Automotive LED Driver IC LITIX™ Power Flex TLD5541-1QV - test bench Soft Start, Output Current Loop & Digital Dimming

Open online SPICE simulator circuit link: atv_12v_lighting_TLD5541-1QV_testbench_SoftStart_OCL_PWMI.tsc


Soft Start, Output current loop and digital dimming -
Transient with TLD5541-1QV

This model has limitations. It does
not include the driver output stage.
That is why we need to use ideal
switches (no bootstrap simulation
possible)

The PSpice model does not show all
features of the real device to keep the
simulation time in a reasonable range.

Implemented:
- Regulation Loops
- Current Limitation on the coil
- Digital and Analog PWM
- Soft Start Behavior
- Multi-Float Switch Application

NOT implemented :
- SPI interface
- Current consumption of IC
- Thermal Network
- Fault Handling
- Fault Reporting
- External Clock Sync
- Limp Home
- Spread Spectrum
- LDO Output

The test bench shows the Soft Start feature, the output current
control via analog dimming and digital dimming (PWMI pin).
Rfb is set to 150m in order to have 1A at the output. The SET
pin has a value of 1.5V at the beginning and then is decreased
to 0.7 to see that the loop will modify the current at the output
according to analog current sense adjustment features.

When the PWMI is 0 the LSGD1&2 will become 1 and HSGD1&2
will become 0. The output current will go to 0A and the voltage
begin to decrease. The digital part inside of the model is done
in 0 -3.5V voltage domain and the PWMI must be commanded
according to this specifications.

For you individual test case, please modify the parameters in
the green configuration box on the left side.

{1. click here to set circuit parameters}
{2. click on "Run" to calculate components}
{3. click on "OK" and Simulate Transient }

{Controller Frequency [F]}
frequency:= 400k {use 200K ... 700K}

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Product info: TLD5541-1QV
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