1 Features

? AEC-Q100 qualified for automotive applications

– Grade 1: –40°C to 125°C ambient operating

temperature

– Device HBM classification level H1C

– Device CDM classification level C5

? Input voltage range: 5.5 V to 36 V

– Operation down to 5.15 V after start-up

? Up to 3-A continuous with 4 accuracy

? Adaptive on-time current control

– Low offset high-side current sense amplifier

– Stable with any combination of ceramic, and

aluminum capacitors

? Programmable switching frequency from 100 kHz

to 2.2 MHz

? Advanced dimming operation

– 1000:1 precision PWM dimming

– 15:1 precision analog dimming

– 1.4-kHz internal analog input to PWM duty

cycle translation

? Cycle-by-cycle switch overcurrent protection

? Open-drain fault indicator output

– LED short circuit, open circuit and cable

harness fault indication

? Thermal shutdown protection

2 Applications

? Headlight

? Front fog light LED driver module

3 Description

The TPS92643-Q1 is a monolithic, synchronous Buck

LED driver with a wide 5.5-V to 36-V operating

input voltage range and 40-V tolerance that supports

load dump for duration of 400 ms. The TPS92643-

Q1 implements an adaptive on-time average current

mode control based on inductor valley current

detection. The adaptive on-time control provides

near constant switching frequency that can be set

between 100 kHz and 2.2 MHz. Inductor current

sensing and closed-loop feedback enables better than

±4 accuracy over wide input, output and ambient

temperature.

The high-performance LED driver can independently

modulate LED current using both analog or PWM

dimming techniques. Linear analog dimming range

with over 15:1 range is obtained by setting the IADJ

voltage. PWM dimming of LED current is achieved by

directly modulating the UDIM input pin with desired

duty cycle or setting the analog voltage at APWM

to enable internal analog-to-PWM conversion. The

internal PWM generator translates the external analog

voltage by comparing it to an internal 1.4-kHz ramp

signal.

The TPS92643-Q1 incorporates advanced diagnostic

and fault protection featuring: cycle-by-cycle switch

current limit, bootstrap undervoltage, LED open, LED

short and thermal shutdown.

The TPS92643-Q1 is available in a 6.6-mm × 5.1-mm

thermally-enhanced 16-pin HTSSOP package with

0.65-mm lead pitch.