# US 2008/0186006 A1 · Method and system for communicating filter compensation coefficients for a digital power control system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2008/0186006 A1 - Document ID: US20080186006A1 - Status: Published application - Kind: A1 - Application number: 11/778,647 - Filed: 2007-07-17 - Published: 2008-08-07 - Earliest claimed: 2002-12-21 - Assignees: Power-One, Inc. - Inventors: Alain Chapuis - Web page: https://patentgrep.com/patent/US20080186006A1 ## CPC - H02M 3/157: with digital control - H02J 1/08: Three-wire DC power distribution systems; Systems having more than three wires - H02J 1/082: DC supplies with two or more different DC voltage levels - H02J 13/1321: {using a wired telecommunication network or a data transmission bus} - H02J 13/34: the equipment being switches, relays or circuit breakers - H02M 3/33515: {with digital control} - H02J 1/102: being switching converters (H02J1/108, H02J1/12 take precedence) - H02M 1/0012: {Control circuits using digital or numerical techniques (in DC/DC converters H02M3/157, H02M3/33515; in DC-AC converters H02M7/53873)} - H02M 1/008: {Plural converter units for generating at two or more independent and non-parallel outputs, e.g. systems with plural point of load switching regulators} - H02M: APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF (transformers H01F; dynamo-electric converters H02K47/00; controlling transformers, reactors or choke coils, control or regulation of electric motors, generators or dynamo-electric converters H02P) - H02J: ELECTRIC POWER NETWORKS; CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY ## Abstract A method and system is provided for programming the digital filter compensation coefficients of a digitally controlled switched mode power supply within a distributed power system. The distributed power system comprises a plurality of point-of-load (POL) regulators each comprising at least one power switch adapted to convey power to a load and a digital controller adapted to control operation of the power switch responsive to a feedback measurement. The digital controller further comprises a digital filter having a transfer function defined by plural filter coefficients. A serial data bus operatively connects each of the plurality of POL regulators. A system controller is connected to the serial data bus and is adapted to communicate digital data to the plurality of POL regulators via the serial data bus. The digital data includes programming data for programming the plural filter coefficients. The system controller further comprises a user interface adapted to receive the programming data therefrom. ## Claims ### Claim at position 1 1-8. (canceled) ### Claim 9 A point-of-load regulator comprising: a power conversion circuit adapted to convert an intermediate voltage to an output voltage, said power conversion circuit comprising at least one power switch adapted to convey power to a load and a digital controller adapted to control operation of said at least one power switch responsive to a feedback measurement, said digital controller further comprising a digital filter having a transfer function defined by plural filter coefficients; a serial data bus interface adapted to communicate programming information from an external serial data bus connected thereto; and a controller connected to said serial data bus interface and said power conversion circuit, said controller being adapted to determine said plural filter coefficients from programming data received via said serial data bus interface. ### Claim 10 (depends on 9) The point-of-load regulator of claim 9, wherein said digital controller further comprises: an analog-to-digital converter providing a digital error signal representing a difference between said output measurement and a reference value, said digital filter providing a digital control output based on a sum of current and previous error signals and previous control outputs; an error controller adapted to modify operation of said digital filter upon an error condition; and a digital pulse width modulator providing a control signal to said at least one power switch, said control signal having a pulse width corresponding to said digital control output. ### Claim 11 (depends on 10) The point-of-load regulator of claim 10, wherein said analog-to-digital converter further comprises a windowed flash analog-to-digital converter. ### Claim 12 (depends on 11) The point-of-load regulator of claim 11, wherein said windowed flash analog-to-digital converter provides a HIGH signal reflecting a negative saturation of said analog-to-digital converter and a LOW signal reflecting a positive saturation of said analog-to-digital converter. ### Claim 13 (depends on 9) The point-of-load regulator of claim 9, wherein said digital filter further comprises an infinite impulse response filter. ### Claim 14 (depends on 13) The point-of-load regulator of claim 13, wherein said infinite impulse response filter provides the following transfer function G(z): G  ( z ) = PWM  ( z ) VEd  ( z ) = C 0 + C 1 · z - 1 + C 2 · z - 2 + … + C n · z - n 1 - B 1 · z - 1 - B 2 · z - 2 - … - B n · z - n wherein PWM(z) is the digital control output, VEd(z) is the error signal, C0 . . . Cn are input side coefficients, and B1 . . . Bn are output side coefficients. ### Claim 15 (depends on 10) The point-of-load regulator of claim 10, wherein said digital filter further comprises a range limiter adapted to clip said digital control output if upper or lower range limits are reached. ### Claim 16 (depends on 15) The point-of-load regulator of claim 15, wherein said range limiter provides a limit signal to said error controller if said upper or lower range limits are reached. ### Claim 17 (depends on 10) The point-of-load regulator of claim 10, wherein said digital controller further comprises a multiplexer coupled to said error controller and to said digital filter, said error controller providing an alternative digital control output to said multiplexer that passes to said digital pulse width modulator upon said error condition. ### Claim 18 (depends on 10) The point-of-load regulator of claim 10, wherein said error controller is further adapted to preset at least one of said previous error signals with predetermined values upon said error condition. ### Claim 19 (depends on 10) The point-of-load regulator of claim 10, wherein said error controller is further adapted to preset at least one of said previous control outputs with predetermined values upon said error condition. ### Claim 20 (depends on 10) The point-of-load regulator of claim 10, wherein said error controller is further adapted to reset at least one of said previous error signals to initial values upon said error condition. ### Claim 21 (depends on 10) The point-of-load regulator of claim 10, wherein said error controller is further adapted to reset at least one of said previous control outputs to initial values upon said error condition. ### Claim 22 (depends on 10) The point-of-load regulator of claim 10, wherein said error condition further comprises a saturation of said analog-to-digital converter. ### Claim 23 (depends on 10) The point-of-load regulator of claim 10, wherein said error condition further comprises a mathematical overflow of said digital filter. ### Claim at position 17 24-27. (canceled)