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1. 发明授权

US5621632A Switch mode power supply circuit 失效
标题翻译：开关电源电路
公开(公告)号：US5621632A
公开(公告)日：1997-04-15
申请号：US316493
申请日：1994-09-30
申请人： Kian P. Hoh , Chun H. Wu
发明人： Kian P. Hoh , Chun H. Wu
IPC分类号： H02M3/335 , H02M7/5375 , H04N5/63
CPC分类号： H04N5/63 , H02M3/33523 , H02M2001/0032 , Y02B70/16
摘要： In a switch mode power supply of a video apparatus, a capacitor develops a supply voltage that is coupled to a main current conducting electrode of a driver transistor. The driver transistor drives a switching power transistor. An arrangement charges the charging capacitor when the video apparatus operates in standby mode. A delay circuit introduces a delay time between a time when the capacitor begins to be charged and the time when a switching control signal is applied to the driver transistor for operation in a run mode. Consequently, the capacitor develops sufficient voltage that insures sufficient base current to turn on the power transistor in to saturation prior to the time the switching control signal is applied to the driver transistor. Thus, a possible damage to the power transistor is prevented.
摘要翻译：在视频装置的开关模式电源中，电容器产生耦合到驱动晶体管的主电流传导电极的电源电压。驱动晶体管驱动开关功率晶体管。当视频设备在待机模式下工作时，一种布置对充电电容器进行充电。延迟电路在电容器开始充电的时间和切换控制信号施加到驱动晶体管以在运行模式下操作的时间之间引入延迟时间。因此，电容器产生足够的电压，确保足够的基极电流在将开关控制信号施加到驱动晶体管之前将功率晶体管导通至饱和。因此，可以防止功率晶体管的可能损坏。

2. 发明授权

US5198731A Linearization of vertical reference ramp 失效
标题翻译：垂直参考斜坡的线性化
公开(公告)号：US5198731A
公开(公告)日：1993-03-30
申请号：US898271
申请日：1992-06-15
申请人： Chun H. Wu
发明人： Chun H. Wu
IPC分类号： H03K4/72 , H03K4/90 , H04N3/233
CPC分类号： H04N3/233 , H03K4/72 , H03K4/90
摘要： A vertical deflection ramp voltage is generated by the charge and discharge of a resistor capacitor combination. The voltage ramp is coupled to an amplifier which drives a current through a deflection coil producing a magnetic deflection field. The ramp voltage produced by the resistor capacitor combination has an inherent exponential shape which is linearized to prevent vertical linearity errors in the deflected electron beam. Linearization is achieved by multiple feedback paths which couple the amplifier output voltage and a voltage sample of the deflection coil current to the ramp forming resistor. These feedback signals are of a polarity such to establish a constant voltage across the resistor which consequently produces a constant current flow through the resistor. Hence with constant current flow in the resistor, a linear voltage ramp is produced across the capacitor and exponential deflection cramping is avoided. The voltage sample of the deflection coil current is coupled from the wiper of a potentiometer, which by other coupling produces degenerative feedback and provides control of deflection amplitude or height.
摘要翻译：通过电阻电容器组合的充放电产生垂直偏转斜坡电压。电压斜坡耦合到放大器，其驱动电流通过偏转线圈产生磁偏转场。由电阻器电容器组合产生的斜坡电压具有固有的指数形状，其被线性化以防止偏转的电子束中的垂直线性误差。通过将放大器输出电压和偏转线圈电流的电压样本耦合到斜坡形成电阻器的多个反馈路径实现线性化。这些反馈信号具有极性，以便在电阻器两端建立恒定的电压，从而产生通过电阻器的恒定电流。因此，在电阻器中具有恒定的电流流动，电容器之间产生线性电压斜坡，避免了指数偏转钳制。偏转线圈电流的电压样本从电位器的擦拭器耦合，电位计通过其它耦合产生退化反馈并提供偏转幅度或高度的控制。

3. 发明授权

US5291386A Switched mode power supply with precharge of base-emitter sweep-out capacitor 失效
标题翻译：具有基极 - 发射极扫除电容器预充电的开关电源
公开(公告)号：US5291386A
公开(公告)日：1994-03-01
申请号：US918533
申请日：1992-07-22
申请人： Chun H. Wu
发明人： Chun H. Wu
IPC分类号： H04N3/18 , H02M3/00 , H02M7/5375 , H04N3/185 , H04N5/63
CPC分类号： H04N3/185 , H04N5/63 , H02M2001/0032 , Y02B70/16
摘要： A television receiver has a switched mode power supply for regulating an output voltage, including a power transformer having a primary winding coupled to an unregulated voltage via a power transistor. The power transistor is controlled by pulses from the output of a controller. In order to sweep the base-emitter charge from the power transistor in order to end collector-emitter conduction, the base of the power transistor is coupled to the output of the pulse generating controller via a capacitor in parallel with at least one diode. During a pulse from the controller, the capacitor is charged to a voltage equal to the forward biased drop across the diode(s). At the end of a pulse at the output of the controller, the voltage across the capacitor provides a negative voltage at the base of the transistor, thus sweeping out the base-emitter charge and sharply turning the transistor off. In order to assure this function of the capacitor even upon plug-in startup, the capacitor is precharged via a resistor coupled between the output of the controller and the unregulated voltage input.
摘要翻译：电视接收机具有用于调节输出电压的开关模式电源，包括具有经由功率晶体管耦合到未调节电压的初级绕组的电力变压器。功率晶体管由来自控制器的输出的脉冲控制。为了从功率晶体管扫描基极 - 发射极电荷以终止集电极 - 发射极传导，功率晶体管的基极通过与至少一个二极管并联的电容器耦合到脉冲发生控制器的输出端。在来自控制器的脉冲期间，电容器被充电到等于二极管上的正向偏置电压的电压。在控制器输出端的脉冲结束时，电容器两端的电压在晶体管的基极处提供一个负电压，从而扫除基极 - 发射极电荷并急剧地关闭晶体管。为了确保即使在插入启动时电容器的功能，电容器也通过耦合在控制器的输出端和未调节的电压输入端之间的电阻进行预充电。

4. 发明授权

US5270823A Run/standby control with switched mode power supply 失效
标题翻译：运行/待机控制与开关模式电源
公开(公告)号：US5270823A
公开(公告)日：1993-12-14
申请号：US906872
申请日：1992-07-02
申请人： Wolfgang Heidebroek , Chun H. Wu
发明人： Wolfgang Heidebroek , Chun H. Wu
IPC分类号： H04N3/185 , H04N5/63
CPC分类号： H04N5/63 , H04N3/185 , H02M2001/0032 , Y02B70/16
摘要： A television receiver has a switched mode power supply for regulating output voltages including the B+ output to a flyback transformer, by generation of output pulses to a power transformer. A controller for the power supply is coupled in two feedback loops, one responsive to a pulse width modulator coupled to the flyback transformer and the other comparing the output voltage with an internal reference for free running operation. The first feedback loop takes precedence and is active in the run mode of the television receiver. In the standby mode when horizontal rate pulses are absent, the second feedback loop takes over. The second feedback loop has a different reference level than the first, such that when switching from the run mode to the standby mode a transition interval occurs in which no pulses are output by the controller, thereby causing the B+ voltage to the flyback transformer to fall. During this transition interval, horizontal scanning signals continue at falling amplitude, and a signal is input to the kinescope drivers, thereby collapsing the picture and draining the ultor voltage on the screen anode. The reoccurrence of controller pulses when the output voltage of the power transformer has fallen to the new lower reference level is used to positively switch operation of the receiver at the conclusion of the transition interval.

5. 发明授权

US5491794A Fault protection using microprocessor power up reset 失效
标题翻译：使用微处理器上电复位进行故障保护
公开(公告)号：US5491794A
公开(公告)日：1996-02-13
申请号：US376691
申请日：1995-01-23
申请人： Chun H. Wu
发明人： Chun H. Wu
IPC分类号： H04N3/20 , H04N5/63 , G06F11/00
CPC分类号： H04N3/20 , H04N5/63 , H02M2001/0032 , Y02B70/16
摘要： In a television receiver, a microprocessor controls a horizontal deflection circuit which is coupled to run mode power supply to define a standby operating mode and a run operating mode. The microprocessor has a power-up reset input terminal which initializes operation upon application of AC mains power. The run mode power supply is coupled to at least one load which is subject to overcurrent or overvoltage faults. A fault detection circuit detects fault conditions in the run mode power supply loads such as overvoltage or overcurrent and anomalous vertical deflection current. Upon fault detection the fault detection circuit triggers a power up reset circuit which applies a momentary reset pulse to the power-up reset input of the microprocessor. Upon receipt of the reset pulse, the microprocessor controls the horizontal deflection circuit to place the run mode power supply in the standby operating mode. Thus power is removed from the run mode load subject to the overvoltage or overcurrent or anomalous condition, and the television receiver assumes a standby condition.
摘要翻译：在电视接收机中，微处理器控制水平偏转电路，其耦合到运行模式电源以定义备用操作模式和运行模式。微处理器具有上电复位输入端，其在施加AC电源时初始化操作。运行模式电源耦合到至少一个受到过流或过压故障的负载。故障检测电路检测运行模式电源负载（如过电压或过电流和异常垂直偏转电流）中的故障状况。在故障检测时，故障检测电路触发上电复位电路，该电路将瞬时复位脉冲施加到微处理器的上电复位输入。在接收到复位脉冲时，微处理器控制水平偏转电路以将运行模式电源置于待机操作模式。因此，能够从运行模式负载中移除受到过电压或过电流或异常情况的电力，并且电视接收机处于待机状态。

6. 发明授权

US5331347A Television sync and phase detector disable circuit 失效
标题翻译：电视同步和相位检测器禁用电路
公开(公告)号：US5331347A
公开(公告)日：1994-07-19
申请号：US898880
申请日：1992-06-15
申请人： Chun H. Wu
发明人： Chun H. Wu
IPC分类号： G11B7/00 , G11B7/0045 , G11B7/005 , G11B7/0055 , G11B7/125 , H04N5/04 , H04N5/06 , H04N5/12 , H04N5/44
CPC分类号： H04N5/126
摘要： A television receiver is subject to certain operational conditions which result in poor, unreliable or unusable separated sync pulse signals. During such conditions the use of unsuitable sync signals for synchronization and the like is inhibited to prevent mis-triggering or spurious synchronization. A television receiver contains circuitry for extracting a sync signal, a voltage controlled oscillator (VCO) for generating a scanning signal, and a comparator comparing the scanning signal to the separated sync signal. A microprocessor is used to verify the separate sync signal for invalid or unusable signals and has an output activated during such conditions. The phase comparator has a current output coupled to a integrating capacitor or LPF which develops a varying positive or negative voltage to raise or lower the frequency of the VCO for scanning in phase with the separated sync. During conditions of unusable separated sync pulse signals, the microprocessor output causes the integrating capacitor or LPF to be coupled to a voltage source for forcing the VCO to a maximum frequency. Also, during periods of unusable sync the microprocessor decouples the separated sync signal from the vertical deflection generating circuit, allowing the vertical deflection generating circuits to free run. Setting the horizontal frequency to a maximum value and inhibiting vertical deflection synchronization eliminates instability of on-screen displays during periods of unusable sync.
摘要翻译：电视接收机受到某些操作条件的影响，导致差的，不可靠的或不可用的分离的同步脉冲信号。在这种情况下，禁止使用不合适的同步信号进行同步等，以防止误触发或伪同步。电视接收机包括用于提取同步信号的电路，用于产生扫描信号的压控振荡器（VCO）以及将扫描信号与分离的同步信号进行比较的比较器。微处理器用于验证单独的同步信号，用于无效或不可用的信号，并在这种情况下激活输出。相位比较器具有耦合到积分电容器或LPF的电流输出，该积分电容器或LPF产生变化的正或负电压以升高或降低VCO的频率，以便用分离的同步进行同相扫描。在不可用的分离同步脉冲信号的条件下，微处理器输出使积分电容器或LPF耦合到电压源，以迫使VCO达到最大频率。此外，在不可用的同步期间，微处理器将分离的同步信号与垂直偏转发生电路解耦，允许垂直偏转发生电路自由运行。将水平频率设置为最大值并禁止垂直偏转同步消除了不可用同步期间屏幕显示的不稳定性。

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