摘要:
The present invention discloses an adaptive two-stage voltage regulator and a method for controlling the same. The adaptive two-stage voltage regulator includes: a voltage regulator for converting an input voltage (Vin) to a middle voltage (Vm), wherein Vin≦Vin_max; a linear regulator for converting the middle voltage to an output voltage (Vout); and a middle voltage controller for adjusting the middle voltage according to (1) an input voltage indicator and one of (2a) an output voltage indicator and (2b) a predetermined reference signal, such that when Vin≦Vout, Vm=Vout+ΔV and (Vout+ΔV)
摘要:
The present invention discloses a power converter with improved line transient, comprising: a power stage circuit including at least one power transistor switch which operates to convert an input voltage to an output voltage; an error amplifier comparing a feedback signal with a reference signal to generate an error signal; an input voltage instant variation extraction circuit extracting an instant variation of the input voltage and generating a signal relating to the instant variation; and a PWM comparator generating a PWM signal according to at least a ramp signal, the error signal, and the signal relating to the instant variation, to thereby control the operation of the power transistor switch in the power stage circuit.
摘要:
An LED driver includes a power converter to convert an input voltage to a regulated voltage, a current source to be connected with an LED string in series between the power converter and a bias node, and a switching circuit to apply a bias voltage to the bias node to set the total voltage drop of the LED string and the current source. By controlling the total voltage drop of the LED string and the current source, the LED driver will automatically select a boost mode or a buck mode for operation, thereby improving the efficiency thereof.
摘要:
The present invention discloses a power converter with improved line transient, comprising: a power stage circuit including at least one power transistor switch which operates to convert an input voltage to an output voltage; an error amplifier comparing a feedback signal with a reference signal to generate an error signal; an input voltage instant variation extraction circuit extracting an instant variation of the input voltage and generating a signal relating to the instant variation; and a PWM comparator generating a PWM signal according to at least a ramp signal, the error signal, and the signal relating to the instant variation, to thereby control the operation of the power transistor switch in the power stage circuit.
摘要:
The present invention discloses an adaptive two-stage voltage regulator and a method for controlling the same. The adaptive two-stage voltage regulator includes: a voltage regulator for converting an input voltage (Vin) to a middle voltage (Vm), wherein Vin≦Vin_max; a linear regulator for converting the middle voltage to an output voltage (Vout); and a middle voltage controller for adjusting the middle voltage according to (1) an input voltage indicator and one of (2a) an output voltage indicator and (2b) a predetermined reference signal, such that when Vin≦Vout, Vm=Vout+ΔV and (Vout+ΔV)
摘要:
The present invention discloses a light emitting device driver circuit and a method for driving a light emitting device. The circuit comprises: a power stage performing power conversion on an input voltage to supply an output current to one or more light emitting devices; and a control circuit sensing the output current of the power stage to feedback control the power stage accordingly.
摘要:
Systems and methods for generating reference voltages are provided. A representative system comprises a resistor circuit; a first switch coupled between a first end of the resistor circuit and a first power source; a second switch coupled between the first end of the resistor circuit and a second power source; a third switch coupled to a second end of the resistor circuit; a fourth switch coupled to the second end of the resistor circuit; a first resistor coupled between the first end of the resistor circuit and the first switch; a second resistor coupled between the first end of the resistor circuit and the second switch; a third resistor coupled between the second end of the resistor circuit and the third switch; a fourth resistor coupled between the second end of the resistor circuit and the fourth switch; and a control circuit for controlling the switches.
摘要:
Systems and methods for generating reference voltages are provided. A representative system comprises a resistor circuit; a first switch coupled between a first end of the resistor circuit and a first power source; a second switch coupled between the first end of the resistor circuit and a second power source; a third switch coupled to a second end of the resistor circuit; a fourth switch coupled to the second end of the resistor circuit; a first resistor coupled between the first end of the resistor circuit and the first switch; a second resistor coupled between the first end of the resistor circuit and the second switch; a third resistor coupled between the second end of the resistor circuit and the third switch; a fourth resistor coupled between the second end of the resistor circuit and the fourth switch; and a control circuit for controlling the switches.
摘要:
Analog buffers with a precise gate to source voltage compensation and a small DC offset, by storing an input offset voltage to be used as an output offset voltage to reverse the offset in the input. A first source follower at the input end and a second source follower at the output end are both coupled to a switching circuit, wherein the first follower provides an input offset voltage (e.g., |Vgsp|) based on the input voltage (Vin), the second source follower provides an output voltage (Vout) by compensating Vin transmitted through the analog buffer circuit with an output offset voltage (|Vgsn|), and the switching circuit stores and equalizes the output offset voltage to the input offset voltage (|Vgsp|=|Vgsn|), so to obtain an output Vout that is identical to Vin.
摘要:
Systems and methods for generating reference voltages are provided. A representative system comprises a resistor circuit; a first switch coupled between a first end of the resistor circuit and a first power source; a second switch coupled between the first end of the resistor circuit and a second power source; a third switch coupled to a second end of the resistor circuit; a fourth switch coupled to the second end of the resistor circuit; a first resistor coupled between the first end of the resistor circuit and the first switch; a second resistor coupled between the first end of the resistor circuit and the second switch; a third resistor coupled between the second end of the resistor circuit and the third switch; a fourth resistor coupled between the second end of the resistor circuit and the fourth switch; and a control circuit for controlling the switches.