Integrated Digital POL Power-Management System ... - Power-One

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LEAPFROG: INDUSTRY FIRST
AN ELECTRONIC DESIGN EXCLUSIVE
Roger Allan /// TECHNOLOGY EDITOR
INTEGRATED DIGITAL POL
POWER-MANAGEMENT SYSTEM
SIMPLIFIES DESIGN, CUTS COSTS
Thanks to an innovative architecture, this system
enables 32 POL converters to communicate effectively
under the guidance of a single system controller.
Power systems are becoming more complex. To
satisfy different circuit power-supply voltage
and current needs, more and more point-ofload
(POL) regulators and dc-dc converters are
crowding pc boards—to the point where
they’re becoming unmanageable. The problem
is threefold: the amount of pc-board space
being absorbed, the number of external components
required, and the lack of coordination
between the horde of POL converters.
By investing considerable resources to develop
a digital silicon-based architecture, its Z-
One architecture, Power One came up with a
unique system that fully integrates a power
system’s management functions with those of
the power-conversion circuitry. What results is
a solution that cuts overall system-level costs
by some 20% to 50% compared to existing
approaches and allows an industry-record 32
48 V
POL converters to fully communicate with
each other under the command of a single system
controller (Fig. 1).
According to Power One, this is the most
capable power-management system by far. The
nearest competitor, it claims, offers only 12
POL converters with limited functionality and
the need for external tracking field-effect transistors
(FETs).
Central to Power One’s Z-One system shown in Figure 1
is the company’s single-wire Z-One digital bus. The highspeed
bidirectional bus provides both frequency synchronization
and data transfer and can access all POL converters
in a single communication cycle. It carries all the
information to and from the POL converters and the Power
Digital Manager (PDM), including all parameters for
each POL converter, such as the output voltage, sequencing,
tracking, monitoring, interleaving, protection thresholds,
feedback loop configuration, and fault-management
information. The digital POL converters can operate with
a wide input voltage range from 3 to 13 V.
I 2 C bus
ZIOS graphical
user interface
••• 50 •••
DC-DC front end
Z-series Power
Digital Manager
3 to
13.2 V
Z-One digital bus
Host system
Up to 32 Z-POLs
1. Up to 32 POL converters can be fully programmed and managed from a
single digital Power Digital Manager using this intelligent Z-One series
architecture from Power One. The architecture integrates control, powerconversion,
and communications functions under one entity.
V OUT
The Z-One system integrates two ASICs, the ZM7100
PDM, and the maXyz ZY7000 series of POL converters.
Both are based on Power One’s custom silicon.
The ZM7100 PDM is a centralized system manager
that programs and controls sequencing, tracking, supply
supervision, and intelligence for the analog-to-digital
converters (ADCs) with margining, reset, and environmental-monitoring
capabilities (Fig. 2). The Z-series nonisolated
POL converters receive commands from the
ZM7100 PDM that change the settings but also communicate
their status back to the controller. Everything can
be controlled by Power One’s Z-series Intelligent Operating
System (ZIOS), which features a graphical-user inter-
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●●● INDUSTRY FIRST / POL POWER-MANAGEMENT SYSTEM
2. Two ASICs are fundamental to the Z series architecture:
the Z7100 PDM (left) and the ZY7000 series POL converter
(right).
face (GUI). Engineers can easily configure
and simulate power architectures
during system design. To add
more flexibility and control to the
system, users can program the
ZM7100 controller through an
industry-standard I 2 C interface.
The ZM7100 can program and
manage up to 32 POL converters. It
continuously monitors their output
voltages, currents, and temperatures.
In addition, it monitors the intermediate
bus voltage, accepts external
programmable interrupts, initiates
crowbar protection, and controls dcdc
front ends, including those not
manufactured by Power One.
In developing this new powermanagement
system, Power One created
several key pieces of intellectual
property. A significant number of
patents related to the implementa-
tion of the overall system’s architecture,
including control and configuration,
as well as patents in the
design and implementation of the
digital pulse-width-modulated
(PWM) controller have been filed.
The first POL converter to be
available is the 20-A ZY7120 with
an input between 3 and 13 V dc and
a programmable output of 0.5 to 5.5
V dc within a tolerance of 1%. The
5-A ZY7105 and the 10-A ZY7110
POL converters and ZX7000 series
power blocks are planned series
expansions.
Each POL converter features current
sharing and active control of the
low-side FET for turn-on with 100%
pre-biased outputs. The 20-A converters
come in surface-mount packages
for either vertical or horizontal
mounting, with respective dimen-
4. Using Power One’s ZIOS GUI, various system configurations can be set up on
a host computer display for programming parameters and monitoring the activities
of POL converters.
••• 52 •••
3. Power One’s highly programmable POL converters are
available in surface-mount packages for either horizontal or
vertical (shown) mounting.
sions of 1.25 by 0.3 by 0.55 in. and
1.25 by 0.63 by 0.3 in. (Fig. 3).
The converters use digital PWM
control. The 20-A products can handle
current densities of up to 52
A/in. 2 They can also be used as
standalone components without the
ZM7100 controller, via default
tracking, sequencing, and protection
settings, as well as resistor outputvoltage
programming, or a standard
VID code.
GUI PROVIDES FLEXIBILITY • Power
One’s ZIOS GUI, along with its GUI
development tool, provides a comprehensive
set of management and
design capabilities for a power-management
system, including output
tracking and sequencing, POL-converter
frequency synchronization and
interleaving, and the setting of
thresholds for overvoltage, undervoltage,
and overcurrent protections.
Four independent OK signal lines are
available for comprehensive fault
management.
Various system configuration windows
can be set up for programming
and viewing a host of power-system
activities. For example, ZY7000
POL converters can be set up in
groups to accelerate the programming
process (Fig. 4).
Pricing for the ZM7100 DPM controller
is $12 to $15, and the 20-A
POL converter is expected to cost
$16 to $20, in prototype quantities.
Availability is expected in the third
quarter. ED Online 7336
Power One Corp.
www.power-one.com
(803) 987-8741
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