BD235 - STMICROELECTRONICS

June 2009 Doc ID 4189 Rev 3 1/9

BD235

BD237

Low voltage NPN power transistors

Features

■Low saturation voltage

■NPN transistors

Applications

■Audio, power linear and switching applications

Description

The devices are manufactured in Planar

technology with “Base Island” layout. The

resulting transistor shows exceptional high gain

performance coupled with very low saturation

voltage. The PNP type is BD238.

Figure 1. Internal schematic diagram

SOT-32

321

(TO-126)

Table 1. Device summary

Order codes Marking Package Packaging

BD235 BD235 SOT-32 Tube

BD237 BD237 SOT-32 Tube

www.st.com

Absolute maximum ratings BD235, BD237

2/9 Doc ID 4189 Rev 3

1 Absolute maximum ratings

Table 2. Absolute maximum ratings

Symbol Parameter

Value

Unit

BD235 BD237

VCBO Collector-base voltage (IE = 0) 60 100 V

VCER Collector-emitter voltage (RBE = 1 kΩ) 60 100 V

VCEO Collector-emitter voltage (IB = 0) 60 80 V

VEBO Emitter-base voltage (IC = 0) 5 V

ICCollector current 2 A

ICM Collector peak current (tp < ms) 6 A

PTOT Total dissipation at Tcase = 25°C 25 W

Tstg Storage temperature -65 to 150 °C

TJMax. operating junction temperature 150 °C

BD235, BD237 Electrical characteristics

Doc ID 4189 Rev 3 3/9

2 Electrical characteristics

(Tcase = 25°C; unless otherwise specified)

2.1 Electrical characteristic (curves)

Table 3. Electrical characteristics

Symbol Parameter Test conditions Min. Typ. Max. Unit

ICBO

Collector cut-off current

(IE = 0)

VCB = rated VCBO

VCB = rated VCBO TC= 150°C -0.1

IEBO

Emitter cut-off current

(IC = 0) VEB = 5V -1mA

VCEO(sus)(1)

1. Pulsed duration = 300 µs, duty cycle = 1.5 %.

Collector-emitter

sustaining voltage

(IB = 0)

IC = 100mA

for BD235

for BD237

-V

VCE(sat)(1) Collector-emitter

saturation voltage IC = 1A __ IB = 0.1A -0.6V

VBE(on)(1) Base-emitter on voltage IC = 1A ___ VCE = 2V -1.3V

hFE(1) DC current gain IC = 150mA _ VCE = 2V

IC = 1A_ VCE = 2V

25 -

Figure 2. Safe operating area Figure 3. Derating curves

Electrical characteristics BD235, BD237

4/9 Doc ID 4189 Rev 3

Figure 4. DC current gain (VCE = 2 V) Figure 5. DC current gain (VCE = 4 V)

Figure 6. Collector-emitter saturation

voltage

Figure 7. Base-emitter saturation

voltage

Figure 8. Base-emitter on voltage

Figure 9. Resistive load switching time

(on)

BD235, BD237 Electrical characteristics

Doc ID 4189 Rev 3 5/9

2.2 Test circuit

Figure 11. Resistive load switching test circuit

1. Fast electronic switch

2. Non-inductive resistor

Figure 10. Resistive load switching time

(off)

Package mechanical data BD235, BD237

6/9 Doc ID 4189 Rev 3

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.

BD235, BD237 Package mechanical data

Doc ID 4189 Rev 3 7/9

Revision history BD235, BD237

8/9 Doc ID 4189 Rev 3

4 Revision history

Table 4. Document revision history

Date Revision Changes

11-Feb-2003 1 Initial release.

09-Jul-2007 2 Added: figures 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 and 12.

03-Jun-2009 3 Minor text changes.

BD235, BD237

Doc ID 4189 Rev 3 9/9

Please Read Carefully:

Information in this document is provided solely in connection with ST products. STMicroelectronics NV and its subsidiaries (“ST”) reserve the

right to make changes, corrections, modifications or improvements, to this document, and the products and services described herein at any

time, without notice.

All ST products are sold pursuant to ST’s terms and conditions of sale.

Purchasers are solely responsible for the choice, selection and use of the ST products and services described herein, and ST assumes no

liability whatsoever relating to the choice, selection or use of the ST products and services described herein.

No license, express or implied, by estoppel or otherwise, to any intellectual property rights is granted under this document. If any part of this

document refers to any third party products or services it shall not be deemed a license grant by ST for the use of such third party products

or services, or any intellectual property contained therein or considered as a warranty covering the use in any manner whatsoever of such

third party products or services or any intellectual property contained therein.

UNLESS OTHERWISE SET FORTH IN ST’S TERMS AND CONDITIONS OF SALE ST DISCLAIMS ANY EXPRESS OR IMPLIED

WARRANTY WITH RESPECT TO THE USE AND/OR SALE OF ST PRODUCTS INCLUDING WITHOUT LIMITATION IMPLIED

WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE (AND THEIR EQUIVALENTS UNDER THE LAWS

OF ANY JURISDICTION), OR INFRINGEMENT OF ANY PATENT, COPYRIGHT OR OTHER INTELLECTUAL PROPERTY RIGHT.

UNLESS EXPRESSLY APPROVED IN WRITING BY AN AUTHORIZED ST REPRESENTATIVE, ST PRODUCTS ARE NOT

RECOMMENDED, AUTHORIZED OR WARRANTED FOR USE IN MILITARY, AIR CRAFT, SPACE, LIFE SAVING, OR LIFE SUSTAINING

APPLICATIONS, NOR IN PRODUCTS OR SYSTEMS WHERE FAILURE OR MALFUNCTION MAY RESULT IN PERSONAL INJURY,

DEATH, OR SEVERE PROPERTY OR ENVIRONMENTAL DAMAGE. ST PRODUCTS WHICH ARE NOT SPECIFIED AS "AUTOMOTIVE

GRADE" MAY ONLY BE USED IN AUTOMOTIVE APPLICATIONS AT USER’S OWN RISK.

Resale of ST products with provisions different from the statements and/or technical features set forth in this document shall immediately void

any warranty granted by ST for the ST product or service described herein and shall not create or extend in any manner whatsoever, any

liability of ST.

ST and the ST logo are trademarks or registered trademarks of ST in various countries.

Information in this document supersedes and replaces all information previously supplied.

The ST logo is a registered trademark of STMicroelectronics. All other names are the property of their respective owners.

STMicroelectronics group of companies

Australia - Belgium - Brazil - Canada - China - Czech Republic - Finland - France - Germany - Hong Kong - India - Israel - Italy - Japan -

Malaysia - Malta - Morocco - Philippines - Singapore - Spain - Sweden - Switzerland - United Kingdom - United States of America