SLUUCT0B May 2023 – August 2025 TPS923652 , TPS923653 , TPS923654 , TPS923655
PRODUCTION DATA
Figure 5-11, Figure 5-12 show the hybrid dimming waveforms at 10%, and 20% duty cycles, respectively. Input voltage is 24V, with 15 white LEDs in series used as load. The full-scale LED current is set at 2A. The ADIM/HD pin is always low. The frequency of the input PWM signal at the PWM/EN pin is 20kHz.
Figure 5-11 Waveforms at 10% Duty Cycle,
20kHz Hybrid Dimming
Figure 5-12 Waveforms at 20% Duty Cycle,
20kHz Hybrid DimmingWhen the hybrid dimming is enabled, the LED current is regulated by the analog dimming at high brightness level (12.5% ~ 100%) and by the PWM dimming at low brightness level (0%~12.5%).
Figure 5-13 gives the test result of linearity of hybrid dimming, in comparison with the theoretical value. Input voltage is 24V, with 15 white LEDs in series used as load. The full-scale LED current is set at 2A. The frequency of the input PWM signal at the PWM/EN pin is 20kHz.
Figure 5-13 Hybrid Dimming
Linearity