US 11,694,641 B2
Systems and methods for increasing a pulse width modulation frequency while preserving resolution
Behzad Mohtashemi, Los Gatos, CA (US); Mohammad J Navabi-Shirazi, Phoenix, AZ (US); Feng Guo, Santa Clara, CA (US); Omar Alnaggar, Palo Alto, CA (US); Venkataraman V Iyer, Sunnyvale, CA (US); Jingdong Chen, San Jose, CA (US); Yang Zhang, Saratoga, CA (US); Ming Gu, San Jose, CA (US); and Asif Hussain, Clearwater, FL (US)
Assigned to Apple Inc., Cupertino, CA (US)
Filed by Apple Inc., Cupertino, CA (US)
Filed on Jul. 21, 2022, as Appl. No. 17/870,576.
Claims priority of provisional application 63/248,316, filed on Sep. 24, 2021.
Prior Publication US 2023/0100812 A1, Mar. 30, 2023
Int. Cl. G09G 3/34 (2006.01)
CPC G09G 3/3406 (2013.01) [G09G 2310/08 (2013.01); G09G 2320/064 (2013.01)] 21 Claims
OG exemplary drawing
 
9. A method comprising:
receiving a brightness code having a bit depth corresponding to a baseline resolution for a pulse width modulation system using a first counter clock frequency and a first pulse width modulation (PWM) clock frequency;
dividing the brightness code by a value M using division circuitry to obtain a divided brightness code, wherein the value M is a positive integer;
adding a remainder of the division to the divided brightness code;
comparing the divided brightness code to a count of a counter clock having the first counter clock frequency over a first PWM clock having a second PWM clock frequency equal to the value M times the first PWM clock frequency; and
providing a pulse width modulation PWM signal to cause a light emitting element to emit light during the first PWM clock while the count is lower than the divided brightness code.