Description:

The LM5157x-Q1 devices are non-synchronous boost converters with an integrated 50V, 6.5A (LM5157-Q1) or 50V, 4.33A (LM51571-Q1) power switch and a wide input range. The devices can be used in boost, SEPIC, and flyback topologies. The device can start up from a single-cell battery with a voltage of at least 2.9V. If the voltage on the BIAS pin is greater than 2.9V, the device can operate with an input supply voltage as low as 1.5V.

Features:

• AEC-Q100 qualified for automotive applications – Temperature grade 1: –40°C to +125°C TA

• Functional safety available – Documentation to aid in functional safety system design

• Wide operating voltage range for automotive battery applications

– Input voltage operating range of 2.9V to 45V

– Maximum output voltage of 48V (maximum absolute voltage of 50V)

– Minimum boost supply voltage of 1.5V when BIAS voltage is greater than or equal to 2.9V

– Input transient protection up to 50V

– Minimum battery drain

• Low shutdown current (IQ ≤ 2.6µA)

• Low operating current (IQ ≤ 700µA)

• Small solution size and low cost

– Switching frequency up to 2.2MHz (maximum)

– 16-pin QFN package (3mm × 3mm) with wettable flanks

– Integrated error amplifier supports primary-side regulation (flyback) without an optocoupler

– Minimized undershoot during startup (start-stop applications)

– Accurate current limit (see device comparison table)

• EMI mitigation

– Selectable dual random spread spectrum

– Leadless package

• Low power consumption, high efficiency

– 45mΩ RDSON switch

– Fast switching with low switching losses

• Avoid AM band interference and crosstalk

– Selectable clock synchronization

– Dynamically programmable wide switching frequency range from 100kHz to 2.2MHz

• Integrated protection features

– Constant current limit across the input voltage range

– Selectable hiccup mode overload protection

– Programmable line UVLO

– OVP protection

– Thermal shutdown protection

• Accurate ±1% accuracy feedback reference

• Adjustable soft start

• PGOOD indicator

• Create a customized design with the LM5157x-Q1 using WEBENCH® PowerDesigner

Applications:

• Battery-powered wide input boost, SEPIC, and flyback converters

• Automotive voltage stabilizer in SEPIC

• Automotive start-stop applications

• Automotive emergency call applications/backup battery booster

• High voltage LiDAR power supply

• Automotive LED bias supply

• Optocoupler-less multi-output flyback applications

• Hold-up capacitor charger

• Audio amplifier power supply

• Piezoelectric driver/motor driver bias supply