To better meet the stringent requirements of today's automobile industry, our ACEPACK™ SMIT and HU3PAK surface-mount packages with top-side cooling ensure higher power density and improved thermal management for very efficient and more compact systems.

As the performance of a semiconductor device depends on its temperature, how it behaves can vary substantially depending on its package's construction and how it's mounted on a circuit board (PCB). To ensure a chip's performance complies with its specifications and to avoid failure, it is very important to correctly manage the transfer of heat between the chip and its environment.

This is why ST's ACEPACK SMIT and HU3PAK SMD packages with top-side cooling are ideal for high-performance automotive and industrial applications.

Compared to standard surface-mount packages, power modules in SMD packages with top-side cooling offer a smaller form factor, better thermal performance and higher design flexibility.

In packages with top-side cooling, the semiconductor chip is connected to a direct bonded copper (DBC) ceramic substrate on the top side of the package. This means that the power module, which is directly mounted on the surface of the circuit board (PCB), can be directly connected to an external heatsink in order to ensure the maximum power dissipation and optimize thermal performance.

Moreover, this enables the PCB-module-heat sink stack to be automatically assembled, ensuring a lower profile and more cost-effective production.

All automotive-grade HU3PAK packages are AEC-Q101 qualified, while ACEPACK SMIT packages are both AQG 324 and AEC-Q101 qualified depending on the internal dice configuration.

Key features

  • Small PCB footprint and lower PCB temperature
  • Scalable Product offering including Discrete and Module
  • Single heatsink for all Power Device
  • Low profile Power device
  • Top-side cooling with Low junction to case thermal resistance
  • High creepage distance
  • AEC-Q101 and AQG-324 qualified
top side cooling packages
acepack smit topologies

60 A 1200 V thyristor controlled half bridge in ACEPACK SMIT module

Automotive 600 V, 60 A Ultrafast Bridge Module

Automotive-grade N-channel 650 V, 35 mOhm typ., 64 A MDmesh

Automotive-grade N-channel 650 V, 89 mOhm typ., 32 A MDmesh


30 A 1200 V automotive grade SCR Thyristor in HU3PAK package

Automotive-grade N-channel 650 V, 83 mOhm typ., 37 A MDmesh in HU3PAK

Automotive-grade silicon carbide Power MOSFET 650 V, 58 mOhm typ., 30 A in an HU3PAK package

Application examples

on-board chargers On-board chargers
ev charging stations EV charging stations
uninterruptible power supplies Uninterruptible power supplies
renewable energy inverters Renewable energy inverters

ACEPACK SMIT power modules with top-side cooling

acepack smit power modulesACEPACK SMIT power modules feature a direct bonded copper (DBC) ceramic substrate that enables various electrical circuit solutions from single-switch to multi-die topologies in the 1 to 50 kW power range. Its epoxy molding compound offers outstanding resistance to moisture and heat for automotive and industrial applications. With its low thermal resistance, low electrical parasitic inductance and outstanding resistance to moisture, ACEPACK SMIT power modules are ideal for industrial and automotive applications.

With AEC-Q101 qualified solutions for blocking voltages up to 1200 V, our STPOWER ACEPACK SMIT power modules are ideal for hybrid/EV traction inverters, on-board chargers and charging stations.

For 1200 V blocking voltages, we recommend an AC-DC module embedding two STTN6050H-12M1Y SCR modules and five half-bridge SH16M12W3AG SiC MOSFETs on the primary.

For applications requiring a 400 V blocking voltage, we recommend an AC-DC module embedding two STTN6050H-12M1Y SCR modules and three half-bridge STGSH80HB65DAG IGBTs for the PFC plus two half-bridge SH68N65DM6AG or SH32N65DM6AG SJ MOSFETs for the LLC depending on the required power level and one STTH60RQ06-M2Y fast rectifier for output rectification.

HU3PAK power modules with top-side cooling

d3pak hu3pak

Designed to be surface mounted on a printed circuit board, HU3PAK packages with top-side cooling make it possible to connect a heatsink to the power module and avoid having to dissipate the heat through the PCB as with D3PAK or H2PAK/D2PAK packages.

In addition to optimizing thermal performance and allowing the maximum power possible to go through the device, the HU3PAK offers a 10% smaller PCB footprint and is 30% thinner (with a height below 3.6 mm compared to the D3PAK), and reduces thermal resistance by 20% and the junction temperature by 17% with respect to H2PAK/D2PAK packages (when benchmarked on a 3kW FB LLC board).

Perfect for stationary and automotive battery chargers including on-board chargers, designers can use our 1200V SCR Thyristor (TN3050H-12L2Y) and our 3rd generation silicon-carbide Power MOSFET (SCT070HU120G3AG), both available in a HU3PAK package.

A wide range of N-channel super-junction MOSFETs in an HU3PAK package are also available for your designs:

d3pak versus hu3pak

Recommended resources

acepack smit

New molded module for industrial power applications

PDF HU3PAK package mounting and thermal behavior

HU3PAK module package guidelines for mounting and thermal management

PDF acepack smit module package guidelines

ACEPACK SMIT module package guidelines for mounting and thermal management

silicon controlled rectifiers for ev charging applications

In this one-hour on-demand webinar, we will show you an innovative solution that uses a silicon-controlled rectifier (SCR) to replace the electromechanical relay and NTC. In addition to providing a smaller footprint and thinner design, this solution offers improved control of the inrush current, faster charging times and a longer lifespan in harsh (heat, vibrations, etc.) automotive conditions typically encountered by on-board chargers.

We also highlight our innovative automotive-grade ACEPACK™ SMIT and HU3PAK surface-mount (SMD) packages with top-side cooling designed to ensure higher power density and improved thermal management for very efficient and more compact systems.

Our new series of AEC-Q101-qualified Thyristors (SCRs) will also be presented and their performance actually measured in an AC or DC power conversion circuit.