LM34919C-Q1
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SNVS831A – SEPTEMBER 2013 – REVISED DECEMBER 2013
LM34919C-Q1 Ultra Small 50V, 600 mA Constant On-Time Buck Switching Regulator
Check for Samples: LM34919C-Q1
FEATURES
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•2 AEC-Q100 qualified (Tj = -40°C to 125°C)
• Maximum Switching Frequency: 2.6 MHz
• Input Voltage Range: 4.5 V to 50 V
• Integrated N-Channel buck switch
• Integrated Start-Up Regulator
• No Loop Compensation Required
• Ultra-Fast Transient Response
• Operating Frequency Remains Constant with
Load Current and Input Voltage
• Adjustable Output Voltage
• Power Good Output
• Enable Input
• Valley Current Limit at 0.64 A Typical
• Precision Internal Voltage Reference
• Low IQ Shutdown (<10 µA)
• Highly Efficient Operation
• Thermal Shutdown
• 12-Bump 2 mm x 2 mm DSBGA and 12-pin 4
mm x 4 mm WSON Packages
APPLICATIONS
• Automotive Safety and Infotainment
• High Efficiency Point-of-Load (POL) Regulator
• Telecommunication Buck Regulator
• Secondary Side Post Regulator
DESCRIPTION
The LM34919C Step Down Switching Regulator
features all of the functions needed to implement a
low-cost, efficient, buck bias regulator capable of
supplying 0.6 A to the load. This buck regulator
contains an N-Channel Buck Switch and is available
in DSBGA and WSON packages. The constant on-
time feedback regulation scheme requires no loop
compensation, results in fast load transient response,
and simplifies circuit implementation. The operating
frequency remains constant with line and load
variations due to the inverse relationship between the
input voltage and the on-time. The valley current limit
results in a smooth transition from constant voltage to
constant current mode when current limit is detected,
reducing the frequency and output voltage, without
the use of foldback. Additional features include:
Power Good, enable, VCC undervoltage lockout,
thermal shutdown, gate drive undervoltage lockout,
and maximum duty cycle limiter.
4.5V - 50V
Input
C1 C5
REN
RON
VOUT
RPGD
PGD
VIN VCC
LM34919C
RON
EN
BST
PGD
SW
SS ISEN
C6
FB
RTN
SGND
C3
C4
L1
D1
R1
R2
VOUT
R3
C2
Figure 1. Basic Step Down Regulator
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PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
Copyright © 2013, Texas Instruments Incorporated
