1 Features
• AEC-Q100 qualified for automotive applications:
– Device temperature grade 1: –40°C to +125°C
ambient operating temperature
• Functional Safety-Capable
– Documentation available to aid functional safety
system design
• Versatile synchronous buck DC/DC controller
– Wide input voltage range of 3.5 V to 42 V
– 1% accurate, fixed 3.3-V, 5-V, or adjustable
outputs from 0.6 V to 36 V
– 150°C maximum junction temperature
– 3.3-μA typical shutdown mode current
– 15-μA typical no-load standby current
• Two interleaved synchronous buck channels
– Dual channel or single-output multiphase
– 65-ns tON(min) for high VIN/VOUT ratio
– 60-ns tOFF(min) for low dropout
• Inherent protection features for robust design
– Hiccup mode overcurrent protection
– Independent ENABLE and PGOOD functions
– Adjustable output voltage soft start
– VCC, VDDA, and gate-drive UVLO protection
– Thermal shutdown protection with hysteresis
• Optimized for CISPR 25 class 5 EMI requirements
– Slew-rate controlled adaptive gate drivers
– Spread spectrum reduces peak emissions
• 100-kHz to 2.2-MHz switching frequency
– SYNC in and SYNC out capability
– Selectable diode emulation or FPWM modes
• VQFN-40 package with wettable flank pins
• Create a custom design using the LM25143-Q1
with WEBENCH® Power Designer

2 Applications
• Automotive electronic systems
• Infotainment systems, instrument clusters
• Advanced driver assistance systems (ADAS)
• Body electronics and lighting

3 Description
The LM25143-Q1 is a 42-V DC/DC synchronous
buck controller for high-current single or dual outputs.
Deriving from a family of wide-VIN range controllers,
the device uses an interleaved, stackable, peak
current-mode control architecture for easy loop
compensation, fast transient response, excellent load
and line regulation, and accurate current sharing with
paralleled phases for higher output current. A highside
switch minimum on time of 65 ns provides large
step-down ratios, enabling the direct conversion from
12-V or 24-V automotive inputs to low-voltage rails for
reduced system complexity and cost. The LM25143-
Q1 continues to operate during input voltage dips as
low as 3.5 V, at nearly 100% duty cycle if needed.
The 15-μA no-load quiescent current with the
output voltage in regulation extends operating runtime
in battery-powered automotive systems. Power
the LM25143-Q1 from the output of the switching
regulator or another available source for even lower
input quiescent current and power loss.