12V Automotive LED Driver IC TLD1114-1EP LITIX™ Basic+ Application Circuit without MOSFET

Open online SPICE simulator circuit link: atv_12v_LED_lighting_driver_TLD1114-1EP_no_mosfet_V2.tsc

12V Automotive LED Driver IC TLD1114-1EP LITIX™ Basic+
Application Circuit without power shift MOSFET

The LITIX™ Basic+ TLD1114-1EP is a single channel high-side driver IC with integrated
output stage. It is designed to control LEDs with a current up to 360 mA. In typical automotive
applications the device is capable of driving 3 red LEDs with a current up to 180 mA and even
above, if not limited by the overall system thermal properties. Practically, the output current is
controlled by an external resistor or reference source, independently from load and supply
voltage changes.

In certain applications areas, the usage of the LITIX™ Basic+ power shift feature is feasible
without external MOSFET.
This setup is configured with the load connected to OUTH and CFG=GND and shows:
1. the power shift feature without external MOSFET control but use of power resistor RD only
2. turn-ON/OFF via PWMI pin

The device starts-up by ramping-up the supply voltage VS from 0V to 16V in 1ms to show the
Power Shift feature. The output current is set at 260mA. The amount of current through the
power shift circuit is determined by a proper dimension of the RD resistor. As there is always a
path from the battery pin to the LEDs independent of the TLD1114-1EP state, the TLD1114-1EP
has no possibility to disconnect the LED from the supply line. Control of the LED state has to be
done directly by the module supplying the LED driver.

For more information related to Power Shift feature, please consult section 5.2 from datasheet
and the Power Shift feature of TLD1114-1EP application note.

A PWM pulse applied on PWMI input between 1.5ms and 1.7ms deactivates the device.

The Ambient temperature of the entire chip can be set from VTAMB voltage source.
Junction temperature can be monitored on TJ output pin.
TJ is always TAMB + temperature due to self-heating of the device considering
the main sources of power dissipation (power device, logic, internal regulator).

Thermal model description:
THERMAL_MODEL=1: P=1W; T=85°C; PCB type: 1s0p 300mm2
THERMAL_MODEL=2: P=1W; T=85°C; PCB type: 1s0p 600mm2
THERMAL_MODEL=3: P=1W; T=85°C; PCB type: 1s0p footprint
THERMAL_MODEL=4: P=1W; T=85°C; PCB type: 2s2p
where: P=power injected in chip; T=ambient temperature

Observations:
1. It is required to let the TJ pin open (no external connection)
2. The convention is 1V=1°C

{=== How to change SPICE convergence parameters ===}

Change the convergence-speed-accuracy trade-off with "Analysis -> Analysis Parameters..."
1) How to improve Accuracy
To speed up the simulation, the TR maximum time step [s] can be adjusted (default value = 10Gs).
- high values may produce less accuracy during signal transition
- a general rule is to have the ratio between test duration (End display) and TR maximum time step
in the range of 1k to 10k
2) How to improve Convergence
The SPICE model is not guaranteed to converge in every test situation with the default simulator settings.
Increasing gradually the following analysis parameters may help achieving the convergence:
Important: exceeding indicated values may impact results accuracy.
- DC absolute current error [A] from 1n (default) to 10n
- DC absolute voltage error [V] from 1u (default) to 10u
- DC relative error [%] from 1m (default) to 10m