MA-301-27E
Heat Sink, 4.6 °C/W, TO-247, TO-264, 55.8 mm, 43.5 mm, 27 mm
- Manufacturer: OHMITE
- Product type: Natural Convection Heat Sinks
- SVHC: No SVHC (15-Jan-2018)
- Product Range: 0
- Packages Cooled: TO-247, TO-264
- Heat Sink Material: Aluminium Alloy
- Thermal Resistance: 4.6°C/W
- External Width - Metric: 0
- External Height - Metric: 0
- External Length - Metric: 27mm
- External Width - Imperial: 0
- External Diameter - Metric: -
- External Height - Imperial: 0
- External Length - Imperial: 1.06"
- External Diameter - Imperial: -
| Delivery and price | |
|---|---|
| Units per pack | 100 |
| Price | 8.03 € |
| Current stock | 10+ |
| Lead time | 30 days |
## **M Series Heatsinks Heatsink with clips for TO-264 and TO-247** ## **F e a t u r e S** - Minimum assembly cost and labor. Spring Clips make the mounting holes and fasteners obsolete in assembly operations & reduce costs. - Maximum Thermal Transfer. Maximum surface area per unit volume, efficient cooling fins & consistent mounting force reduces thermal resistance - Maximum Repeatability. Constant spring force over repeated assembly/disassembly Ohmite introduces the M series, patented (Pat. No. 7,151,669), high performance, low cost, configurable, scalable and compact heat sink with matrix clip system for TO-247 and TO-264 packages. This powerful heat sink provides the easiest assembly, largest surface area and smallest footprint. It is the ideal type of heat sink for high power density and small size (1U or 2U) electronic packaging with forced convection cooling. - Maximum Reliability. Resilient spring action locks electronic component in place. Fewer parts in assembly and no fasteners and washers required. Prevent short circuit by eliminating metal particles generated from hardware or thread tapping - Design Flexibility. Maximum flexibility for dynamic device locations and power up grading. “Configureto-Fit” & “Scale-to-Meet” options give designers the total freedom to configure the heat sink to fit their packaging designs and to scale the heat sink to meet their power dissipations. ## ~~**S e r i e S S p e C i F i C at i o n S**~~ ||||**Thermal**| |---|---|---|---| ||**Surface Area**|**Weight Resistance**|**Weight Resistance**| |**Part No.**|**(in2/mm2)**|**(oz./g)**|**(°c/w)***| |MV-102-55E†45 / 29,097|45 / 29,097|2.2 / 63|6.0| |MA-102-55E|45 / 29,097|2.2 / 63|5.2| |MV-101-27E†22 / 14,284|22 / 14,284|1.1 / 31|9.6| |MA-101-27E†22 / 14|22 / 14,284|1.1 / 31|8.0| |MV-302-55E|76 / 49,218|4.7 / 134|4.7 / 134<br>3.6| |MA-302-55E|76 / 49,218|4.7 / 134|4.7 / 134<br>3.0| |MV-301-27E 37.3 / 24,161|MV-301-27E 37.3 / 24,161|2.3 / 66|5.5| |MA-301-27E 37.3 / 24|MA-301-27E 37.3 / 24,161|2.3 / 66|4.6| * R-thetac-a for 18W dissipation total for two devices in natural convection †Discontinued ## ~~**C H a r a C t e r i S t i C S**~~ ||~~**C H a r a C t e r i S t i C S**~~| |---|---| |**Heat Sink**|Aluminum Alloy 6063-T5 or Equivalent with either degreased or black anodized| ||finish.| |**Spring Clip**|Music Wire, Per ASTM A228 with bright nickelplating| |**Solder Foot**|Cold-rolled Steel, Per ASTM A-366 with pure tin over copper strike. RoHS com-| ||pliant.| |**Interface thermal resistance**|Thermaljoint compound or 0.005 Grafoil(TGon 800 byLaird)| |**Interface electrical isolation**|Sil-Pad 900S byBergquist or equivalent| (continued) **176** 1-866-9-OHMITE • Int’l 1-847-258-0300 • Fax 1-847-574-7522 • www.ohmite.com • info@ohmite.com ## **M Series Heatsinks Heatsink with clips for TO-264 and TO-247** ## ~~**H e at D i S S i pat i o n**~~ **==> picture [516 x 407] intentionally omitted <==** **----- Start of picture text -----**<br> For two devices Air Velocity (ft./min.)<br>0 200 400 600 800 1000 1200<br>140 7<br>120 6<br>100 5<br>MA-101-27<br>80 4 MA-301-27<br>MA-102-55<br>60 3<br>MA-302-55<br>40 2<br>20 1<br>0 0<br>0 10 20 30 40 50<br>Heat Dissipated, total for two devices (watts)<br>D i M e n S i o n S<br>2.20" (55.8mm) (1.8mm) ø 0.07" CL user defined values CL 4x (1.8mm) ø 0.07" CL definedvalueuser 4x<br>Y X ø 0.10" X ø 0.10"<br>1.34" (34.1mm) (2.5mm) (2.5mm)<br>1.52" 1.71" V V<br>(38.6mm) (43.5mm) W -55E W -27E<br>Z Z<br>-102-55E -302-55E<br>-101-27E -301-27E<br>0.83" 0.84" 0.16" 0.90"<br>(21.1mm) 0.14" (21.3mm) (4.2mm) 0.08" 2.01" (51mm) 0.08" (22.9mm)<br>0.95" ±.025 (3.6mm) 1.04" ±.025 (2.0mm) 2.17" (55mm) (2.0mm) 1.06" (27mm)<br>(24.1mm) (26.4mm)<br>Part Number W V Z*<br>MV-102-55E<br>1.35" / 34.3 0.95" / 24.1 0.18" / 4.6<br>MA-102-55E *Device package<br>MA-101-27E dimensions can<br>MA-101-27E vary. Customer<br>MV-302-55E should verify<br>2.20" / 55.9 1.04" / 26.4 0.21" / 5.3<br>MA-302-55E this dimension.<br>MA-301-27E<br>MA-301-27E<br>C) °<br>to Ambient (°C/watts)<br>Case Temp. Rise above Ambient ( Thermal Resistance from Case<br>**----- End of picture text -----**<br> ## ~~**H o w t o o r D e r**~~ **==> picture [125 x 53] intentionally omitted <==** **----- Start of picture text -----**<br> No. of clips RoHS Compliant<br>M V - 1 0 2 - 5 5 E<br>Series Finish Length<br>A = black anodized (mm)<br>V = degreased<br>**----- End of picture text -----**<br> ## **Standard Part Numbers** ||**Part Number Description**<br>MV-102-55E†55mm No finish (degreased)|**Packaging**<br>Bulk| |---|---|---| ||MA-102-55E 55mm Black anodized<br>MV-101-27E†27mm No finish (degreased)|Bulk<br>Bulk| ||MA-101-27E†27mm Black anodized|Bulk| ||MV-302-55E 55mm No finish (degreased)|Bulk| ||MA-302-55E 55mm Black anodized|Bulk| ||MV-301-27E 27mm No finish (degreased)|Bulk| ||MA-301-27E 27mm Black anodized|Bulk| †Discontinued **==> picture [146 x 41] intentionally omitted <==** rev 10/21-1 1-866-9-OHMITE • Int’l 1-847-258-0300 • Fax 1-847-574-7522 • www.ohmite.com • info@ohmite.com **177**
Updated at April 29, 2026
With nearly a century of engineering expertise, Ohmite is a premier manufacturer of high-performance resistive and thermal management products. Founded in 1925, the company has continuously evolved alongside the electronics industry, building a reputation for resolving complex design challenges. Ohmite specializes in delivering reliable solutions for high-current, high-voltage, and high-energy applications across the industrial, medical, aerospace, and transportation sectors. The core of our Ohmite offering centers on their advanced cooling and thermal management solutions, particularly natural convection heat sinks. Engineered to efficiently dissipate thermal energy in demanding environments, these heat sinks help designers overcome critical thermal bottlenecks. By effectively managing heat dissipation, Ohmite's thermal products ensure the optimal performance and extended longevity of sensitive electronic assemblies. Complementing their thermal management expertise, our selection includes precision sensing and circuit protection components. Ohmite's robust force sensors and load cells provide dependable measurement capabilities for specialized industrial applications, while their temperature sensing and compensation NTC thermistors offer accurate environmental monitoring. These product lines reflect Ohmite’s enduring commitment to quality, innovation, and specialized component engineering.
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