# Bipolar (BJT) Single Transistor, NPN, 500 V, 500 mA, 500 mW, SOT-23, Surface Mount

![Product image](https://novapart.co/image/farnell:4320000/)

**URL**: https://novapart.co/products/STR1550/bipolar-bjt-single-transistor-npn-500-v-ma-mw-sot
**SKU**: STR1550
**Manufacturer**: STMICROELECTRONICS
**Price**: €0.0950
**Stock**: 10+
**Lead Time**: 113 days (indicative)

## Specifications

| Parameter | Value |
|---|---|
| Svhc | No SVHC (25-Jun-2025) |
| No. Of Pins | 3Pins |
| Product Range | - |
| Qualification | - |
| Power Dissipation | 500mW |
| Transistor Mounting | Surface Mount |
| Transistor Polarity | NPN |
| Transition Frequency | - |
| Transistor Case Style | SOT-23 |
| Dc Current Gain Hfe Min | 10hFE |
| Operating Temperature Max | 150°C |
| Continuous Collector Current | 500mA |
| Collector Emitter Voltage Max | 500V |

## Datasheet

📄 [Download PDF](https://novapart.co/datasheet/farnell:4320000/)

## **STR1550** 

## High voltage fast-switching NPN power transistor 

**Datasheet** - **production data** 

## **Features** 

- Excellent hFE linearity up to 50 mA 

**==> picture [48 x 59] intentionally omitted <==**

**----- Start of picture text -----**<br>
3<br>2<br>1<br>SOT-23<br>**----- End of picture text -----**<br>


- Miniature SOT-23 plastic package for surface mounting circuits 

- Tape and reel packaging 

- The PNP complementary type is STR2550 

## **Applications** 

- LED driving 

## **Description** 

## **Figure 1. Internal schematic diagram** 

This device is a high voltage fast-switching NPN power transistor, manufactured using diffused collector planar technology for high switching speeds. 

It employs a base island structure with planar edge termination to enhance switching speeds, while maintaining a wide RBSOA. 

**Table 1. Device summary** 

**Order code Marking Package Packing** STR1550 1550 SOT-23 Tape and reel ~~—p~~ 

_www.st.com_ 

May 2014 

DocID022364 Rev 5 

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This is information on a product in full production. 

**Contents** 

**STR1550** 

|**Contents**|**Contents**|
|---|---|
|**1**|**Electrical ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3**|
|**2**|**Electrical characteristics  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4**|
||2.1<br>Electrical characteristics (curves)     . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5|
|**3**|**Package mechanical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7**|
|**4**|**Revision history  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10**|



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**STR1550** 

**Electrical ratings** 

## **1 Electrical ratings** 

**Table 2. Absolute maximum ratings** 

|**Symbol**|**Parameter**|**Value**|**Unit**|
|---|---|---|---|
|VCBO|Collector-base voltage (IE= 0)|500|V|
|VCEO|Collector-emitter voltage (IB= 0)|500|V|
|VEBO|Emitter-base voltage (IC= 0)|9|V|
|IC|Collector current|0.5|A|
|ICM|Collector peak current (tP< 5 ms)|1|A|
|PTOT|Total dissipation at Tamb= 25 °C|500|mW|
|TSTG|Storage temperature|-65 to 150|°C|
|TJ|Max. operating junction temperature|150|°C|



**Table 3. Thermal data Symbol Parameter Value Unit** RthJA(1) Thermal resistance junction-ambient max 250 °C/W ~~er~~ 

1. Device mounted on PCB area of 1 cm². 

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**STR1550** 

**Electrical characteristics** 

## **2 Electrical characteristics** 

Tcase = 25 °C unless otherwise specified. 

**Table 4. Electrical characteristics** 

|**Symbol**|**Parameter**|**Test conditions**|**Min.**|**Typ.**|**Max.**|**Unit**|
|---|---|---|---|---|---|---|
|ICBO|Collector cut-off current<br>(IE= 0)|VCB= 500 V|||10|µA|
|V(BR)CBO|Collector-base<br>breakdown voltage<br>(IE= 0)|IC= 100 µA|500|||V|
|V(BR)CEO<br>(1)|Collector-emitter<br>breakdown voltage<br>(IB= 0)|IC= 1 mA|500|||V|
|V(BR)EBO|Emitter-base breakdown<br>voltage (IC= 0)|IE= 100 µA|12|||V|
|VCE(sat)<br>(1)|Collector-emitter<br>saturation voltage|IC= 20 mA, IB= 2 mA|||0.2|V|
|||IC= 50 mA, IB= 6 mA|||0.3|V|
|VBE(sat)<br>(1)|Base-emitter saturation<br>voltage|IC= 50 mA, IB= 5 mA|||0.9|V|
|VBE(on)|Base-emitter on voltage|IC= 50 mA, VCE= 10 V|||0.9|V|
|hFE<br>(1)|DC current gain|IC= 1 mA, VCE= 10 V|100||||
|||IC= 50 mA, VCE= 10 V|100||300||
|||IC= 100 mA, VCE= 10 V|10||||



1. Pulse test: pulse duration ≤ 300 µs, duty cycle ≤ 2% 

## **2.1 Electrical characteristics (curves)** 

**==> picture [427 x 186] intentionally omitted <==**

**----- Start of picture text -----**<br>
Figure 2. hFE vs. IC @ VCE= 5 V Figure 3. hFE vs. IC @ VCE= 10 V<br>AM17433v1 AM17434v1<br>hFE hFE<br>EEE eet et<br>A Con oh eo<br>100 100<br>-55°C -55°C<br>NR ee<br>25°C 25°C<br>PC INN S FSCO<br>10 PTI | TTING TTT 10 N N<br>100°C<br>Sasi emesis 100°C ail Se aeaashl tena a<br>Sco ot ANT N T<br>1 A ll 1 a A ll<br>0.001 0.01 0.1 IC(A) 0.001 0.01 0.1 IC(A)<br>**----- End of picture text -----**<br>


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**STR1550** 

**Electrical characteristics** 

## **Figure 4. VCE(sat) vs. IC @ hFE= 5** 

**==> picture [207 x 169] intentionally omitted <==**

**----- Start of picture text -----**<br>
AM17434v1<br>VCE(sat)(V) Tn non<br>A<br>0.8<br>0.7 -55°C<br>CTATT TT<br>0.50.6 C e<br>Co Co<br>0.30.4 CO<br>25°C<br>0.2<br>CT IZA<br>0.1 100°C<br>0 STTL tttll<br>0.001 0.01 0.1 IC(A)<br>**----- End of picture text -----**<br>


**Figure 6. VBE(sat) vs. IC @ hFE= 5** 

**==> picture [206 x 169] intentionally omitted <==**

**----- Start of picture text -----**<br>
AM17437v1<br>VBE(sat)<br>(V) -55°C<br>1.0 C n e a 25°C<br>EE AT<br>0.9<br>0.8 ED 2a<br>g H<br>0.7 100°C<br>0.6 satePeet erm cagll<br>0.5 eT COT<br>eT Cn TT<br>0.4<br>Con<br>0.30.2 Con<br>0.001 0.01 0.1 IC(A)<br>**----- End of picture text -----**<br>


## **Figure 5. VCE(sat) vs. IC @ hFE= 10** 

**==> picture [33 x 6] intentionally omitted <==**

**----- Start of picture text -----**<br>
AM17436v1<br>**----- End of picture text -----**<br>


**==> picture [179 x 164] intentionally omitted <==**

**----- Start of picture text -----**<br>
VCE(sat)(V) Ton ono<br>0.8 A<br>-55°C<br>0.7<br>| Cononmeen<br>0.60.5 FC no<br>25°C<br>|<br>0.4 E R<br>0.3<br>0.2<br>R E<br>0.1 100°C<br>0 aSM ne<br>0.001 0.01 lL 0.1 Tl IC(A)<br>**----- End of picture text -----**<br>


**==> picture [206 x 186] intentionally omitted <==**

**----- Start of picture text -----**<br>
Figure 7. VBE(sat) vs. IC @ hFE= 10<br>AM17437v1<br>VBE(sat)<br>(V) -55°C<br>1.0 m ar an 25°C<br>Oe AT<br>0.9<br>0.8 ON zal<br>SNDcagA<br>0.7 100°C<br>0.6 Seer eel T<br>0.5 T e<br>TTCOT<br>0.4<br>SECn<br>0.30.2 Con<br>0.001 0.01 0.1 IC(A)<br>**----- End of picture text -----**<br>


## **Figure 8. VBE(on) vs. IC @ VCE= 10 V** 

**==> picture [204 x 168] intentionally omitted <==**

**----- Start of picture text -----**<br>
AM17439v1<br>VBE(on)<br>(V)<br>-55°C<br>1.0<br>0.8<br>100°C<br>25°C<br>0.6<br>0.4<br>0.2<br>0.001 0.01 0.1 IC(A)<br>**----- End of picture text -----**<br>


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**STR1550** 

**Package mechanical data** 

## **3 Package mechanical data** 

In order to meet environmental requirements, ST offers these devices in different grades of ECOPACK[®] packages, depending on their level of environmental compliance. ECOPACK[®] specifications, grade definitions and product status are available at: _www.st.com_ . ECOPACK[®] is an ST trademark. 

## **Figure 9. SOT-23 drawings** 

**==> picture [30 x 6] intentionally omitted <==**

**----- Start of picture text -----**<br>
0053390_I<br>**----- End of picture text -----**<br>


6/9 DocID022364 Rev 5 ~~S77~~ 

**STR1550** 

**Package mechanical data** 

**Table 5. SOT-23 mechanical data** 

|||||||||||||**mm**|||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|**Dim.**|||||||||||||||||
||||**Min.**|||||||||**Typ.**||||**Max.**|
|A|||0.89|||||||||||||1.40|
|A1|||0|||||||||||||0.10|
|B|||0.30|||||||||||||0.51|
|C|||0.085|||||||||||||0.18|
|D|||2.75|||||||||||||3.04|
|e|||0.85|||||||||||||1.05|
|e1|||1.70|||||||||||||2.10|
|E|||1.20|||||||||||||1.75|
|H|||2.10|||||||||||||3.00|
|L||||||||||||0.60|||||
|S|||0.35|||||||||||||0.65|
|L1|||0.25|||||||||||||0.55|
|a|||0°|||||||||||||8°|
|||**Figure 10. SOT-23 recommended foot**|||**ure 10. SOT-23 recommended footprint(a)**||||||||||||
||2.89<br>0.95<br>0.48<br>0.97<br>0.99<br>~~a~~<br>i~~.~~<br>~~..~~<br>P~~y~~<br>__<br>ft|||||||||||||||SOT-23 footp_I|



a. Dimensions are in mm. 

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**STR1550** 

**Revision history** 

## **4 Revision history** 

## **Table 6. Document revision history** 

|**Date**|**Revision**|**Changes**|
|---|---|---|
|17-Oct-2011|1|Initial release|
|05-Jun-2012|2|Modified: features,_Table 4_(VCE(sat)values, hFEtest conditions and<br>values)|
|21-May-2013|3|– Modified:_Table 4_(VBE(sat)values, hFEmax. value and V(BR)EBO<br>min. value<br>– Inserted: VBE(on)<br>– Modified:_Table 4_(hFEmax. value)<br>– Added new section:_Electrical characteristics (curves)_|
|27-May-2013|4|– Document status promoted from preliminary to production data|
|09-May-2014|5|– Updated_Table 1: Device summary_and_Section 3: Package_<br>_mechanical data_|



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