SNVSBY7 March 2021 TPS92390
In addition to phase-shift PWM dimming, TPS92390 supports a hybrid-dimming mode. Hybrid dimming combines PWM and current modes for brightness control for the display brightness path. By using hybrid dimming, dimming ratio could be increased by another 8 times. In hybrid mode, PWM dimming is used for low brightness range of brightness, and current dimming is used for high brightness levels as shown in Figure 7-11. Current dimming control enables improved optical efficiency due to increased LED efficiency at lower currents. PWM dimming control at low brightness levels ensures linear and accurate control. Hybrid mode can be selected through resistor value at MODE pin as Table 7-7. The PWM and current modes transition threshold can be set at 12.5% or at 0% brightness. The latter selection allows for pure current dimming control mode.