LM25148-Q1
SNVSC03 – JUNE 2021
LM25148-Q1 42-V Automotive Synchronous Buck DC/DC Controller with Ultra-Low IQ
and Dual Random Spread Spectrum
1 Features
2 Applications
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•
AEC-Q100 qualified for automotive applications:
– Device temperature grade 1: –40°C to +125°C
ambient operating temperature
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•
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Automotive electronic systems
Advanced driver assistance systems (ADAS)
Infotainment and clusters
Integrated EMI mitigation
3 Description
– Selectable dual random spread spectrum
(DRSS) feature for enhanced EMI performance
across low and high-frequency bands
– Optimized for CISPR 25 Class 5 requirements
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, 12-V, or
adjustable outputs from 0.8 V to 36 V
The LM25148-Q1 is a 42-V, ultra-low IQ synchronous
buck DC/DC controller for high-current, single-output
applications. The controller uses a peak-current-mode
control architecture for easy loop compensation,
fast transient response, and excellent load and
line regulation. The LM25148-Q1 can be set up in
interleaved mode (paralleled output) with accurate
current sharing for high-current applications. It can
operate at input voltages as low as 3.5 V, at nearly
100% duty cycle if needed.
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– 150°C maximum junction temperature
– Lossless DCR or shunt current sensing
– Shutdown mode current: 2.2 µA
– No-load standby current: 9 µA
The LM25148-Q1 has a unique EMI reduction
feature known as Dual Random Spread Spectrum
(DRSS). Combining low-frequency triangular and
high-frequency randomized modulations mitigates
EMI across lower and higher radio-frequency bands,
respectively. This hybrid technique aligns with
the multiple resolution bandwidth (RBW) settings
specified in industry-standard EMC tests.
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Switching frequency from 100 kHz to 2.2 MHz
– SYNC in and SYNC out capability
– Selectable PFM or FPWM modes
Inherent protection features for robust design
– Internal hiccup mode overcurrent protection
– ENABLE and PGOOD functions
– VCC, VDDA, and gate-drive UVLO protection
– Internal or external loop compensation
– Thermal shutdown protection with hysteresis
Create a custom design using the LM25148-Q1
with WEBENCH® Power Designer
Device Information
PART NUMBER
PACKAGE(1)
BODY SIZE (NOM)
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LM25148-Q1
VQFN (24)
3.5 mm × 5.5 mm
(1) For all available packages, see the orderable addendum at
the end of the data sheet
VIN = 3.5 V...42 V
CIN
CVCC
2.2
F
VCC
VIN
EN
CBOOT
HO
CBOOT
0.1
VOUT = 5 V
IOUT = 8 A
F
Q1
Q2
RS
CNFG
LO
5 m
PGOOD
0.56
H
CO
SW
4 ꢀ 47
F
VDDA
LO
LM25148-Q1
PGND
RFB
PFM/SYNCIN
FB
24.9 k
CS
VOUT
EXTCOMP
* Tie to GND
if not used
VCCX
RT
VDDA
AGND
RT
CVDDA
0.1
* VOUT tracks VIN if VIN < 5.2 V
F
9.52 k
Typical Application Schematic
CISPR 25 EMI Performance, 150 kHz to 30 MHz
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
without notice.