，所以能够得到振膜91的足够大的振动面积。 在这种情况下，扬声器10的作用与隔膜91的振动载荷一样起作用，扬声器10还可以通过其自重和配合来调节力矩而具有比主振动模式抑制其它振动模式的功能 位置。 版权所有（C）2007，JPO＆INPIT

公开(公告)号：JP2006101682A

公开(公告)日：2006-04-13

申请号：JP2004288204

申请日：2004-09-30

Applicant: Yamaha Corp ,  ヤマハ株式会社

Inventor： ISHIGAKI YUZO ,  NORO MASAO

IPC: H02M3/28

CPC classification number: H05B41/282

Abstract: PROBLEM TO BE SOLVED: To provide a power supply apparatus for an audio amplifier which eliminates respective defects of a low-frequency power supply transformer and a switching power supply, for use as audio amplifier.
SOLUTION: The switching power supply apparatus 1 can use a capacitor-less flyback converter circuit 5, provided with no smoothing input capacitor having a large capacity to suppress a power supply harmonics and to dispense with an inrush current preventing element, with reduction in the size and in the weight of the device; whereas the fluctuation in the output current Io to be supplied to a load 100 is fed back to the capacitor-less flyback converter circuit 5 at a speed smaller than the input AC frequency by a negative feedback circuit 8, so that the power factor can be improved making the input AC current, in proportion to the input AC voltage. Furthermore, since the voltage-controlled circuit 7 controls the output voltage to be applied to the load to a constant voltage, to lower the output voltage in proportion to the output current, when the output current to be supplied to the load exceeds a threshold value, this switching power supply apparatus can have the output characteristics to be the same as those of the power supply apparatus equipped with a low-frequency power supply transformer.
COPYRIGHT: (C)2006,JPO&NCIPI

Abstract translation: 要解决的问题：为了提供消除用于音频放大器的低频电源变压器和开关电源的各种缺陷的音频放大器的电源装置。 解决方案：开关电源装置1可以使用无电容反激式转换电路5，其不具有大容量的平滑输入电容器，以抑制电源谐波并且减少浪涌电流阻止元件，同时还原 在设备的尺寸和重量上; 而要提供给负载100的输出电流Io的波动通过负反馈电路8以比输入的AC频率小的速度反馈到无电容反激转换器电路5，使得功率因数可以 改善输入交流电流，与输入交流电压成比例。 此外，由于电压控制电路7将施加到负载的输出电压控制为恒定电压，与输出电流成比例地降低输出电压，所以当提供给负载的输出电流超过阈值时 该开关电源装置的输出特性与配备有低频电力变压器的电源装置的输出特性相同。 版权所有（C）2006，JPO＆NCIPI

公开(公告)号：JP2006060278A

公开(公告)日：2006-03-02

申请号：JP2004237047

申请日：2004-08-17

Applicant: Yamaha Corp ,  ヤマハ株式会社

Inventor： NORO MASAO ,  ASAHIRA HAJIME

IPC: H03F3/217 ,  H03F1/52 ,  H03F3/183

CPC classification number: H03F3/2173 ,  H03F1/52 ,  H03F2200/03 ,  H03F2200/471

Abstract: PROBLEM TO BE SOLVED: To securely detect a short circuit of a speaker output and to prevent an amplifier from being broken owing to a power source pumping phenomenon.
SOLUTION: A protecting circuit of a digital amplifier has: a DC voltage detecting circuit DCDT which detects a DC voltage generated at a speaker output terminal SPOUT; a control circuit CTL which performs protecting operation when the DC voltage detecting circuit DCDT outputs a detection signal; and a midpoint potential detecting circuit CVDT which detects deviation in midpoint potential between a positive source voltage +V and a negative source voltage -V. The output of the midpoint potential detecting circuit CVDT is connected to the input of the DC voltage detecting circuit DCDT to make the DC voltage detecting circuit DCDT output the detection signal when deviation in midpoint potential is detected.
COPYRIGHT: (C)2006,JPO&NCIPI

Abstract translation: 要解决的问题：为了可靠地检测扬声器输出的短路并防止放大器由于电源泵送现象而损坏。 解决方案：数字放大器的保护电路具有：检测在扬声器输出端子SPOUT处产生的直流电压的直流电压检测电路DCDT; 控制电路CTL，当DC电压检测电路DCDT输出检测信号时，执行保护动作; 以及中点电位检测电路CVDT，其检测正电源电压+ V与负电源电压-V之间的中点电位的偏差。 中点电位检测电路CVDT的输出与直流电压检测电路DCDT的输入端连接，使得当检测到中点电位偏差时，直流电压检测电路DCDT输出检测信号。 版权所有（C）2006，JPO＆NCIPI