EP5358LUI/EP5358HUI
Detailed Description
Functional Overview
Integrated Inductor: Low-Noise Low-EMI
The EP5358xUI requires only 2 small MLCC
capacitors for a complete DC-DC converter
The EP5358xUI utilizes a proprietary low loss
integrated inductor. The integration of the
inductor greatly simplifies the power supply
design process. The inherent shielding and
compact construction of the integrated inductor
reduces the conducted and radiated noise that
can couple into the traces of the printed circuit
solution.
switches,
The device integrates MOSFET
PWM controller, Gate-drive,
compensation, and inductor into a tiny 3mm x
3mm x 1.1mm micro-QFN package. Advanced
package design, along with the high level of
integration, provides very low output ripple and
noise. The EP5358xUI uses voltage mode
control for high noise immunity and load
matching to advanced ≤90nm loads. A 3-pin
VID allows the user to choose from one of 8
board.
Further, the package layout is
optimized to reduce the electrical path length
for the high di/dT input AC ripple currents that
are a major source of radiated emissions from
DC-DC converters. The integrated inductor
provides the optimal solution to the complexity,
output ripple, and noise that plague low power
DCDC converter design.
output voltage settings.
The EP5358xUI
comes with two VID output voltage ranges.
The EP5358HUI provides VOUT settings from
1.8V to 3.3V, the EP5358LUI provides VID
settings from 0.8V to 1.5V, and also has an
external resistor divider option to program
output setting over the 0.6V to VIN-0.25V
range. The EP5358xUI provides the industry’s
highest power density of any 500mA DCDC
converter solution.
Control Matched to sub 90nm Loads
The EP5358xUI utilizes an integrated type III
compensation network. Voltage mode control
is inherently impedance matched to the sub
90nm process technology that is used in
today’s advanced ICs. Voltage mode control
also provides a high degree of noise immunity
at light load currents so that low ripple and high
accuracy are maintained over the entire load
range. The very high switching frequency
allows for a very wide control loop bandwidth
and hence excellent transient performance.
The key enabler of this revolutionary
integration is Enpirion’s proprietary power
MOSFET technology. The advanced MOSFET
switches are implemented in deep-submicron
CMOS to supply very low switching loss at high
switching frequencies and to allow a high level
of integration. The semiconductor process
allows seem-less integration of all switching,
control, and compensation circuitry.
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 VOUT ramp rate to levels that are safe for
the Power MOSFETS and the integrated
inductor.
The proprietary magnetics design provides
high-density/high-value magnetics in a very
small footprint.
Enpirion magnetics are
carefully matched to the control and
compensation circuitry yielding an optimal
solution with assured performance over the
entire operating range.
The EP5358HUI has a soft-start slew rate that
is twice that of the EP5358LUI.
Protection features include under-voltage lock-
out (UVLO), over-current protection (OCP),
short circuit protection, and thermal overload
protection.
Excess bulk capacitance on the output of the
device can cause an over-current condition at
startup. The maximum total capacitance on
the output, including the output filter capacitor
and bulk and decoupling capacitance, at the
load, is given as:
EP5358LUI:
©Enpirion 2009 all rights reserved, E&OE
9
www.enpirion.com
03541
5/29/2009
Rev:A
ENPIRION [ ENPIRION, INC. ]
