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new products
and simplifies the design of LLC power supplies.
The FAN6248 is an ideal solution for modern, high-
performance, power supply units (PSU) where high
levels of reliability and efficiency are required in a small
space. Typical applications include server and desktop
computing , gaming, large screen LCD TV and OLED TV,
networking, telecom and LED lighting applications.
The device incorporates an advanced, mixed, SR control
methodology combining instantaneous drain voltage
detection with previous switching cycle information. The
separate 100 V rated sense inputs accurately sense the
drain and source voltages across the two SR MOSFETs,
allowing for any asymmetries or poor coupling in the
secondary winding. With this advanced control approach,
the FAN6248 prevents current inversion and avoids SR
mis-triggering due to capacitive current spikes, giving
highly reliable operation. The anti-shoot-through control
within the controller enhances the reliability of the PSU
and prevents potentially destructive simultaneous turn on
of the two SR MOSFETs.
The FAN6248 and just two external resistors and
MOSFETs delivers a simple LLC converters supporting
up to 800 W. In particularly noisy environments, adding
two capacitors further enhances system stability. The
FAN6248 operates reliably and efficiently across a wide
range of power levels. Above resonance operation is
achieved without the introduction of voltage spikes. At
no load, the FAN6248 enters green mode and disables
itself. During light load conditions, the controller pulses
within green mode giving very efficient power delivery as
required by efficiency standards such as 80 PLUS®, DoE
VI, and CoC Tier 2.
Inbuilt adaptive parasitic inductance compensation also
minimizes body diode conduction in the SR MOSFETs
due to its package’s stray inductance, thereby increasing
PSU efficiency. There are four devices within the series;
power supply designers are able to select the most
appropriate for their application based upon switching
frequency (either 25 kHz-70 kHz or 60 kHz-700 kHz)
and the level of stray inductance associated with the
MOSFET. The range is suitable for use with MOSFETs
in TO-220, D2PAK, DPAK or PQFN package styles.
Furthermore, the 10.5 V high gate drive output from the
FAN6248 ensures the ability to drive these very wide
range of MOSFETs.
“The FAN6248 comprehensively addresses the needs
of modern LLC PSU designers. Innovations such as
the mixed control methodology and adaptive parasitic
inductance compensation ensure reliable and highly
efficient operation.” said Shane Chilton, General Manager
of the Power Conversion Solutions at ON Semiconductor.
“With only two resistors and MOSFETs required to realize
an advanced state-of-the-art LLC converter the controller
will prove popular with all engineers that are designing
for applications that require high levels of performance.”
Design support is available from ON Semiconductor,
including a 240 W evaluation board incorporating a
complete LLC design. A daughter board is also available
to incorporate the FAN6248 into existing designs. Please
contact your ON Semiconductor sales representative to
request evaluation boards.
Sensors from TT Electronics offer accuracy
and longevity for critical applications
TTElectronics, a global provider of engineered electronics
for performance critical applications, today launched
the PHS family of rotary position sensors that provide
precision sensing in harsh environments and in critical
applications where repair costs would be be high in the
case of a failure. The hollow shaft single turn position
sensors have been designed and built to embrace three
main design points; precision, robustness and reliability.
The rotary sensors comprise three separate series named
PHS04, PHS07 and PHS11. They convert angular
mechanical position or the motion of a shaft or axle to an
analogue or digital electrical signal and are designed for
applications that require adjustments to control variable
outputs such as position, speed or volume.
New-Tech Magazine Europe l 77