LM5005_06 Datasheet, PDF (1/22 Pages) –

March 2006
LM5005
High Voltage 2.5 Amp Buck Regulator
General Description
The LM5005 high voltage switching regulator features all of
the functions necessary to implement an efficient high voltage
buck regulator using a minimum of external components. This
easy to use regulator includes a 75V N-Channel buck switch
with an output current capability of 2.5 Amps. The regulator
control method is based upon current mode control utilizing
an emulated current ramp. Current mode control provides in-
herent line feed-forward, cycle-by-cycle current limiting and
ease of loop compensation. The use of an emulated control
ramp reduces noise sensitivity of the pulse-width modulation
circuit, allowing reliable control of very small duty cycles nec-
essary in high input voltage applications. The operating fre-
quency is programmable from 50kHz to 500kHz. An oscillator
synchronization pin allows multiple LM5005 regulators to self-
synchronize or to be synchronized to an external clock. Ad-
ditional protection features include: current limit, thermal
shutdown and remote shutdown capability. The device is
available in a power enhanced TSSOP-20 package featuring
an exposed die attach pad to aid thermal dissipation.
Features
■ ^{Integrated 75V, 2.5A N-Channel Buck Switch}
■ ^{Ultra-wide input voltage range from 7V to 75V}
■ ^{Internal high voltage bias regulator}
■ ^{Adjustable output voltage from 1.225V}
■ ^{1.5% feedback reference accuracy}
■ ^{Current mode control with emulated inductor current ramp}
■ ^{Single resistor oscillator frequency setting}
■ ^{Oscillator synchronization input}
■ ^{Programmable soft-start}
■ ^{Shutdown / Standby input}
■ ^{Wide bandwidth error amplifier}
■ ^{Thermal Shutdown}
Package
■ ^{TSSOP-20EP (Exposed Pad)}
Simplified Application Schematic
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