12 V Automotive LED synchronous H-Bridge topology with LITIX™ Power controller TLD5191ES (Soft start, analog and digital dimming)

Open online SPICE simulator circuit link: atv_12v_LED_lighting_full-bridge_controller_TLD5191ES_SOFT_START_DIMMING.tsc

12 V Automotive LED synchronous H-Bridge topology with LITIX™ Power controller TLD5191ES
Application Circuit: Soft Start, Analog and Digital Dimming - transient

- Change simulation time:
"Analysis->Transient: Start - End Display"
- Double click on the green window to enter design criteria
- Click on "Run" and Simulate Transient

This test bench shows soft start, output current control analog dimming via SET pin and digital dimming direct control via PWMI pin.
During rising edge of SOFT_START, the internal PWM signal is extended until one of the two following conditions is reached:
- VSOFT_START exceeds VSOFT_START_LOFF
- VFBH-FBL exceeds VFBH_FBL_OL
SOFT_START and COMP capacitor values are chosen in order to see the impact of SOFT_START in the start-up until the circuit is
reaching steady-state.
If COMP ramp is faster than SOFT_START ramp and exceeds SOFT_START by more than 0.7 V, then COMP ramp will be limited
by SOFT_START.
RFB is set to 150 mOhm in order to have 1 A at the output. SET pin is decreased from 1.4 V (100% analog dimming) to 0.8 V
(50% analog dimming).

Notes:
BODY_DIODE is not a real diode but a Voltage Controlled Current Source which models the threshold and ON/OFF states
resistance.
For correct functioning of the controller, the simulation maximum time step cannot exceed 150ns. Values above this limit
affect the internal clock generation.