QBDW033A0B41Z Datasheet, PDF (12/17 Pages) Lineage Power Corporation – QBDW033A0B Series Power Modules; DC-DC Converters

Advanced Data Sheet
February 10, 2011
QBDW033A0B Series Power Modules; DC-DC Converters
36-75V_dc Input; 9.6-12V_dc Output; 33A Output Current
Layout Considerations
The QBDW033 power module series are low profile in
order to be used in fine pitch system card architectures. As
such, component clearance between the bottom of the
power module and the mounting board is limited. Avoid
placing copper areas on the outer layer directly underneath
the power module. Also avoid placing via interconnects
underneath the power module.
For additional layout guide-lines, refer to FLTR100V10
Data Sheet.
Through-Hole Lead-Free Soldering
Information
The RoHS-compliant, Z version, through-hole products use
the SAC (Sn/Ag/Cu) Pb-free solder and RoHS-compliant
components. The non-Z version products use lead-tin
(Pb/Sn) solder and RoHS-compliant components. Both
version modules are designed to be processed through
single or dual wave soldering machines. The pins have an
RoHS-compliant, pure tin finish that is compatible with both
Pb and Pb-free wave soldering processes. A maximum
preheat rate of 3C/s is suggested. The wave preheat
process should be such that the temperature of the power
module board is kept below 210C. For Pb solder, the
recommended pot temperature is 260C, while the Pb-free
solder pot is 270C max. Not all RoHS-compliant through-
hole products can be processed with paste-through-hole
Pb or Pb-free reflow process. If additional information is
needed, please consult with your Lineage Power
representative for more details.
Post Solder Cleaning and Drying
Considerations
Post solder cleaning is usually the final circuit-board
assembly process prior to electrical board testing. The
result of inadequate cleaning and drying can affect both the
reliability of a power module and the testability of the
finished circuit-board assembly. For guidance on
appropriate soldering, cleaning and drying procedures,
refer to Lineage Power Board Mounted Power Modules:
Soldering and Cleaning Application Note (AP01-056EPS).
PMBus
The QBDW033A0B series is equipped with a digital PMBus
interface to allow the module to be configured, and
communicate with system controllers. Detailed timing and
electrical characteristics of the PMBus can be found in the
PMB Power Management Protocol Specification, Part 1,
revision 1.1, available at http://pmbus.org. The
QBDW033A0B supports both the 100kHz and 400kHz bus
timing requirements. The QBDW033A0B is permitted to
stretch the clock, as long as it does not exceed the
maximum clock LO period of 35ms. All communication over
the QBDW033A0B device PMBus interface is required to
support the Packet Error Checking (PEC) scheme. The
PMBus master must generate the correct PEC byte for all
transactions and check the PEC byte returned by the
QBDW033A0B.
The QBDW033A0B supports a subset of the commands in
the PMBus 1.1 specification. Most all of the controller
parameters can be programmed using the PMBus and
stored as defaults for later use. All commands that require
data input or output use the linear format. The exponent of
the data words is fixed at a reasonable value for the
command and altering the exponent is not supported.
Direct format data input or output is not supported by the
QBDW033A0B. The supported commands are described in
greater detail below.
The QBDW033A0B also supports the SMBALERT
response protocol. The SMBALERT response protocol is a
mechanism by which a slave (the QBDW033A0B) can alert
the bus master that it wants to talk. The master processes
this event and simultaneously addresses all slaves on the
bus (that support the protocol) through the alert response
address. Only the slave(s) that caused the alert
acknowledges this request. The host performs a modified
receive byte operation to get the slave’s address. At this
point, the master can use the PMBus status commands to
query the slave that caused the alert. For more information
on the SMBus alert response protocol, see the System
Management Bus (SMBus) specification.
The QBDW033A0B contains non-volatile memory that is
used to store configuration settings and scale factors. The
settings programmed into the device are not automatically
saved into this non-volatile memory though. The
STORE_DEFAULT_ALL command must be used to
commit the current settings to non-volatile memory as
device defaults. The settings that are capable of being
stored in non-volatile memory are noted in their detailed
descriptions.
LINEAGE POWER
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