EP5352Q Datasheet, PDF (7/16 Pages) Enpirion, Inc. – 500/600/800mA Synchronous Buck Regulators With Integrated Inductor

Detailed Description
Functional Overview
The EP53x2Q family 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 5mm x
4mm x 1.1mm package to provide the smallest
footprint possible while maintaining high
efficiency and high performance. The converter
uses voltage mode control to provide the
simplest implementation and high noise
immunity. The device operates at a 4 MHz
switching frequency. The high switching
frequency allows for a wide control loop
bandwidth providing excellent transient
performance. The 4 MHz switching frequency
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
very wide control loop bandwidth. Unique
magnetic design allows for integration of the
inductor into the very low profile 1.1mm
package. Integration of the inductor virtually
eliminates the design/layout issues normally
associated with switch-mode DCDC
converters. All of this enables much easier
and faster integration into various applications
to meet demanding EMI requirements.
EP5382Q/EP5362Q/EP5352Q
Protection features include under-voltage lock-
out (UVLO), over-current protection (OCP),
short circuit protection, and thermal overload
protection.
Integrated Inductor
Enpirion has introduced the world’s first
product family featuring integrated inductors.
The EP53x2Q family utilizes a low loss, planar
construction 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.
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
3.3mV/μSec.
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 the 0.6 to V_IN -
V_dropout. This reduces the number of
components that must be qualified and
reduces inventory problems. The VID pins can
be toggled on the fly to implement glitch free
dynamic voltage scaling.
Over Current/Short Circuit Protection
The current limit function is achieved by
sensing the current flowing through a sense P-
MOSFET which is compared to a reference
current. When this level is exceeded the P-
FET is turned off and the N-FET is turned on,
pulling V_OUT low. This condition is maintained
for a period of 1mS and then a normal soft start
is initiated. If the over current condition still
persists, this cycle will repeat in a “hiccup”
mode.
©Enpirion 2009 all rights reserved, E&OE
03132
7
4/28/2009
www.enpirion.com
Rev:B