LM5576/LM5576Q
June 14, 2010
SIMPLE SWITCHER® 75V, 3A Step-Down Switching
Regulator
General Description
The LM5576 is an easy to use SIMPLE SWITCHER® buck
regulator which allows design engineers to design and optimize
a robust power supply using a minimum set of components.
Operating with an input voltage range of 6 - 75V, the
LM5576 delivers 3A of continuous output current with an integrated
170mΩ N-Channel MOSFET. The regulator utilizes
an Emulated Current Mode architecture which provides inherent
line regulation, tight load transient response, and ease
of loop compensation without the usual limitation of low-duty
cycles *ociated with current mode regulators. The operating
frequency is adjustable from 50kHz to 500kHz to allow
optimization of size and efficiency. To reduce EMI, a frequency
synchronization pin allows multiple IC’s from the
LM(2)557x family to self-synchronize or to synchronize to an
external clock. The LM5576 guarantees robustness with cycle-
by-cycle current limit, short-circuit protection, thermal
shut-down, and remote shut-down. The device is available in
a power enhanced TSSOP-20 package featuring an exposed
die attach pad for thermal dissipation. The LM5576 is supported
by the full suite of WEBENCH® On-Line design tools.
Features
■ LM5576Q is an Automotive Grade product that is AECQ100
grade 1 qualified (−40°C to + 125°C operating
junction temperature)
■ Integrated 75V, 170mΩ N-channel MOSFET
■ Ultra-wide input voltage range from 6V to 75V
■ Adjustable output voltage as low as 1.225V
■ 1.5% feedback reference accuracy
■ Operating frequency adjustable between 50kHz and
500kHz with single resistor
■ Master or slave frequency synchronization
■ Adjustable soft-start
■ Emulated current mode control architecture
■ Wide bandwidth error amplifier
■ Built-in protection
■ Automotive Grade product datasheet that is AEC-Q100
grade 0 qualified is available upon request.
(−40°C to + 150°C operating junction temperature)
Package
■ TSSOP-20EP (Exposed Pad)
