Power supply device and operating method thereof
A power supply device for supplying power to an electronic device. The power supply device includes a switched mode power supply (SMPS) comprising at least one switching element and configured to convert an input power input to the power supply device to the power supplied to the electronic device; and a controller configured to obtain a voltage and/or a current of the input power, determine a load of the electronic device based on the obtained voltage and/or current, and set a slew rate of the at least one switching element based on the obtained load.
1 . A power supply device for supplying power to an electronic device, the power supply device comprising: a switched mode power supply (SMPS) configured to convert an input power input to the power supply device to the power supplied to the electronic device, the SMPS comprising at least one switching element and a gate driver connected to the at least one switching element; a load acquiring unit configured to acquire at least one of a voltage of the SMPS and a current of the SMPS; and a controller configured to: determine a load of the electronic device based on the acquired voltage and/or current of the SMPS; adjust a slew rate of the at least one switching element based on the load; and adjust an operating frequency of the at least one switching element based on the load, wherein electromagnetic interference (EMI) caused by the at least one switching element having a first EMI frequency is generated when the power supply device operates at a first operating frequency, and the EMI having a second EMI frequency greater than the first EMI frequency is generated when the power supply device operates at a second operating frequency greater than the first operating frequency, and wherein the controller is further configured to change the slew rate of the at least one switching element in response to the EMI exceeding a predetermined EMI level.
2 . The power supply device of claim 1 , wherein the controller is further configured to:
increase the slew rate in response to a decrease of the load.
3 . The power supply device of claim 1 , wherein the controller is further configured to:
decrease the slew rate in response to an increase of the load.
4 . The power supply device of claim 1 , wherein the controller is configured to:
adjust the slew rate of the at least one switching element to a first value in response to the load being equal to or greater than a preset reference ratio of a maximum load of the electronic device by adjusting a resistance value of the gate driver controlling the at least one switching element, and
adjust the slew rate of the at least one switching element to a second value greater than the first value in response the load being less than the preset reference ratio of the maximum load by adjusting the resistance value of the gate driver controlling the at least one switching element.
5 . The power supply device of claim 1 , wherein the controller is further configured to:
increase the slew rate of the at least one switching element by decreasing a resistance value of the gate driver as the load decreases, and
decrease the slew rate of the at least one switching element by increasing the resistance value of the gate driver as the load increases.
6 . The power supply device of claim 1 , wherein the SMPS further comprises:
a bridge circuit to which the input power is applied;
an LLC resonant circuit connected to the bridge circuit; and
a power factor improving unit configured to improve a power factor of the input power and output the input power with the improved power factor to the bridge circuit,
wherein the load acquiring unit is configured to acquire at least one of an output voltage of the power factor improving unit and an output current of the power factor improving unit, and
wherein the controller is further configured to determine the load of the electronic device based on the acquired output voltage and/or output current of the power factor improving unit, and adjust the slew rate based on a resistance value of the gate driver based on the load of the electronic device.
7 . The power supply device of claim 6 , wherein the controller is further configured to:
decrease the slew rate as the voltage and/or the current of the power output from the power factor improving unit increases, and
increase the slew rate as the voltage and/or the output current of the power output from the power factor improving unit decreases.
8 . The power supply device of claim 1 , wherein the controller is further configured to:
determine the load of the electronic device every preset period, and
in response to a load acquired at a second time point later than a first time point being higher than a load acquired at the first time point, decrease the slew rate at the second time point by a predetermined magnitude, compared to the slew rate at the first time point.
9 . The power supply device of claim 1 , wherein the SMPS includes a half-bridge converter including a first switching element and a second switching element.
10 . The power supply device of claim 9 , wherein the controller is further configured to:
increase slew rates of the first switching element and the second switching element in response to a decreased load of the electronic device, and
decrease the slew rates of the first switching element and the second switching element in response to an increased load of the electronic device.
11 . The power supply device of claim 1 , wherein the controller is further configured to:
determine the load at a first time point,
determine the load at a second time point after the first time point,
in response to the determined load at the second time point being larger than the load at the first time point, decrease the slew rate of the at least one switching element by a predetermined magnitude, and
in response to the determined load at the second time point being smaller than the determined load at the first time point, increase the slew rate of the at least one switching element by the predetermined magnitude.
12 . The power supply device of claim 11 , wherein the controller is further configured to:
determine the load at a third time point after the second time point,
in response to the determined load at the third time point being larger than the load at the second time point, decrease the slew rate of the at least one switching element by the predetermined magnitude, and
in response to the determined load at the third time point being smaller than the determined load at the second time point, increase the slew rate of the at least one switching element by the predetermined magnitude.
13 . The power supply device of claim 1 , wherein in response to the load of the electronic device being a second value, the at least one switching element of the power supply device operates at the first operating frequency, and in response to the load of the electronic device being a first value less than the second value, the at least one switching element of the power supply device operates at the second operating frequency greater than the first operating frequency.
14 . The power supply device of claim 13 , wherein the EMI caused by the at least one switching element having the first EMI frequency is generated when the power supply device operates at the first operating frequency, and the EMI having the second EMI frequency greater than the first EMI frequency is generated when the power supply device operates at the second operating frequency greater than the first operating frequency.
15 . The power supply device of claim 14 , wherein the controller is further configured to decrease the slew rate of the at least one switching element in response to the EMI having the first EMI frequency exceeding the predetermined EMI level, and the controller is further configured to increase the slew rate of the at least one switching element in response to the EMI having the second EMI frequency exceeding the predetermined EMI level.
16 . A method of controlling a power supply device for supplying power to an electronic device, the method comprising: acquiring at least one of a voltage of the power supply device and a current of the power supply device; determining, via a controller of the power supply device, a load of the electronic device based on the acquired voltage of the power supply device and/or current of the power supply device; adjusting, via the controller, a slew rate of at least one switching element to a first value when the load is equal to or greater than a preset reference ratio of a maximum load of the electronic device by adjusting a resistance value of a gate driver controlling the at least one switching element; adjusting, via the controller, the slew rate of the at least one switching element to a second value greater than the first value when the load is less than the preset reference ratio of the maximum load by adjusting the resistance value of the gate driver controlling the at least one switching element; and adjusting, via the controller, an operating frequency of the at least one switching element based on the load, wherein electromagnetic interference (EMI) caused by the at least one switching element having a first EMI frequency is generated when the power supply device operates at a first operating frequency, and the EMI having a second EMI frequency greater than the first EMI frequency is generated when the power supply device operates at a second operating frequency greater than the first operating frequency, and changing the slew rate of the at least one switching element, via the controller, in response to the EMI exceeding the predetermined EMI level.
17 . The method of claim 16 , further comprising:
increasing the slew rate of the at least one switching element by decreasing the resistance value of the gate driver in a response to a decrease of the load; and
decreasing the slew rate of the at least one switching element by increasing the resistance value of the gate driver in response to an increase of the load.
18 . The method of claim 16 , wherein acquiring at least one of the voltage of the power supply device and the current of the power supply device includes at least one of
acquiring a voltage an input power input to the power supply device and/or a current of the input power input to the power supply device; and
acquiring a voltage of the at least one switching element and/or a current of the at least one switching element.
19 . The method of claim 16 , wherein operating the at least one switching element of the power supply device at the first operating frequency in response to the load of the electronic device being a second value; and operating the at least one switching element of the power supply device at the second operating frequency greater than the first operating frequency in response to the of the electronic device being a first value less than the second value.
20 . The method of claim 16 , further comprising: decreasing, via the controller, the slew rate of the at least one switching element in response to the EMI having the first EMI frequency exceeding the predetermined EMI level; and increasing, via the controller, the slew rate of the at least one switching element in response to the EMI having the second EMI frequency exceeding the predetermined EMI level, wherein EMI caused by the at least one switching element having the first EMI frequency is generated when the power supply device operates at the first operating frequency, and the EMI having the second EMI frequency greater than the first EMI frequency is generated when the power supply device operates at the second operating frequency greater than the first operating frequency.
21 . The method of claim 16 , further comprising
a load acquiring unit configured to acquire at least one of a voltage of an input power and a current of the input power; and/or at least one of a voltage of the at least one switching element and a current of the at least one switching element,
wherein the controller is configured to determine the load of the electronic device based on the acquired voltage and/or current of the input power, and/or determine the load of the electronic device based on the acquired voltage and/or current of the at least one switching element.