# Fast / Ultrafast Diode, 1.2 kV, 8 A, Single, 1.25 V, 50 ns, 80 A

![Product image](https://novapart.co/image/farnell:1295303/)

**URL**: https://novapart.co/products/STTH812DI/fast-ultrafast-diode-12-kv-8-a-single-125-v-50-ns
**SKU**: STTH812DI
**Manufacturer**: STMICROELECTRONICS
**Category**: Semiconductors - Discretes || Diodes & Rectifiers || Fast & Ultrafast Recovery Rectifier Diodes
**Price**: €0.6170
**Stock**: 1000+
**Lead Time**: 120 days (indicative)

## Description

Repetitive Reverse Voltage Vrrm Max:1.2kV; Forward Current If(AV):8A; Diode Configuration:Single; Forward Voltage VF Max:1.25V; Reverse Recovery Time trr Max:50ns; Forward Surge Current Ifsm

## Specifications

| Parameter | Value |
|---|---|
| Svhc | No SVHC (25-Jun-2025) |
| No. Of Pins | 2 Pin |
| Product Range | STTH8 |
| Qualification | - |
| Diode Case Style | TO-220 |
| Diode Configuration | Single |
| Forward Voltage Max | 1.25V |
| Forward Surge Current | 80A |
| Reverse Recovery Time | 50ns |
| Average Forward Current | 8A |
| Operating Temperature Max | 175°C |
| Repetitive Peak Reverse Voltage | 1.2kV |

## Datasheet

📄 [Download PDF](https://novapart.co/datasheet/farnell:1295303/)

**==> picture [61 x 39] intentionally omitted <==**

## **STTH812** 

## Ultrafast recover - 1200 V diode y 

## **Main product characteristics** 

|IF(AV)|8 A|
|---|---|
|VRRM|1200 V|
|Tj|175° C|
|VF(typ)|1.25 V|
|trr(typ)|50 ns|



## **Features and benefits** 

- Ultrafast, soft recovery 

- Very low conduction and switching losses 

- High frequency and/or high pulsed current operation 

- High reverse voltage capability 

- High junction temperature 

- Insulated packages: 

   - TO-220Ins Electrical insulation = 2500 VRMS Capacitance = 7 pF 

   - TO-220FPAC Electrical insulation = 2000 VRMS Capacitance = 12 pF 

## **Description** 

The high quality design of this diode has produced a device with low leakage current, regularly reproducible characteristics and intrinsic ruggedness. These characteristics make it ideal for heavy duty applications that demand long term reliability. 

**==> picture [194 x 237] intentionally omitted <==**

**----- Start of picture text -----**<br>
A K<br>A<br>A<br>K K<br>TO-220AC TO-220FPAC<br>STTH812D STTH812FP<br>K<br>A<br>A<br>NC K<br>D [2] PAK TO-220Ins<br>STTH812G STTH812DI<br>**----- End of picture text -----**<br>


## **Order codes** 

|**Part Number**|**Marking**|
|---|---|
|STTH812D|STTH812D|
|STTH812G|STTH812G|
|STTH812G-TR|STTH812G|
|STTH812FP|STTH812FP|
|STTH812DI|STTH812DI|



Such demanding applications include industrial power supplies, motor control, and similar mission-critical systems that require rectification and freewheeling. These diodes also fit into auxiliary functions such as snubber, bootstrap, and demagnetization applications. 

The improved performance in low leakage current, and therefore thermal runaway guard band, is an immediate competitive advantage for this device. 

1/11 

March 2006 

Rev 1 

11 

_www.st.com_ 

**Characteristics** 

**STTH812** 

## **1 Characteristics** 

## **Table 1. Absolute ratings (limiting values at 25° C, unless otherwise specified)** 

|**Symbol**|**Parameter**|**Parameter**|**Parameter**|**Value**|**Unit**|
|---|---|---|---|---|---|
|VRRM|Repetitive peak reverse voltage|||1200|V|
|IF(RMS)|RMS forward current|TO-220AC / D2PAK / TO-220FPAC||30|A|
|||TO-220AC Ins||20||
|IF(AV)|Average forward current,δ= 0.5|TO-220AC / D2PAK|Tc= 140° C|8|A|
|||TO-220FPAC|Tc= 75° C|||
|||TO-220AC Ins|Tc= 115° C|||
|IFRM|Repetitive peak forward current|tp= 5 µs, F = 5 kHz square||100|A|
|IFSM|Surge non repetitive forward current|tp= 10 ms Sinusoidal||80|A|
|Tstg|Storage temperature range|||-65 to + 175|°C|
|Tj|Maximum operating junction temperature|||175|°C|



## **Table 2. Thermal parameters** 

|**Table 2.**|**Thermalparameters**||||
|---|---|---|---|---|
|**Symbol**|**Parameter**||**Value**|**Unit**|
|Rth(j-c)|Junction to case|TO-220AC / D2PAK|1.9|°C/W|
|||TO-220FPAC|5.4||
|||TO-220AC Ins|3.1||



## **Table 3. Static electrical characteristics** 

|**Symbol**|**Parameter**|**Test conditions**|**Test conditions**|**Min.**|**Typ**|**Max.**|**Unit**|
|---|---|---|---|---|---|---|---|
|IR<br>(1)|Reverse leakage current|Tj= 25° C|VR= VRRM|||8|µA|
|||Tj= 125° C|||5|50||
|VF<br>(2)|Forward voltage drop|Tj= 25° C|IF= 8 A|||2.2|V|
|||Tj= 125° C|||1.30|2.0||
|||Tj= 150° C|||1.25|1.9||



1. Pulse test: tp = 5 ms, δ < 2 % 

2. Pulse test: tp = 380 µs, δ < 2 % 

To evaluate the conduction losses use the following equation: P = 1.5 x IF(AV) + 0.05 IF2(RMS) 

2/11 

**STTH812** 

**Characteristics** 

**Table 4. Dynamic characteristics** 

|**Symbol**<br>**Pa**|**rameter**<br>**Test conditions**|**Min.**|**Typ**|**Max.**|**Unit**|
|---|---|---|---|---|---|
|trr<br>Reverse recov|ery time<br>IF= 1 A, dIF/dt = -50 A/µs,<br>VR= 30 V, Tj= 25° C<br>IF= 1 A, dIF/dt = -100 A/µs,<br>VR= 30 V, Tj= 25° C|||100|ns|
||||50|70||
|IRM<br>Reverse recov|ery current<br>IF= 8 A, dIF/dt = -200 A/µs,<br>VR= 600 V, Tj= 125° C||14|21|A|
|S<br>Softness facto|r<br>IF= 8 A, dIF/dt = -200 A/µs,<br>VR= 600 V, Tj= 125° C||2|||
|tfr<br>Forward recov|ery time<br>IF= 8 A      dIF/dt = 50 A/µs<br>VFR= 1.5 x VFmax, Tj= 25° C|||400|ns|
|VFP<br>Forward recov|ery voltage<br>IF= 8 A, dIF/dt = 50 A/µs,<br>Tj= 25° C||7||V|



## **Figure 1. Conduction losses versus average current** 

## **Figure 2. Forward voltage drop versus forward current** 

**==> picture [462 x 146] intentionally omitted <==**

**----- Start of picture text -----**<br>
P(W) IFM(A)<br>20 80<br>δ = 0.1 δ = 0.2<br>18 δ = 0.05 δ = 0.5<br>70<br>16 T =150°Cj<br>60 (typical values)<br>14 δ = 1<br>12 50<br>10 40<br>T =25°Cj<br>8 30 (maximum values)<br>6 (maximum values)T =150°Cj<br>T 20<br>4<br>10<br>2 IF(AV)(A) δ [=tp/T] tp VFM(V)<br>0 0<br>0 1 2 3 4 5 6 7 8 9 10 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0<br>**----- End of picture text -----**<br>


## **Figure 3. Relative variation of thermal impedance junction to case versus pulse duration** 

## **Figure 4. Relative variation of thermal impedance junction to case versus pulse duration** 

**==> picture [462 x 146] intentionally omitted <==**

**----- Start of picture text -----**<br>
Zth(j-c)/Rth(j-c) Zth(j-c)/Rth(j-c)<br>1.0 1.0<br>Single pulse Single pulse<br>0.9 TO-220ACD2PAK 0.9 TO-220FPAC<br>0.8 TO-220Ins 0.8<br>0.7 0.7<br>0.6 0.6<br>0.5 0.5<br>0.4 0.4<br>0.3 0.3<br>0.2 0.2<br>0.1 tp(s) 0.1 tp(s)<br>0.0 0.0<br>1.E-03 1.E-02 1.E-01 1.E+00 1.E-03 1.E-02 1.E-01 1.E+00 1.E+01<br>**----- End of picture text -----**<br>


3/11 

**Characteristics** 

**STTH812** 

**Figure 5. Peak reverse recovery current versus dIF/dt (typical values)** 

**Figure 6. Reverse recovery time versus dIF/dt (typical values)** 

**==> picture [462 x 332] intentionally omitted <==**

**----- Start of picture text -----**<br>
IRM(A) trr(ns)<br>35 500<br>30 VT =125°CjR=600V IF=2 x IF(AV) 450 IF=2 x IF(AV) VT =125°CjR=600V<br>400<br>25 IF=IF(AV) 350 IF=IF(AV)<br>20 IF=0.5 x IF(AV) 300 IF=0.5 x IF(AV)<br>250<br>15 200<br>10 150<br>100<br>5<br>dIF/dt(A/µs) 50 dIF/dt(A/µs)<br>0 0<br>0 50 100 150 200 250 300 350 400 450 500 0 50 100 150 200 250 300 350 400 450 500<br>Figure 7. Reverse recovery charges versus  Figure 8. Softness factor versus dIF/dt<br>dIF/dt (typical values) (typical values)<br>Qrr(µC) S factor<br>3.0 4.0<br>VT =125°CjR=600V 3.5 IT =125°CVFjR≤=600V2xIF(AV)<br>2.5<br>IF=2 x IF(AV)<br>3.0<br>2.0<br>IF=IF(AV) 2.5<br>1.5 IF=0.5 x IF(AV) 2.0<br>1.0<br>1.5<br>0.5 1.0<br>dIF/dt(A/µs) dIF/dt(A/µs)<br>0.0 0.5<br>0 50 100 150 200 250 300 350 400 450 500 0 50 100 150 200 250 300 350 400 450 500<br>**----- End of picture text -----**<br>


**Figure 9. Relative variations of dynamic parameters versus junction temperature** 

**Figure 10. Transient peak forward voltage versus dIF/dt (typical values)** 

**==> picture [462 x 147] intentionally omitted <==**

**----- Start of picture text -----**<br>
2.252.00 Reference: T =125°CVIFR=I=600VF(AV)j 4540 VFP IT =125°CFj=IF(AV) (V)<br>1.75<br>S factor 35<br>1.50<br>30<br>1.25<br>25<br>1.00<br>0.75 trr 20<br>IRM 15<br>0.50<br>10<br>0.25 QRR<br>0.00 T (°C)j 5 dIF/dt(A/µs)<br>25 50 75 100 125 0<br>0 100 200 300 400 500<br>**----- End of picture text -----**<br>


4/11 

**STTH812** 

**Characteristics** 

**Figure 11. Forward recovery time versus dIF/dt Figure 12. Junction capacitance versus (typical values) reverse voltage applied (typical values)** 

**==> picture [462 x 147] intentionally omitted <==**

**----- Start of picture text -----**<br>
tfr(ns) C(pF)<br>700 1000<br>VFR=1.5 x VT =125°CIFj =IF(AV)F max. VOSCF=1MHzT =25°C=30mVj RMS<br>600<br>100<br>500<br>400<br>10<br>300<br>dIF/dt(A/µs) VR(V)<br>200 1<br>0 100 200 300 400 500 1 10 100 1000<br>**----- End of picture text -----**<br>


**Figure 13. Thermal resistance junction to ambient versus copper surface under tab (Epoxy printed circuit board FR4, ecu = 35 µm)** 

**==> picture [205 x 141] intentionally omitted <==**

**----- Start of picture text -----**<br>
Rth(j-a)(°C/W)<br>80<br>70<br>60<br>50<br>40<br>30<br>20<br>10<br>SCU(cm²)<br>0<br>0 5 10 15 20 25 30 35 40<br>**----- End of picture text -----**<br>


5/11 

**STTH812** 

**Package mechanical data** 

## **2 Package mechanical data** 

Epoxy meets UL94, V0 

Cooling method: by conduction (C) 

Recommended torque value: 0.55 Nm (TO-220AC) 

Maximum torque value: 0.7 Nm (TO-220AC) 

## **Table 5. T0-220AC dimensions** 

|**L2**|||||||**A**<br>**C**<br>**D**<br>**L7**<br>**E**<br>**M**|**REF.**|**DIMENSIONS**|**DIMENSIONS**|**DIMENSIONS**|**DIMENSIONS**|
|---|---|---|---|---|---|---|---|---|---|---|---|---|
||||||||||**Millimeters**||**Inches**||
||||||||||**Min.**|**Max.**|**Min.**|**Max.**|
|||||||||A|4.40|4.60|0.173|0.181|
||||**H2**|||**L5**<br>**L6**<br>**L9**<br>**L4**|||||||
||||**Ø I**|||||C|1.23|1.32|0.048|0.051|
|||||||||D|2.40|2.72|0.094|0.107|
|||||||**L5**|||||||
|||||||||E|0.49|0.70|0.019|0.027|
||**F1**||||||||||||
|||||||||F|0.61|0.88|0.024|0.034|
||||||||||||||
|||||||||F1|1.14|1.70|0.044|0.066|
|||||||||G|4.95|5.15|0.194|0.202|
|||||||||H2|10.00|10.40|0.393|0.409|
||**F**|||||||L2|16.40 typ.||0.645 typ.||
|||||||||L4|13.00|14.00|0.511|0.551|
|||||||||L5|2.65|2.95|0.104|0.116|
||||||||||||||
|||||||||L6|15.25|15.75|0.600|0.620|
||||**G**||||||||||
|||||||||L7|6.20|6.60|0.244|0.259|
|||||||||L9|3.50|3.93|0.137|0.154|
|||||||||M|2.6 typ.||0.102 typ.||
|||||||||Diam. I|3.75|3.85|0.147|0.151|



6/11 

**STTH812** 

**Package mechanical data** 

**Table 6.** 

**T0-220Ins dimensions** 

|**I**|||||||**C**<br>**b2**<br>**c2**<br>**F**<br>**L**<br>**A**<br>**a1**<br>**a2**<br>**b1**<br>**c1**<br>**M**|**REF**|**DIMENSIONS**|**DIMENSIONS**|**DIMENSIONS**|**DIMENSIONS**|**DIMENSIONS**|**DIMENSIONS**|
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
||||||||||**Millimeters**|||**Inches**|||
||||||||||**Min.**||**Max.**|**Min.**||**Max.**|
|||||||||A|15.20||15.90|0.598||0.625|
|||||||||a1||3.75|||0.147||
||||||**B**||||||||||
||||||**Ø I**||||||||||
|||||||||a2|13.00||14.00|0.511||0.551|
|||||||||B|10.00||10.40|0.393||0.409|
||**4**||||||||||||||
|||||||||b1|0.61||0.88|0.024||0.034|
||||||||||||||||
|||||||||b2|1.23||1.32|0.048||0.051|
|||||||||C|4.40||4.60|0.173||0.181|
||||||||||||||||
||||**l2**|||||c1|0.49||0.70|0.019||0.027|
|||||||||c2|2.40||2.72|0.094||0.107|
|||||||||e|4.80||5.40|0.189||0.212|
||||||||||||||||
||||||**e**|||F|6.20||6.60|0.244||0.259|
||||||||||||||||
|||||||||ØI|3.75||3.85|0.147||0.151|
|||||||||I4|15.80|16.40|16.80|0.622|0.646|0.661|
|||||||||L|2.65||2.95|0.104||0.116|
|||||||||l2|1.14||1.70|0.044||0.066|
|||||||||M||2.60|||0.102||



7/11 

**STTH812** 

**Package mechanical data** 

**Table 7. T0-220FPAC dimensions** 

|**L3**|||||||**L7**<br>**E**|**REF**|**DIMENSIONS**|**DIMENSIONS**|**DIMENSIONS**|**DIMENSIONS**|
|---|---|---|---|---|---|---|---|---|---|---|---|---|
||||||||||**Millimeters**||**Inches**||
||||||||||**Min.**|**Max.**|**Min.**|**Max.**|
|||||**Dia**<br>**L6**<br>**L5**<br>**F1**<br>**F**<br>**D**|**A**<br>**B**||||||||
|||||||||A|4.4|4.6|0.173|0.181|
||||**H**||||||||||
|||||||**B**||B|2.5|2.7|0.098|0.106|
||||||||||||||
|||||||||D|2.5|2.75|0.098|0.108|
||**L4**<br>**L2**||||||||||||
|||||||||E|0.45|0.70|0.018|0.027|
|||||||||F|0.75|1|0.030|0.039|
|||||||||F1|1.15|1.70|0.045|0.067|
|||||||||G|4.95|5.20|0.195|0.205|
|||||||||G1|2.4|2.7|0.094|0.106|
|||||||||H|10|10.4|0.393|0.409|
|||||||||L2|16 Typ.||0.63 Typ.||
|||||||||L3|28.6|30.6|1.126|1.205|
|||||||||L4|9.8|10.6|0.386|0.417|
|||||||||L5|2.9|3.6|0.114|0.142|
|||||||||L6|15.9|16.4|0.626|0.646|
||||||||||||||
|||||||||L7|9.00|9.30|0.354|0.366|
|||||||||Dia.|3.00|3.20|0.118|0.126|



8/11 

**STTH812** 

**Package mechanical data** 

**Table 8. D[2] PAK dimensions** 

|**L**|||||**SS THAN 2mm**<br>**A**<br>**D**<br>**R**<br>**V2**|**REF.**|**DIMENSIONS**|**DIMENSIONS**|**DIMENSIONS**|**DIMENSIONS**|
|---|---|---|---|---|---|---|---|---|---|---|
||||||||**Millimeters**||**Inches**||
||||||||**Min.**|**Max**|**Min.**|**Max.**|
||**L2**|||**C2**<br>**A1**|||||||
|||||||A|4.40|4.60|0.173|0.181|
||||||||||||
||||**E**|||A1|2.49|2.69|0.098|0.106|
|||||||A2|0.03|0.23|0.001|0.009|
||**L3**|||||B|0.70|0.93|0.027|0.037|
|||||||B2|1.14|1.70|0.045|0.067|
|||||||C|0.45|0.60|0.017|0.024|
||||**G**|**B**<br>**B2**<br>*** FLAT ZONE NO LE**<br>**A2**<br>**M**<br>**C**<br>*||C2|1.23|1.36|0.048|0.054|
|||||||D|8.95|9.35|0.352|0.368|
|||||||E|10.00|10.40|0.393|0.409|
|||||||G|4.88|5.28|0.192|0.208|
|||||||L|15.00|15.85|0.590|0.624|
|||||||L2|1.27|1.40|0.050|0.055|
|||||||L3|1.40|1.75|0.055|0.069|
|||||||M|2.40|3.20|0.094|0.126|
|||||||R|0.40 typ.||0.016 typ.||
|||||||V2|0°|8°|0°|8°|



**Figure 14. D[2] PAK footprint (dimensions in mm)** 

**==> picture [211 x 125] intentionally omitted <==**

**----- Start of picture text -----**<br>
16.90<br>10.30 5.08<br>1.30<br>3.70<br>8.90<br>**----- End of picture text -----**<br>


In order to meet environmental requirements, ST offers these devices in ECOPACK® packages. These packages have a Lead-free second level interconnect . The category of second level interconnect is marked on the package and on the inner box label, in compliance with JEDEC Standard JESD97. The maximum ratings related to soldering conditions are also marked on the inner box label. ECOPACK is an ST trademark. ECOPACK specifications are available at: www.st.com. 

9/11 

**Ordering information** 

**STTH812** 

## **3 Ordering information** 

|**Part Number**|**Marking**|**Package**|**Weight**|**Base qty**|**Delivery mode**|
|---|---|---|---|---|---|
|STTH812D|STTH812D|TO-220AC|1.86 g|50|Tube|
|STTH812DI|STTH812DI|TO-220Ins|1.86 g|50|Tube|
|STTH812FP|STTH812FP|TO-220FPAC|2.2 g|50|Tube|
|STTH812G|STTH812G|D2PAK|1.48 g|50|Tube|
|STTH812G-TR|STTH812G|D2PAK|1.48 g|1000|Tape & reel|



## **4 Revision history** 

|**Date**|**Revision**|**Description of Changes**|
|---|---|---|
|02-Mar-2006|1|First issue.|



10/11 

**STTH812** 

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11/11 



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