LM5157-Q1, LM51571-Q1
LM5157-Q1, LM51571-Q1
www.ti.com
SNVSBK8 – OCTOBER 2020
SNVSBK8 – OCTOBER 2020
LM5157x-Q1 2.2-MHz Wide VIN 50-V Boost/SEPIC/Flyback Converter with Dual
Random Spread Spectrum
1 Features
2 Applications
•
AEC-Q100 qualified for automotive applications
– Temperature grade 1: –40°C to +125°C TA
Suited for wide operating range for car battery
applications
– 2.9-V to 45-V input operating range
– 48-V maximum output (50-V abs max)
– Minimum boost supply voltage 1.5 V when
BIAS ≥ 2.9 V
•
Battery-powered wide input boost, SEPIC, flyback
converter
Automotive voltage stabilizer in SEPIC
Automotive start-stop application
Automotive emergency call application/backup
battery booster
High voltage LiDAR power supply
Automotive LED bias supply
Multiple-output flyback without optocoupler
Hold-up capacitor charger
•
•
•
•
•
•
•
•
•
•
– Input transient protection up to 50 V
– Minimized battery drain
•
•
Low shutdown current (IQ ≤ 2.6 µA)
Low operating current (IQ ≤ 670 µA)
Audio amplifier power supply
Piezo driver/motor driver bias supply
•
Small solution size and low cost
– Maximum switching frequency up to 2.2 MHz
– 16-pin QFN package (3 mm × 3 mm) with
wettable flanks
– Integrated error amplifier allows primary-side
regulation without optocoupler (flyback)
– Minimized undershoot during cranking (start-
stop application)
3 Description
The LM5157x-Q1 (LM5157-Q1 and LM51571-Q1)
device is a wide input range, non-synchronous boost
converter with integrated 50-V power switch.
The device can be used in boost, SEPIC, and flyback
topologies. The device can start up from a 1-cell
battery with a minimum of 2.9 V. It can operate with
the input supply voltage as low as 1.5 V if the BIAS
pin is greater than 2.9 V.
– Accurate current limit (see the Device
Comparison Table)
•
•
•
EMI mitigation
– Selectable dual random spread spectrum
– Lead-less package
Higher efficiency with low-power dissipation
– 45-mΩ RDSON switch
– Fast switching, small switching loss
Avoid AM band interference and crosstalk
– Optional clock synchronization
– Dynamically programmable wide switching
frequency from 100 kHz to 2.2 MHz
Integrated protection features
Device Information
PART NUMBER
PACKAGE(1)
BODY SIZE (NOM)
LM5157x-Q1
WQFN (16)
3.00 mm × 3.00 mm
(1) For all available packages, see the orderable addendum at
the end of the data sheet.
VLOAD
VSUPPLY
BIAS VCC
SW
UVLO
RT
FB
COMP
•
SS
PGOOD
PGND AGND MODE
– Constant current limiting over input voltage
– Selectable hiccup mode overload protection
– Programmable line UVLO
Typical SEPIC Application
– OVP protection
– Thermal shutdown
•
•
•
•
Accurate ±1% accuracy feedback reference
Adjustable soft start
PGOOD indicator
Create a custom design using the LM5157x-Q1
with the WEBENCH® Power Designer
An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications,
intellectual property matters and other important disclaimers. ADVANCE INFORMATION for preproduction products; subject to change
Copyright © 2020 Texas Instruments Incorporated
Submit Document Feedback
1
without notice.
Product Folder Links: LM5157-Q1 LM51571-Q1