US 7,397,230 B2 · Integrated FET synchronous multiphase buck converter with innovative oscillator

Abstract

A power conversion system, preferably a buck converter, having (i) an oscillator, (ii) a pulse width modulator, (iii) and a nonoverlap clock generator and level shifter, wherein the improvement comprises the elimination of an external resistor divider is described. The buck converter can convert input voltage ranging from approximately 3V to 5V down to approximately 0.7-1.0V, 1.2V, 1.5V, 1.8V, 2.5V, and 3.3V without the use of resistor dividers. The voltage input identifiers select one of the possible output settings for flexibility and accuracy. The integrated field emitting transistors can provide a continuous current of at least 6 A. Additionally, peak current mode and an oscillator enable multiphase operation, up to ten buck converters, for up to 60 A output current. The multiphase operation reduces the output inductor size, and number of bulk capacitors. Moreover, the multiphase operation yields higher efficiency and provides high transient response for demanding applications.

Claims15

Dependent claims

An integrated field emitting transistor buck converter for down converting a first voltage to a lower, second voltage, the buck converter comprising:

an oscillator for producing a periodic clock signal, the oscillator comprising a first input, a first output, a second output, and a third output;
a soft start circuit for enabling a smooth start and voltage sequencing, the soft start circuit comprising a first input coupled to the first output of the oscillator, and a first output;
an error amplifier for amplifying a first signal, the error amplifier comprising an inverting input, a non-inverting input, and a first output;
a ramp generator for amplifying a second signal, the ramp generator comprising a first output;
and
a pulse width modulator for holding a frequency constant while the width of a power pulse is varied, the pulse width modulator comprising a first input coupled to the second output of the oscillator, a second input coupled to the first output of the soft start circuit, a third input coupled to the first output of the error amplifier, and a fourth input coupled to the first output of the ramp generator.

3 more elements

A power conversion system comprising:

a first buck converter comprising:
a first connection (CLKIN) for receiving a clock signal;
a second connection (CLKOUT) for outputting a clock signal;
a third connection (ENSS) for enabling a soft start;
a fourth connection (COMP) for outputting an error amplifier output;
a fifth connection (FB) for receiving inverting input for the error amplifier;
a sixth connection (Vid0) for a receiving first output voltage identifier;
a seventh connection (Vid1) for a receiving second output voltage identifier;
an eighth connection (GND) for coupling to a ground signal;
a ninth connection (PGND1) for coupling to a first power ground signal;
a tenth connection (PGND2) for coupling to a second power ground signal;
an eleventh connection (PHASE1) for outputting a first phase output;
a twelfth connection (PHASE2) for outputting a second phase output;
a thirteenth connection (PHASE3) for outputting a third phase output;
a fourteenth connection (PHASE4) for outputting a fourth phase output;
a fifteenth connection (BOOST) for outputting a bootstrap output;
a sixteenth connection (PVdd1) for receiving a first power supply for power stage;
a seventeenth connection (PVdd2) for receiving a second power supply for power stage;
an eighteenth connection (Vdd) for receiving a voltage supply signal;
a nineteenth connection (SLOPE) for receiving a voltage slope;
and
a twentieth connection (SYNC) for receiving an external clock signal.

19 more elements

Dependencies are inferred from the claim text.

Integrated FET synchronous multiphase buck converter with innovative oscillator

Life of this patent

Integrated FET synchronous multiphase buck converter with innovative oscillator

Life of this patent

Abstract

Claims15