EP5368QI Datasheet, PDF (7/12 Pages) Enpirion, Inc. – 600mA Synchronous Buck Regulator With Integrated Inductor

April 2008
Functional Overview
The EP5368QI is a complete DCDC converter
solution requiring only two low cost MLCC
capacitors.
MOSFET switches, PWM
controller, Gate-drive, compensation, and
inductor are integrated into the tiny 3mm x
3mm x 1.1mm package to provide the smallest
footprint possible while maintaining high
efficiency, low ripple, and high performance.
The converter uses voltage mode control to
provide the simplest implementation and high
noise immunity. The device operates at a
4MHz switching frequency. The high switching
frequency allows for a wide control loop
bandwidth providing excellent transient
performance. The high switching frequency
further enables the use of very small
components making possible this
unprecedented level of integration.
Enpirion’s proprietary power MOSFET
technology provides very low switching loss at
frequencies of 4 MHz and higher, allowing for
the use of very small internal components, and
high performance. Integration of the magnetics
virtually eliminates the design/layout issues
normally associated with switch-mode DCDC
converters. All of this enables much easier
and faster incorporation into various
applications to meet demanding EMI
requirements.
Output voltage is chosen from seven preset
values via a three pin VID voltage select
scheme. An external divider option enables
the selection of any voltage in V_IN to 0.6V
range. This reduces the number of
components that must be qualified and
reduces inventory burden. The VID pins can
be toggled on the fly to implement glitch free
dynamic voltage scaling.
Protection features include under-voltage lock-
out (UVLO), over-current protection (OCP),
short circuit protection, and thermal overload
protection.
EP5368QI
Integrated Inductor
Enpirion has introduced the world’s first
product family featuring integrated inductors.
The EP5368QI utilizes a proprietary low loss
integrated inductor. The use of an internal
inductor localizes the noises associated with
the output loop currents. The inherent shielding
and compact construction of the integrated
inductor reduces the radiated noise that
couples into the traces of the circuit board.
Further, the package layout is optimized to
reduce the electrical path length for the AC
ripple currents that are a major source of
radiated emissions from DCDC converters.
The integrated inductor significantly reduces
parasitic effects that can harm loop stability,
and makes layout very simple.
Stable Over Wide Range of Operating
Conditions
The EP5368QI utilizes an internal type III
compensation network and is designed to
provide a high degree of stability over a wide
range of operating conditions. The device
operates over the entire input and output
voltage range with no external modifications
required. The very high switching frequency
allows for a very wide control loop bandwidth.
Soft Start
Internal soft start circuits limit in-rush current
when the device starts up from a power down
condition or when the “ENABLE” pin is
asserted “high”. Digital control circuitry limits
the V_OUT ramp rate to levels that are safe for
the Power MOSFETS and the integrated
inductor. The soft start ramp rate is nominally
1.5V/mS.
©Enpirion 2008 all rights reserved, E&OE
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