# US 9,882,474 B2 · Multi-mode controlled power converter

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 9,882,474 B2
- Document ID: US9882474B2
- Status: Granted
- Kind: B2
- Application number: 14/889,285
- Filed: 2014-05-23
- Published: 2016-05-05
- Granted: 2018-01-30
- Earliest claimed: 2013-05-24
- Assignees: IDT Europe GmbH
- Applicants: Idt Europe GmbH
- Inventors: Richard Maria Schmitz; Eric Marschalkowski; Chris Young
- Web page: https://patentgrep.com/patent/US9882474B2

## CPC

- H02M 3/157: with digital control
- H02M 1/0032: {Control circuits allowing low power mode operation, e.g. in standby mode}
- H02M 1/0035: {using burst mode control}
- Y02B 70/10: Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes
- 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)
- Y02B: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS

## Abstract

A switched power converter includes a switchable power stage for generating an output voltage according to a switching signal and an input voltage via a switching element. The switching signal is generated by a multi-mode controller. The multi-mode controller controls a digital control path for generating a pulse width modulation switching signal and a constant-on-time control path for generating a constant-on-time switching signal. The switching signal for controlling the switching element is generated in the digital control path when the multi-mode controller is run in a high load mode. The switching signal is generated in the constant-on-time control path when the multi-mode controller is run in a light load mode.

## Claims

### Claim 1

A switched power converter comprising a switchable power stage for generating an output voltage according to a switching signal and an input voltage via a switching element, the switching signal being generated by a multi-mode controller, said multi-mode controller controlling a digital control path for generating a pulse width modulation switching signal and a constant-on-time control path for generating a constant-on-time switching signal, wherein the switching signal for controlling the switching element is generated in the digital control path when the multi-mode controller is run in a high load mode and wherein the switching signal is generated in the constant-on-time control path when the multi-mode controller is run in a light load mode, and wherein the digital control path is disconnected from power supply when the multi-mode controller is run in light load mode, wherein the constant-on-time control path further comprises a minimum-off-time circuit configured to compute a sum of constant-on-time and a minimum-off-time, and wherein the multimode controller is configured to activate the digital control path when the sum of the constant-on-time and the minimum-off-time is not greater than a normal period of the pulse width modulation switching signal.

### Claim 2 (depends on 1)

The switched power converter according to claim 1, wherein the multi-mode controller is configured to determine executing the light load mode or the high load mode from a load current or by monitoring the output voltage.

### Claim 3 (depends on 1)

The switched power converter according to claim 1, wherein the digital control path comprises an error amplifier for amplifying a difference between the output voltage and a reference voltage for generating an error signal; an analog to digital converter to convert the error signal into a digitized error signal; a PID compensator to generate a pulse width modulation duty cycle according to the digitized error signal; and digital pulse width modulator for generating the pulse width modulation switching signal.

### Claim 4 (depends on 3)

The switched power converter according to claim 3, wherein the error amplifier, the analog to digital converter, the PID compensator and the digital pulse width modulator are adjustable with respect to bandwidth by the multi-mode controller.

### Claim 5 (depends on 1)

The switched power converter according to claim 1, further comprising a multiplexer for multiplexing the switching signal between the constant-on-time switching signal and the pulse width modulation switching signal, said multiplexer controlled by the multi-mode controller.

### Claim 6 (depends on 1)

The switched power converter according to claim 1, wherein the constant-on-time path comprises a comparator and a constant-on-time circuit, wherein the comparator is configured to compare the output voltage with a reference voltage and wherein the comparator is connected to the multi-mode controller and the constant-on-time circuit.

### Claim 7 (depends on 1)

The switched power converter according to claim 1, wherein the switchable power stage comprises a third switching element to short-circuit an inductor for draining an excessive inductor current.

### Claim 8 (depends on 1)

The switched power converter according to claim 1, further comprising a driver with zero current detection to drive the switching element according to the switching signal.

### Claim 9

A method for controlling a switched power converter comprising a switchable power stage switched according to a switching signal, the method comprising:
generating a pulse width modulation switching signal in a digital control path when running the switched power converter in a high load mode;
disconnecting the digital control path from a power supply, and generating a constant-on-time switching signal in a constant-on-time control path when running the switched power converter in a light load mode;
computing a sum of constant-on-time and a minimum-off-time with a minimum-off time circuit in the constant-on-time control path; and
activating the digital control path when the sum of the constant on-time and the minimum off-time determined in the constant-on-time control path is not greater than a normal period of the pulse width modulation switching signal.