Renesas Technology Releases LFPAK -i Top-Surface-Radiation Type Package for
Power MOSFETs as New Package Offering 40% Reduction in Mounted Thermal
Offering higher thermal radiation characteristics and larger current enabling reduction
in size of server DC-DC power supplies, plus compatibility with SOP -8
Tokyo, June 28, 2004
Renesas Technology Corp. today announced the development of the LFPAK-i
(Loss-Free Package – inverted) top-surface-radiation type package as a new power MOSFET package
offering greatly improved thermal radiation characteristics through use of a top-mounted heat sink, together
with increased current capability, by means of a structure that emits heat from the upper surface. In the
initial phase products using the LFPAK -i, three power MOSFETs — the HAT2165N, HAT2166N, and
HAT2168N — for server DC-DC power supply voltage regulator (VR) are being released, with sample
shipments scheduled to begin in July 2004 in Japan.
Features of the new package are summarized below.
(1) Approximately 30% increase in current capacity through 40% reduction in mounted thermal radiation
resistance value compared with previous Renesas Technology packages
The LFPAK-i uses a structure in which the heat-radiating die header is exposed on the upper surface of
the package, and when a heat sink is mounted on top (when using forced-air cooling), the mounted
thermal resistance value in the thermal saturation state is reduced by 40%, from 25ºC/W to 15ºC/W,
compared with Renesas Technology’s current LFPAK package using a structure whereby heat is
dissipated into the printed wiring board. This enables an approximately 30% increase in current to be
achieved compared with the LFPAK, allowing server VRs to be made smaller.
(2) SOP-8 compatibility
The LFPAK-i has the same electrode arrangement and footprint as the industry-standard SOP-8
package, enabling the same kind of system design and mounting to be used as for the SOP-8.
< Product Background >
A VR that supplies power to a server’s CPU and memory converts a 12 V input voltage to the lower
voltage, typically 1.3 V, required by the CPU and memory. With the increased high current associated with
faster CPUs and memory and the lower voltages associated with miniaturization, the relevant voltage and
current are predicted to change from approximately 1.3 V and 70 A at present to 0.8 V and 150 A in the
future. In order to handle such a low voltage and high current, high-current capability is also desired of the
power MOSFETs installed in a VR to perform current control.