# Heat Sink, 12.4 °C/W, D34, 25.4 mm, 25.4 mm, 25.4 mm
**URL**: https://novapart.co/products/E3A-T220-25E/heat-sink-124-c-w-d34-254-mm
**SKU**: E3A-T220-25E
**Manufacturer**: OHMITE
**Category**: Cooling & Thermal Management || Heat Sinks || Natural Convection Heat Sinks
**Price**: €1.3400
**Stock**: 10+
## Specifications
| Parameter | Value |
|---|---|
| Svhc | No SVHC (27-Jun-2024) |
| Product Range | 0 |
| Packages Cooled | 0 |
| Heat Sink Material | Aluminium |
| Thermal Resistance | 0 |
| External Width - Metric | 25.4mm |
| External Height - Metric | 25.4mm |
| External Length - Metric | 0 |
| External Width - Imperial | 1" |
| External Diameter - Metric | - |
| External Height - Imperial | 1" |
| External Length - Imperial | 0 |
| External Diameter - Imperial | - |
## Datasheet
📄 [Download PDF](https://novapart.co/datasheet/farnell:4037114/)
## **EX Series Heatsinks For TO-220 and TO-247 devices and bridge rectifiers**
## **F E a t u r E S**
- Vertical through-hole PCB mounting
- E3A-T220-25E has a 8-32 threaded mounting hole for a bridge rectifier in a D34 type square package
- The thickened side fins can be used to secure the heat sink to a side wall or to mount TO-220"s
- • Threaded mounting holes
|**For**
**Ohmite**
**Surface**
**Thermal**
~~**S E r i E S S P E c i F i c at i O N S**~~
~~Se~~|**For**
**Ohmite**
**Surface**
**Thermal**
~~**S E r i E S S P E c i F i c at i O N S**~~
~~Se~~|**For**
**Ohmite**
**Surface**
**Thermal**
~~**S E r i E S S P E c i F i c at i O N S**~~
~~Se~~|**For**
**Ohmite**
**Surface**
**Thermal**
~~**S E r i E S S P E c i F i c at i O N S**~~
~~Se~~|**For**
**Ohmite**
**Surface**
**Thermal**
~~**S E r i E S S P E c i F i c at i O N S**~~
~~Se~~|**For**
**Ohmite**
**Surface**
**Thermal**
~~**S E r i E S S P E c i F i c at i O N S**~~
~~Se~~|
|---|---|---|---|---|---|
|**Heatsink**|**Package**|**Resistor**|**Area**|**Weight**|**Resistance***|
|**Part Number**|**Type **|**Series**|**(in2 /mm2)**|**(oz./g)**|**(°C/W)**|
|E2A-T220-38E|TO-220|TBH,TCH|7.96 / 5129|0.40 / 11.21|14.0|
|E2A-T220-25E|TO-220|TBH,TCH|5.30 / 2419|0.26 / 7.5|16.4|
|E2A-T247-38E|TO-247|TEH100|7.95 / 5129|0.40 / 11.21|14.0|
|E3A-T220-25E|D34||9.4 / 6064|0.60 / 17.0|12.4|
*Natural convection at 5W dissipation
## ~~**c H a r a c t E r i S t i c S**~~
**Heat sink** Aluminum 6063-T5 or equivalent with either black anodized or degreased finish
**Solder feet** steel tin plated **Interface** for improvement, use thermal **thermal** joint compound or 0.005 **resistance** Grafoil (TGon 800 by Laird) ~~—_— ee~~ **Interface** Sil-Pad 900S by Bergquist or **electrical** equivalent **isolation**
## **Heat Dissipation**
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Air Velocity (ft./min.)
0 100 200 300 400 500 600 700 800 900 1000
100 10
90 9
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50 E2A-T247-38AE 5
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0 0
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Heat Dissipated (watts)
Mounting Surface Temp. Rise C)above Ambient ( ° C/watts) Surface to Ambient ( °
Thermal Resistance from Mounting
**----- End of picture text -----**
(continued)
**172** 1-866-9-OHMITE • Int’l 1-847-258-0300 • Fax 1-847-574-7522 • www.ohmite.com • info@ohmite.com
## **EX Series Heatsinks For TO-220 and TO-247 devices and bridge rectifiers**
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d i m E N S i O N S
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**==> picture [502 x 484] intentionally omitted <==**
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in. (mm)
#6-32 tap thru Tin-plated steel pins
0.090"
0.64" (2.3mm)
E2A-T220-38E (16.3mm) 0.40" 0.160" REF.
(10.2mm)
0.136" ±.010 0.72"
( 3.45mm ±.25) 0.64" 1.50" (18.3mm) 0.156"
(16.3mm) (38.1mm) (4.0mm )
#6-32 thread thru Tin-plated steel pins
0.090"
(2.3mm)
0.64"
E2A-T220-25E (16.3mm) 0.40" 0.160" REF.
(10.2mm)
0.136" ±.010 0.72"
( 3.45mm ±.25) 0.64" 1.00" (18.3mm) 0.156"
(16.3mm) (25.4mm ) (4.0mm )
#6-32 tap thru
0.090"
(2.3mm)
0.64"
E2A-T247-38E (16.3mm) 0.40"
(10.2mm)
0.320"
0.850"
0.136" ±.010 (21.6mm)
( 3.45mm ±.25) 0.64" 1.500" 0.156"
(16.3mm) (4.0mm)
(38.1mm)
ø0.164" hole
#8-32 UNC-2B thread, thru
1.00"
(25.4mm)
E3A-T220-25E
0.50"
(12.7mm)
0.50"
(12.7mm)
1.00" 1.00"
(25.4mm) (25.4mm)
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## ~~**O r d E r i N g i N F O r m at i O N**~~
**Extrusion type RoHS Compliant E 2 A - T 2 2 0 - 3 8 E Series Finish Package Height** EX A = anodized **type**
**==> picture [146 x 41] intentionally omitted <==**
1-866-9-OHMITE • Int’l 1-847-258-0300 • Fax 1-847-574-7522 • www.ohmite.com • info@ohmite.com
**173**
## Links
- [View this product on Novapart](https://novapart.co/products/E3A-T220-25E/heat-sink-124-c-w-d34-254-mm)
- [Request a quote for this part](https://novapart.co/quote/)
- [Supplier page](https://es.farnell.com/ohmite/e3a-t220-25e/heat-sink-aluminium-25-4x25-4x25/dp/4037114)
---
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