IGBT|Basic
About IGBT IPMs (Intelligent Power Modules)Examples of Actual IGBT IPMs: Packages
2023.09.13
Points of this article
・Actual IPMs are used as examples to describe package types, external dimensions, pin assignments, markings, and the method of mounting heat sinks.
In this article, IGBT IPM packages are explained. The IGB IPM examples used are, as in the previous article, models in the BM6437x series, which are ROHM’s 3rd-generation IGBT IPMs.
Examples of Actual IGBT IPMs: Packages
The package for the BM6437x series is HSDIP25, long pin type (suffix: -VA). The size of package, not including the pins, is 38.0 mm x 24.0 mm x 3.5 mm and it has 25 pins. Below, the external dimensions, pin assignments, markings, and heat sink mounting method are described.

External dimensions:HSDIP25(Long pin type, Suffix: -VA)
※Click on the dimension diagrams to enlarge
Pin Assignment
Below is a list of pin names and functions for pin numbers.
| Pin No. | Pin Name | Function |
|---|---|---|
| 1 | NC | Not connected (GND potential) |
| 2 | VBU | U phase floating control supply |
| 3 | VBV | V phase floating control supply |
| 4 | VBW | W phase floating control supply |
| 5 | HINU | U phase high side IGBT control |
| 6 | HINV | V phase high side IGBT control |
| 7 | HINW | W phase high side IGBT control |
| 8 | HVCC | Control supply for HVIC |
| 9 | GND | Ground (Note 1) |
| 10 | LINU | U phase low side IGBT control |
| 11 | LINV | V phase low side IGBT control |
| 12 | LINW | W phase low side IGBT control |
| 13 | LVCC | Control supply for LVIC |
| 14 | FO | Alarm output |
| 15 | CIN | Detecting of short circuit current trip voltage |
| 16 | GND | Ground (Note 1) |
| 17 | VOT | Temperature output |
| Pin No. | Pin Name | Function |
|---|---|---|
| 18 | NW | W phase low side IGBT emitter |
| 19 | NV | V phase low side IGBT emitter |
| 20 | NU | U phase low side IGBT emitter |
| 21 | W | W phase output |
| 22 | V | V phase output |
| 23 | U | U phase output |
| 24 | P | Inverter supply |
| 25 | NC | Not connected (Noet 2) |

Note 1: There are two GND pins, which are pins 9 and 16, but these are connected within the IPM, so that externally only one of the pins should be connected (it is recommended that pin 16 be connected), and the other should be left in the open state.
Note 2: There are no electrical connections within the IPM.
Markings
The positions and meanings of markings are indicated. Markings are displayed on the bottom side, which is the side opposite the heat sink.

Insulation Distance
Insulation distances (clearance and creepage) are as follows.
| Item | Clearance [mm] | Creepage [mm] |
|---|---|---|
| Between different-electrode charging pins | 2.50 | 3.00 |
| Between pins and heat sink | 1.45 | 1.50 |

Heat Sink Mounting Method
When installing an IPM to a heat sink, if screws are fastened to greater than the prescribed torque, or if one screw is fastened too tightly, stress may be applied to the chips within the IPM and the heat-dissipating ceramic, possibly culminating in destruction, cracking, or degradation.
The bottom-left figure shows the order of fastening to be used. When fastening, a torque driver is used to fasten to the prescribed torque. The temporary fastening torque fastening should be set to around 20 to 30% of the prescribed maximum torque.
Grease with good thermal conductivity should be applied uniformly, to a thickness of about 100 to 200 µm, onto the surface of the heat sink that is to be in contact with the IPM heat-dissipating surface. The grease applied should not undergo degradation within the operating temperature range, and should resist aging. Please take care to ensure that foreign matter is not intermixed at the contact surfaces of the IPM and the heat sink.
After applying the grease, it is recommended to install the IPM directly to the heat sink with screws after applying the grease. When a heat-radiation sheet is used between the IPM heat-dissipating surface and the heat sink, depending on the thickness and the elastic modulus of the sheet, stresses may be brought to bear on the chips within the IPM and the heat-dissipating ceramic, resulting in destruction, cracking, or degradation. When using a heat-radiation sheet, please perform thorough evaluations to ensure that the marked surface of the IPM does not bow outward toward the + side as indicated in the drawing on the lower right.

The following are specifications for fastening torques and external heat sink flatness.
| Item | Specifications | Unit | Conditions | ||
|---|---|---|---|---|---|
| Min | Typ | Max | |||
| Fastening torque | 0.59 | 0.69 | 0.78 | N・m | Mounting screw M3 Note 1 , recommended value 0.69 N・m |
| External heat sink flatness | -50 | – | +100 | µm | See ” External heat sink flatness measurement positions ” below |
Note 1: Flat washers (JIS B1256 recommended) are to be used with mounting screws.
In order to obtain the maximum effect of heat dissipation, the contact area must be made as great as possible, and the contact thermal resistance must be minimized. The flatness (bowing/roughness) of the external heat sink is, at the IPM mounting surface, assumed to be as shown below.

【Download Documents】 Basics of IGBTs
IGBTs are one of the typical power devices and are used in a wide range of applications including motor drives. This handbook provides a basic understanding of IGBTs, including their application scope and application picture based on their features, their structure and principle of operation, and how they compare with and use other power devices.
IGBT
Basic
-
About IGBTs
- Applications Using IGBTs
- IGBT Structure
- Principles of Operation of IGBTs
- Range of Application of IGBTs
- IGBT Features: Comparisons with MOSFETs and Bipolar Transistors
- Selective Use of Power Devices in Motor Applications
- Short Circuit Withstand Time (SCWT) of IGBTs
- IGBTs Incorporating Fast Recovery Diodes (FRDs)
- About IGBT IPMs (Intelligent Power Modules)
Application
-
IGBT IPM: Protection Functions and Operation Sequences
- Short Circuit Current Protection (SCP) Function of IGBT IPMs
- Control Power Supply Undervoltage Lockout(UVLO) Function of IGBT IPMs
- Thermal shutdown(TSD) Function of IGBT IPMs
- Analog Temperature Output(VOT)of IGBT IPMs
- Fault Output(FO)of IGBT IPMs
- Control inputs (HINU, HINV, HINW, LINU, LINV, LINW)of IGBT IPMs
- Protection Functions and Operation Sequences -Summary-
Product Information
