Ershad Ahmed

US Patent:

20060227861, Oct 12, 2006

Filed:

Feb 22, 2006

Appl. No.:

11/360462

Inventors:

Dragan Maksimovic - Boulder CO, US
Asif Syed - Boulder CO, US
Ershad Ahmed - Richardson TX, US

International Classification:

H03K 7/08
H03K 9/08

US Classification:

375238000

Abstract:

A digital pulse-width modulator is provided that receives a digital command input signal and a secondary control input signal and provides a pulse-width-modulated output signal. The pulse-width-modulated output signal comprises a pulse-width that corresponds to an integer number of slots each having a time duration. The integer number of slots corresponds to a value of the digital command signal, and the time duration is determined based upon the secondary control input signal. In one embodiment, the digital pulse-width-modulator comprises a plurality of delay cells arranged in series for propagating a clock signal through the plurality of delay cells. A time delay for each of the delay cells is determined by the secondary control input signal. A controller is enabled to set the output signal to a first value at the start of a propagation of the clock through the plurality of delay cells and to set the output signal to a second value when the clock signal propagates to one of the delay cells identified by the digital command signal. In another embodiment, the digital pulse-width-modulator is used with a switched-mode power converter. A digital command signal based on a feedback signal from the converter and a secondary control signal derived from an input voltage of the converter are received by the digital pulse-width-modulator. The digital pulse-width-modulator provides a pulse-width-modulated output signal based on the digital command signal and the secondary control signal. The output signal is then provided to the converter to control at least one switch of the converter.

US Patent:

20180175734, Jun 21, 2018

Filed:

Sep 28, 2017

Appl. No.:

15/718572

Inventors:

- London, GB
Amit Bavisi - Los Gatos CA, US
Ershad Ahmed - San Jose CA, US
Narendra Nath Gaddam - Kattangoor, IN
Vineet Tiwari - San Jose CA, US

International Classification:

H02M 3/158

Abstract:

A method and a circuit of operating a multi-phase switching converter is presented. The circuit contains a plurality of phase circuits. The method includes setting an adaptive voltage positioning parameter of an adaptive voltage positioning controller and controlling an output voltage of the multi-phase switching converter using the adaptive voltage positioning controller. The method further includes generating a threshold voltage value based on the adaptive voltage positioning parameter, comparing the output voltage of the multi-phase switching converter with the threshold voltage value and performing at least one of enabling and disabling a phase circuit based on the comparison.