LM34919C-Q1
www.ti.com
SNVS831A –SEPTEMBER 2013–REVISED DECEMBER 2013
LM34919C-Q1 Ultra Small 50V, 600 mA Constant On-Time Buck Switching Regulator
Check for Samples: LM34919C-Q1
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FEATURES
APPLICATIONS
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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
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Automotive Safety and Infotainment
High Efficiency Point-of-Load (POL) Regulator
Telecommunication Buck Regulator
Secondary Side Post Regulator
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DESCRIPTION
No Loop Compensation Required
Ultra-Fast Transient Response
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.
Operating Frequency Remains Constant with
Load Current and Input Voltage
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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
4.5V - 50V
Input
VIN
VCC
C3
C1
C5
REN
RON
LM34919C
BST
RON
EN
VOUT
C4
L1
RPGD
PGD
VOUT
SW
PGD
SS
D1
R1
R2
R3
C2
ISEN
FB
C6
RTN
SGND
Figure 1. Basic Step Down Regulator
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PRODUCTION DATA information is current as of publication date.
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