Hybrid analog/digital point-of-load controller

#This application relates to the field of power control, and more particularly to a hybrid analog-digital point-of-load controller for an intelligent voltage source.

#In certain electrical configurations, it is desirable to maintain a substantially constant output voltage. This may be the case, for example in a power supply, power stage, power conditioner, voltage source, or other similar circuit, which are all referred to collectively herein as a “voltage source.” A theoretical ideal voltage source has infinite input impedance, zero output impedance, infinite current capacity, and infinite slew rate so that it can theoretically provide a constant output voltage v (for direct current) or v(t) (for alternating current), regardless of the load current being drawn. For convenience, the actual output voltage of a voltage source, whether alternating current or direct current, may be referred to throughout this specification as Vout, and the ideal output voltage may be referred to as V0.

#As a practical matter, a voltage source provides an imperfect time- or frequency-varying voltage. In the frequency domain, the output voltage may be described as Vout=V(s)=V0+Td(s)+K, where Td(s) represents a frequency-variant disturbance function and K represents a constant offset value. Both Td(s) and K may depend both on factors internal to the voltage source and external to the voltage source. Internal factors include for example leakage, internal noise, and offsets. External factors include for example timing, power demands including current transients, and feedback. Td(s) may also be dependent on noise in the circuit.

#The present disclosure is best understood from the following detailed description when read with the accompanying figures. It is emphasized that, in accordance with the standard practice in the industry, various features are not drawn to scale and are used for illustration purposes only. In fact, the dimensions of the various features may be arbitrarily increased or reduced for clarity of discussion.

#FIG. 1 is a block diagram of an intelligent voltage source according to one or more example embodiments of the present specification.

#FIG. 2 is a block diagram of a hybrid analog-digital point-of-load controller according to one or more example embodiments of the present specification.

#Overview

#In one example, there is disclosed a hybrid analog-digital point-of-load controller (ADPOL) for use in a power supply. The ADPOL is configured to respond to transient current loads. In the presence of moderate current loads, power is clocked by a digital power core, which may be programmatically configured to adjust pulse width in response to the transient load. In the presence of larger current loads, control may be passed to an analog transient compensator, which includes high-speed circuitry selecting between a very high-duty-cycle clock and a very low-duty-cycle clock, which will drive the transient back to the digital control domain.

#In another example, there is disclosed a hybrid analog-digital point-of-load controller for regulating an output voltage comprising: a programmable digital power core (DPC) configured to sense the output voltage, compare the output voltage to a reference voltage, and provide a DPC clock output; an analog transient compensator (ATC) configured sense the output voltage, and comprising: a clock generator configured to generate a high-duty-cycle clock and a low-duty-cycle clock; and a first selector logic operable to select an ATC clock comprising either the high-duty-cycle clock or the low-duty-cycle clock responsive to the output voltage; and a second selector logic for selecting between the DPC clock and the ATC clock.